Arriel_1 12-00 En

ARRIEL 1

Training manual December 2000 Ref.: X 292 87 960 2

TURBOSHAFT ENGINE

ARRIEL 1

Training Manual

FOREWORD This document provides, in a teaching form, all the information required for the operation and the maintenance of the ARRIEL 1 Turboshaft engine for training purposes only. It will not be updated, and if required, modifications will be included in a new issue.

TURBOMECA Training Centre This document is the property of TURBOMECA and it may not be copied without the express authority of TURBOMECA. For training purposes only © Copyright - TURBOMECA - 2000

0.1 Edition : December 2000

FOREWORD

Training Manual

ARRIEL 1

SUMMARY 0 - Foreword

9 - Starting

1 - Introduction

10 - Electrical system

2 - Power plant

11 - Engine installation

3 - Engine 4 - Oil system

12 - Operating limitations and procedures

5 - Air system

13 - Various aspects of maintenance

6 - Fuel system

14 - Maintenance procedures

7 - Control system

15 - Fault analysis and trouble shooting

8 - Control and indication For training purposes only © Copyright - TURBOMECA - 2000

16 - Checking of knowledge 0.2 Edition : December 2000

SUMMARY

ARRIEL 1

Training Manual

TABLE OF CONTENTS 3 - ENGINE

0 - FOREWORD -

Summary ............................................ Table of contents ................................ List of abbreviations .......................... Conversion table ................................

0.2 0.3 0.7 0.10

1 - INTRODUCTION -

General information ........................... Training method ................................. Training aids ...................................... Training programme .........................

1.2 1.4 1.6 1.8 to 1.12

2 - POWER PLANT -

General presentation ......................... General description ........................... General operation .............................. Principle of adaptation to helicopter .. Main characteristics ........................... Design and development ...................

For training purposes only © Copyright - TURBOMECA - 2000

2.2 2.4 2.8 2.12 2.14 2.22 to 2.27

- Engine ................................................ - Axial compressor ............................... - Gas generator HP section ................... • Centrifugal compressor ................... • Combustion chamber....................... • Gas generator turbine ...................... - Power turbine ..................................... - Exhaust pipe ....................................... - Reduction gearbox ............................. - Transmission shaft and accessory gearbox ....................... • Transmission shaft - twin-engine version ............................................. • Transmission shaft - single engine version ............................................. • Accessory box .................................

3.2 3.8 3.14 3.16 3.22 3.28 3.34 3.40 3.42 3.48 3.50 3.52 3.54 to 3.61

4 - OIL SYSTEM - Oil system ......................................... 4.2 - Lubrication ........................................ 4.8


TABLE OF CONTENTS

Training Manual

ARRIEL 1

TABLE OF CONTENTS (CONTINUED) 6 - FUEL SYSTEM

4 - OIL SYSTEM (CONTINUED) -

Oil tank ............................................. Oil pumps ........................................... Electrical magnetic plugs ................... Oil filter.............................................. Filter pre-blockage indicator .............. Oil cooler ........................................... Centrifugal breather ........................... Magnetic plugs ................................... Strainers ............................................. Indicating devices .............................. Oil pipes and ducts .............................

4.12 4.14 4.20 4.24 4.30 4.34 4.36 4.40 4.42 4.44 4.50 to 4.51

5 - AIR SYSTEM -

Air system ......................................... Internal air system ............................. Air tappings........................................ Compressor bleed valve ..................... Air tapping unions ............................. Air pipes .............................................


5.2 5.4 5.8 5.10 5.18 5.20 to 5.21

- Fuel system ....................................... - Fuel Control Unit ............................... • Fuel pump ........................................ • Fuel filter ......................................... • Manual control ................................ • Metering unit ................................... - Overspeed and drain valve ................ - Start injector electro-valve ................. - Main injection system ........................ - Start injectors ..................................... - Combustion chamber drain valve ...... - Fuel pipes ...........................................

6.2 6.12 6.14 6.18 6.24 6.28 6.30 6.36 6.42 6.46 6.50 6.54 to 6.55

7 - CONTROL SYSTEM - Control system ................................... • General ............................................ • Description ...................................... • Operation .........................................

7.2 7.2 7.4 7.6 to 7.33


TABLE OF CONTENTS

ARRIEL 1

Training Manual

TABLE OF CONTENTS (CONTINUED) 8 - CONTROL AND INDICATION -

Manual control system ....................... Indicating system ............................... Speed indication ................................. Tachometer transmitters ..................... Speed probes (1E, 1K, 1S versions) .. Gas temperature indication ................ Thermocouple probes ........................ Thermocouple junction box (1S version) ........................................ Torque indication ............................... Torquemeter ....................................... Torque transmitter .............................. Miscellaneous indications ..................

10 - ELECTRICAL SYSTEM 8.2 8.6 8.8 8.10 8.14 8.16 8.18

- Electrical system ................................ - Electrical accessories ......................... - Power turbine overspeed safety system ................................................ - Power turbine overspeed sensor ........ - Tachometer box .................................. - Super contingency power system ...... - Electrical harnesses ............................

8.20 8.22 8.24 8.26 8.28 to 8.35

9 - STARTING -

Starting system ................................... Starter ................................................. Ignition system ................................... Ignition units ...................................... Igniter plugs ....................................... Ignition cables ....................................


9.2 9.10 9.16 9.18 9.22 9.26 to 9.27

10.2 10.4 10.6 10.10 10.14 10.24 10.28 to 10.29

11 - ENGINE INSTALLATION -

Engine compartment .......................... Engine mounting ................................ Power drive ........................................ Air intake ........................................... Exhaust system .................................. Engine system interfaces ................... • Oil system ........................................ • Aircraft LP fuel system ................... • Manual controls ............................... • Air system ....................................... - Drain system ...................................... - Fire protection ....................................

11.2 11.4 11.8 11.10 11.12 11.14 11.14 11.16 11.18 11.20 11.22 11.24 to 11.25


TABLE OF CONTENTS

ARRIEL 1

Training Manual

TABLE OF CONTENTS (CONTINUED) - Deep maintenance .............................. 14.62 - Repair and overhaul ........................... 14.64 to 14.65

12 - OPERATING LIMITATIONS AND PROCEDURES - Operating limitations ......................... 12.2 - Operating procedures ........................ 12.6 to 12.9

13 - VARIOUS ASPECTS OF MAINTENANCE -

Maintenance concept ......................... TBOs and life limits ........................... Preventive maintenance ..................... "On-condition" monitoring ................ Corrective maintenance ..................... Lubricants - Fuels - Materials ............ Tooling ............................................... Technical publications ....................... Product support ..................................

13.2 13.4 13.6 13.8 13.10 13.12 13.14 13.16 13.22 to 13.23

14 - MAINTENANCE PROCEDURES - General ............................................... 14.2 - Inspection and check procedures ....... 14.4 - Removal and installation procedures . 14.52 For training purposes only © Copyright - TURBOMECA - 2000

15 - FAULT ANALYSIS AND TROUBLE SHOOTING - Fault analysis ..................................... 15.2 - Trouble shooting ................................ 15.32 to 15.47

16 - CHECKING OF KNOWLEDGE -

Introduction ........................................ Questionnaire 1 ................................. Questionnaire 2 ................................. Questionnaire 3 ................................. Questionnaire 4 ..................................

16.2 16.3 16.6 16.12 16.15 to 16.30

OBSERVATIONS ................................... Last page This training manual is established to meet training requirements and takes into consideration, to a certain extent, ATA 104 specifications. This document has 562 pages. It was produced using a desktop publishing system.


TABLE OF CONTENTS

Training Manual

ARRIEL 1

LIST OF ABBREVIATIONS The abbreviations / symbols shown below may be used during training : A/C ............... AC ................. ACMS ........... ACW ............. AEO .............. ATA .............. BITE ............. Tq (C) ........... cc/h ............... FCV .............. CH ................. cSt ................. CW ................ daN ............... dB ................. DC ................. DGAC ........... Ec .................. EGT ..............

Aircraft Alternating Current Automatic Control Monitoring System Anti-clockwise All Engines Operating Air Transport Association Built In Test Equipment Torque Cubic centimetres per hour Frequency/Voltage Converter Hourly Fuel consumption Centistoke Clockwise DecaNewton Decibel Direct Current Direction Générale de l'Aviation Civile Kinetic energy Exhaust Gas Temperature


FAA .............. FCU .............. FMU ............. FOD .............. ft .................... FWD ............. G ................... g .................... HE ................. HP ................. HP ................. HUMS........... Hz ................. ICP ................ ID .................. IFDS ............. ILS ................ ISA ................ ISV ................

Federal Aviation Administration Fuel Control Unit Fuel Metering Unit Foreign Object Damage Feet Forward Mass air flow Gram High Energy Horse Power High Pressure Health and Usage Monitoring System Hertz Intermediate Contingency Power Identification Integrated Flight Display System Integrated Logistic Support International Standard Atmosphere Servo-valve intensity


LIST OF ABBREVIATIONS

Training Manual

ARRIEL 1

LIST OF ABBREVIATIONS (CONTINUED) kHz ............... kPa ................ kW ................ l/h .................. lb ................... lb/HP.hr ........ lb/hr ............... lb/sec. ............ LRU .............. LTT ............... LVDT ........... m ................... mA ................ MAX ............. MCP .............. MCQ ............. MGB ............. MHz .............. MIN .............. mm ................ mP .................

Kilohertz Kilopascal Kilowatt Litre per hour Pound Pounds per Horse Power per hour Pounds per hour Pounds per second Line Replaceable Unit Learning Through Teaching Linear Voltage Differential Transducer Metre Milliampere Maximum Max Continuous Power Multi Choice Questionnaire Main gearbox Mega Hertz Minimum Millimetre Micro-processor


MTBF ........... MTBUR ........ MTCP ........... MTTR ........... mV ................ N ................... N1 ................. N2 ................. NMD ............. NOVRAM .... NR ................. ω ................... O/S ................ OEI ............... P .................... P2 .................. POS ............... PPM .............. PSI ................ PSIA ............. PSID .............

Mean Time Between Failure Mean Time Between Unscheduled Removal Maintenance Test Control Panel Mean Time to Repair Millivolt Rotation speed Gas generator rotation speed Power turbine rotation speed Navigation and Mission Display Non Volatile Random Access Memory Rotor rotation speed Angular Velocity Overspeed One Engine Inoperative Pressure Compressor outlet pressure Position Parts per million Pounds per Square Inch Pounds per Square Inch Absolute Pounds per Square Inch Differential



ARRIEL 1

Training Manual

LIST OF ABBREVIATIONS (CONTINUED) PSIG ............. PT ................. Q ................... RAM ............. ROM ............. RPM .............. RTD .............. SCP ............... SFC ............... Shp ................ SI ................... SRU .............. t ..................... T/O ................ TBO .............. TET ............... TM ................ t° ................... t4 ...................

Pounds per Square Inch Gauge Power Turbine Fuel flow Random Access Memory Read Only Memory Revolutions Per Minute Resistive Temperature Device Super Contingency power Specific Fuel Consumption Shaft horse power International System Shop replaceable unit Time Take-Off Time Between Overhauls Turbine Entry Temperature Turbomeca Temperature Gas temperature


US G ............. VAC .............. VDC .............. W .................. XTL .............. XCP .............. Z .................... Zp .................. °C .................. °F .................. °K .................. ± .................... Ω ................... ∆ .................... ∆P ................. % ................... < .................... > ....................

US Gallon Volt, Alternating Current Volt, Direct Current Power Throttle position signal Collective Pitch Signal Altitude Pressure altitude Degrees Celsius Degrees Fahrenheit Degrees Kelvin Plus or Minus Ohm Difference (delta) Pressure difference Percent Is lower than Is higher than



ARRIEL 1

Training Manual

CONVERSION TABLE UNIT

International System

Length

1 mm 1m

= =

0.039 inch 3.28 ft = 1.09 yard

Volume

1 dm3 = 1 litre

=

0.26 US gallon

Mass

1 kg

=

2.2 lbs

Power

1 kW

=

1.34 HP

Temperature

°C °K

= =

(°F-32). 5/9 [(°F-32)5/9] + 273

Pressure

1 kPa = 0.01 bar

=

0.145 PSI

Flow (air, oil, fuel)

1 kg/s

=

2.2 lbs/sec.

Specific Fuel Consumption

1 g/kW.h

=

0.00164 lb/HP.hr


British or American Systems


CONVERSION TABLE

Training Manual

ARRIEL 1

1 - INTRODUCTION - General information ...................................................... 1.2 - Training method ............................................................ 1.4 - Training aids .................................................................. 1.6 - Training programme .................................................... 1.8 to 1.12



INTRODUCTION

ARRIEL 1

Training Manual

Training Centre

GENERAL INFORMATION

The Training Centre is located in one of the buildings of TURBOMECA's TARNOS factory.

«The power of knowledge» Adequate training is essential for obvious safety reasons, but also to reduce additional maintenance costs incurred by unjustified removals and excessive downtime.

TARNOS ....

5 kms north of the BAYONNE ANGLET - BIARRITZ district - Access by train (BAYONNE station), by plane (BIARRITZ-PARME airport), by road (A63 highway, TARNOS exit).

Address ......

TURBOMECA - 40220 TARNOS FRANCE

Telex ...........

570 042

Telephone ..

(33) 5 59 74 40 07 or 05 59 74 40 07

Fax ..............

(33) 5 59 74 45 15 or 05 59 74 45 15

E-mail .........

[email protected]

"Greater knowledge leads to greater efficiency".

Objectives of training The main objective is the acquisition of the knowledge required for the tasks to be achieved (know and know how). Further information is also communicated to widen the skill and the experience of the trainee.

Training approach - Performance based training according to task analysis, with classroom sessions, student involvement, practical work and troubleshooting techniques - Advanced training aids : training manual, Computer Aided Presentation (or overhead projection), multimedia courseware and demonstration mock-ups - Experienced and formally trained instructors - Courses are taught in English and French and, in special circumstances, in German and Spanish. For training purposes only © Copyright - TURBOMECA - 2000

The training centre is organized in order to answer to training demands (administration, training aids, instructors).

Training sites Training courses are also conducted in subsidiaries, in approved training centres and on site : - by a TURBOMECA qualified instructor, in certain subsidiaries and approved training centres - or by an instructor detached from TURBOMECA France, in our subsidiaries and in the clients' premises.


INTRODUCTION

ARRIEL 1

Training Manual

TRAINING OBJECTIVES OF TRAINING

«The power of knowledge» Adequate training is essential for obvious safety reasons, but also to reduce additional maintenance costs incurred by unjustified removals and excessive downtime.

TRAINING APPROACH

"Greater knowledge leads to greater efficiency".

TRAINING CENTRE, TURBOMECA Tarnos (FRANCE)

FRANCE ATLANTIC OCEAN

TARNOS BAYONNE BORDES

SPAIN

PARIS

TRAINING SITES Training courses are also conducted in subsidiaries, in approved training centres and on site.

GENERAL INFORMATION For training purposes only © Copyright - TURBOMECA - 2000


INTRODUCTION

Training Manual

ARRIEL 1

TRAINING METHOD Knowledge transmission process

Training method

The required knowledge is transmitted in such a manner that the student may use it efficiently in various circumstances.

The training method is a carefully balanced combination of : - Lecture

The training is conducted in accordance with a process which considers :

- Discussions

- A phase of explanation for understanding

- Exercises

- A phase of assimilation leading to the complete acquisition and long-term retention of the knowledge.

- Practical work.

Continuous checking of knowledge helps to ensure the information is assimilated. It is more a method of work than a testing in the traditional sense (refer to chapter 16).



INTRODUCTION

ARRIEL 1

Training Manual

EXPLANATION

ASSIMILATION

1 KNOWLEDGE TRANSMISSION, PHASES :

2

MEDIA

3

4

- Explanation - Assimilation CHECKING OF KNOWLEDGE : - Continuous checking, treated in

1 - LECTURE

chapter 16

2 - EXERCISES 3 - DISCUSSIONS 4 - PRACTICAL WORK

INSTRUCTOR

STUDENT

KNOWLEDGE TRANSMISSION PROCESS

TRAINING METHOD

TRAINING METHOD For training purposes only © Copyright - TURBOMECA - 2000


INTRODUCTION

Training Manual

ARRIEL 1

TRAINING AIDS Training manual

Multimedia courseware

The training manual is the basic source of information.

Interactive courseware is used to transmit information during a course.

It contains, in a teaching form, all required information and explanations, following a layout derived from the ATA 104 standard. Thus each subject is treated following a plan which allows the material to be adapted to different levels of training.

This multimedia system uses text, photos, illustrations, animation and video. Certain courses are available for sale on CD-ROM. This system with quick and easy access can be very efficient for maintaining knowledge levels in the workplace.

Typical plan : - General (function, position, main characteristics, main components) - Description (general and detailed)

However, only a course delivered by a TURBOMECA instructor or TURBOMECA qualified instructor would allow the issue of an engine maintenance authorisation card.

- Operation (phases, synthesis). Other technical publications are also used during a course.

Demonstration mock-ups are also used for component identification and maintenance procedures.

Computer Aided Presentation or overhead projection Computer Aided Presentation or overhead projection is used to display the illustrations contained in the training manual (the instructor's explanations follow the manual).


Demonstration mock-ups

Note : The information contained in the Training Aids must be considered for training purposes only.


INTRODUCTION

Training Manual

ARRIEL 1

TRAINING MANUAL Note : The information contained in the Training Aids must be considered for training purposes only.

MULTIMEDIA COURSEWARE

COMPUTER AIDED PRESENTATION OR OVERHEAD PROJECTION

DEMONSTRATION MOCK-UPS

TRAINING AIDS For training purposes only © Copyright - TURBOMECA - 2000


INTRODUCTION

Training Manual

ARRIEL 1

TRAINING PROGRAMME The course programme follows the manual. However, it should be noted that the "classroom sessions" alternate with periods devoted to demonstrations and practical work.

Examples of programme :

According to the contents, each session is mainly devoted to description and operation.

- Familiarization course

The engine maintenance aspect is mainly covered by the last part of the manual, which also deals with various elements related to maintenance (standard practices, technical publications, logistics and mainly fault analysis and fault finding).

The following pages provide examples of training programme :

- 1st line maintenance (O level) : preventive and corrective maintenance - 2nd line maintenance (I level) : modules, SRU - 3rd line maintenance (H level) : deep maintenance - 4th line maintenance (D level) : repair or overhaul.



INTRODUCTION

Training Manual

ARRIEL 1

FAMILIARIZATION COURSE Objective : At the end of this course, the student will be able to describe the engine, to explain its principle of operation and to identify the main components of the engine and systems. Programme :

- Introduction

FIRST DAY

- General presentation of the engine - Engine description - Engine systems

- Engine systems (continued)

SECOND DAY

- Main aspects of maintenance - Revision - Checking of knowledge



INTRODUCTION

Training Manual

ARRIEL 1

1st LINE MAINTENANCE COURSE (O LEVEL) : PREVENTIVE AND CORRECTIVE MAINTENANCE Objective : At the end of this course, the student will be able to identify the engine components, to describe and to explain the operation of the engine and its systems, to carry out 1st line maintenance procedures and to diagnose operating failures. Programme :

- Introduction - General

FIRST DAY - Engine presentation - Engine description - Oil system

SECOND DAY

- Air system - Fuel system - Control system - Measurement and indicating systems - Starting

THIRD DAY - Electrical system - Engine installation - Operating limitations and procedures - Various aspects of maintenance

FOURTH DAY - Maintenance procedures - Trouble shooting - Visits - Revision

FIFTH DAY - Examination - Miscellaneous questions



INTRODUCTION

Training Manual

ARRIEL 1

2nd LINE MAINTENANCE COURSE (I LEVEL) : MODULES, SRU Objective : At the end of this course, the student will be able to identify the engine components, to carry out all the 2nd line maintenance procedures (mainly the removal/installation of modules and shop replaceable unit). Programme : The programme mainly includes practical work. This programme can be carried out after the 1st line maintenance programme.

- Introduction

FIRST DAY

- Revision (if this course is not conducted directly after the 1st line course) - Removal of modules - Removal of modules

SECOND DAY

- Inspection and check of modules - Installation of modules

THIRD DAY


- Inspection and checks after installation


INTRODUCTION

Training Manual

ARRIEL 1

3rd LINE MAINTENANCE COURSE (H LEVEL) : DEEP MAINTENANCE Objective : At the end of the course, the trainee will be able to carry out the 3rd line maintenance procedures (deep maintenance). Programme :

- Introduction FROM 3 DAYS TO 3 WEEKS

- Definition of procedures - Practical work

4th LINE MAINTENANCE COURSE (D LEVEL) : REPAIR OR OVERHAUL Objective : At the end of the course, the trainee will be able to carry out the specific tasks regarding the engine and related to his skills (eg : control system, assembly, machining procedures...). Programme :

- Introduction SEVERAL WEEKS

- Definition of procedures - Practical work



INTRODUCTION

Training Manual

ARRIEL 1

2 - POWER PLANT - General presentation .................................................... 2.2 - General description ...................................................... 2.4 - General operation ........................................................ 2.8 - Principle of adaptation to helicopter ........................... 2.12 - Main characteristics ..................................................... 2.14 - Design and development .............................................. 2.22 to 2.27



POWER PLANT

Training Manual

ARRIEL 1

GENERAL PRESENTATION Function The power plant provides power by transforming the energy contained in the air and fuel into shaft power.

Main characteristics - Type : free turbine turboshaft engine, front power drive, external power transmission shaft - Concept : modular - Output shaft speed: 6000 RPM (at 100 %) (except the 1S1) - Mass ≈ 126 kg (277 lbs). The mass may vary according to the engine versions.



POWER PLANT

ARRIEL 1

Training Manual

GAS

AIR

POWER FUEL

6000 RPM at 100 % (except 1S1)

POWER PLANT - Free turbine type - Modular - Mass ≈ 126 kg (277 lbs)

GENERAL PRESENTATION For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

ENGINE GENERAL DESCRIPTION This description considers the main functional components of the engine.

Transmission shaft

Gas generator

- External shaft located in a protecting tube which connects the reduction gearbox to the accessory gearbox.

- Single stage axial compressor

Accessory gearbox

- Centrifugal compressor

- Gearbox containing the accessory drive train and the main power drive.

- Annular combustion chamber with centrifugal fuel injection - Two stage axial turbine.

Power turbine - Single stage axial turbine.

Exhaust pipe - Elliptical, axial exhaust pipe.

Reduction gearbox - Reduction gearbox comprising three helical toothed gears.



POWER PLANT

ARRIEL 1

Training Manual

GAS GENERATOR Axial compressor

Centrifugal compressor

POWER TURBINE

Combustion chamber

EXHAUST PIPE

Turbine

ACCESSORY GEARBOX

MAIN POWER DRIVE

TRANSMISSION SHAFT

REDUCTION GEARBOX

ENGINE GENERAL DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

ENGINE SYSTEMS - GENERAL DESCRIPTION This part deals with the systems and functions of the engine.

Engine handling procedure Entirely automatic. Control lever to start, stop and for emergency control.

Oil system The oil system lubricates and cools the engine components.

Engine indicating

Dry sump system, synthetic oil, tank and cooling unit installed on the aircraft. Pressure, temperature and magnetic particles indications.

Rotation speeds. Gas temperature. Engine torque. Oil temperature and pressure. Miscellaneous indications.

Starting Air system Internal system to pressurise and cool engine internal parts. Accessory air supply system (ventilation of start injectors, engine control). Compressor bleed valve. Air supply to the aircraft.

Cranking by an electric starter. Ignition by High Energy. Manual control.

Electrical system Starting system. Indicating system. Overspeed system. Harness with two or three connectors according to version.

Fuel system Fuel supply through a gear type pump. Delivery through a metering unit and a valve. Start injection through 2 simple injectors. Main injection by a centrifugal wheel.

Control system

Engine installation - Interfaces designed for quick removal and installation of engine - Front and rear supports. Lifting rings

Constant power turbine rotation speed. Acceleration control. Miscellaneous protection systems.

- Miscellaneous equipment (air intake, exhaust, firewalls, transmission shaft, air bleeds, drains, fire protection).

Hydro-mechanical control system (with a mechanical back-up manual control) using fuel as hydraulic fluid.



POWER PLANT

ARRIEL 1

Training Manual

AIR SYSTEM

FUEL SYSTEM

OIL SYSTEM

CONTROL SYSTEM

ENGINE INSTALLATION

FWD

ENGINE HANDLING PROCEDURE

ELECTRICAL SYSTEM ENGINE INDICATING STARTING

ENGINE SYSTEMS - GENERAL DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

GENERAL OPERATION This part deals with the basic operation of the engine.

Transmission shaft

Gas generator

- Transmission of the power from the reduction gearbox to the output shaft.

- Compression of the air in the axial and centrifugal compressors - Combustion of the fuel/air mixture in the annular combustion chamber - Gas expansion in the gas generator turbine which drives the compressors and engine accessories.

Accessory gearbox - Power take-off to drive the helicopter main gearbox - Drive of the accessories by the gas generator through a bevel gear, a vertical drive shaft and a gear train.

Power turbine - Expansion of the gas in the single stage turbine which drives the output shaft through the reduction gearbox.

Exhaust - Discharge overboard of the gas.

Reduction gearbox - Drive, at reduced speed, to the transmission shaft.



POWER PLANT

ARRIEL 1

Training Manual

GAS GENERATOR COMPRESSION

COMBUSTION

POWER TURBINE EXPANSION

EXPANSION

GAS EXHAUST

AIR INLET

ACCESSORY GEARBOX ACCESSORY DRIVE

POWER DRIVE

FUEL

TRANSMISSION SHAFT

REDUCTION GEARBOX

FORWARD POWER TRANSMISSION

DRIVE SPEED REDUCTION

GENERAL OPERATION For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

OPERATION - ADAPTATION This part deals with the parameters and the adaptation of the gas generator and power turbine.

Component adaptation For the engine operation, two functional assemblies can be considered :

Power turbine The power turbine operation is defined by the balance between the power received from the gas generator and the torque applied on the shaft, that is the torque C and the rotation speed N2.

Operation

- The gas generator which provides kinetic energy - The power turbine which transforms the kinetic energy into mechanical power on a shaft.

The operation is represented by the diagram which shows the power W, the rotation speeds N1 and N2 and the max torque limit C imposed by the mechanical transmission :

The two assemblies have different rotation speeds.

- The torque C is a function of the N2 rotation speed

Gas generator

- The power W is equal to the torque C multiplied by the angular velocity ω

The gas generator operation is defined by : - The air mass flow G (air flow which enters the engine)

- At constant N2 speed, the power is only a function of the torque

- The air pressure P2 and air temperature t2 at the centrifugal compressor outlet

- The engine parameters can be represented as a function of a reference parameter ; N1 for example.

- The fuel flow Q injected into the combustion chamber - The gas temperature TET at the turbine entry - The rotation speed N1 of the gas generator - The kinetic energy Ec supplied to the turbine.



POWER PLANT

ARRIEL 1

Training Manual GAS GENERATOR

POWER TURBINE C (shaft torque)

N1 (rotation speed) Ec (kinetic energy)

G (air mass flow)

N2 rotation speed (constant) W (shaft power)

P2, t2 (compressor outlet pressure and temperature)

TET (turbine entry temperature) Q (fuel flow) ENGINE PARAMETERS

W

C

e qu

or xt

Isospeeds N1

Ma

W=C.ω ω=2 πN 60

G

0 /P P2 W

CH T TE

SFC

N2 Power W and speeds N1, N2

N2 Torque as a function of N2

N1

P2/P0: Compression ratio CH : Hourly fuel consumption SFC : Specific fuel consumption

COMPONENT ADAPTATION

OPERATION - ADAPTATION For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

PRINCIPLE OF ADAPTATION TO HELICOPTER Power transmission

Installation requirements

The mechanical power supplied by the engine, is used to drive the helicopter rotors through a mechanical transmission.

The main functional requirements of the installation are : - Constant rotor rotation speed NR in all operating conditions

This power drives : - Max torque limit C (usually imposed by the aircraft transmission)

- The main rotor (approximately 82 %) - The tail rotor (approximately 10 %)

- Complete engine protection (N1 and N2 speeds, TET temperature, compressor surge ∆Q/∆t…)

- The main gearbox (approximately 8 %).

- Good load sharing (in the case of a multi-engine configuration).

Twin engine configuration In a twin engine configuration, the engines are installed at the rear of the main gearbox. The power turbines of the two engines are mechanically connected to the main gearbox which drives the rotors (main and tail rotors).


Adaptation to requirements To have a constant rotation speed of the power turbine N2, the power supplied by the engine is automatically adapted to the demand. This adaptation is ensured by the control system which meters the fuel flow injected into the combustion chamber so as to deliver the required power (variation of the gas generator N1 rotation speed) while keeping the engine within its operational limits.


POWER PLANT

ARRIEL 1

Training Manual MAIN ROTOR 82%

MAIN GEARBOX

ENGINE 2

ENGINE 100%

TAIL ROTOR

ENGINE 1 MAIN GEARBOX 8%

TAIL ROTOR 10%

MAIN ROTOR

POWER TRANSMISSION

TWIN ENGINE CONFIGURATION

N2

W - Power

NR (constant) N1, N2, TET,

W

Q/ t N2 N2

time Max torque C

t

INSTALLATION REQUIREMENTS

ADAPTATION TO REQUIREMENTS

PRINCIPLE OF ADAPTATION TO HELICOPTER For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

MAIN CHARACTERISTICS (1) Mass, dimensions and identification Mass (dry) - Engine with specific equipment and without fluid : ≈ 126 kg (277 lbs) it may vary according to the engine version. Dimensions - Engine : • Length : 1166 mm (45.5 inches) • Width : 465.5 mm (18.2 inches) • Height : 609 mm (23.8 inches) Identification - Each module has an identification plate. - The identification plate of the complete engine is located on the module 1 protection tube.



POWER PLANT

ARRIEL 1

Training Manual

609 mm (23.8 inches)

1166 mm (45.5 inches)

POWER PLANT MASS (dry and with specific equipment) ≈ 126 kg (277 lbs)

465,5 mm (18.2 inches)

TURBOMECA

64320 BORDES - FRANCE Brevets SZYDLOWSKI

ARRIEL

Module référence

TURBOMECA

64320 BORDES - FRANCE Brevets SZYDLOWSKI

ARRIEL Date Contrôles Certificat

P

kW

MASS, DIMENSIONS AND IDENTIFICATION

MAIN CHARACTERISTICS (1) For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

MAIN CHARACTERISTICS (2) Operational ratings The operational ratings correspond to given conditions of helicopter operation. The ratings are generally defined under determined speed and temperature conditions.

• Super contingency power (SCP or 1 min) : extreme rating used in place of max. contingency on some versions. Its limited use requires particular maintenance practices.

The following operational ratings are considered : - AEO ratings (All Engines Operating) : • Max take-off power (T/O) : max rating which can be used during take-off. This rating has a limited duration (5 minutes continuous) • Max continuous power (MCP) : rating which can be used without time limitation (this does not imply that it is used permanently) - OEI ratings (One Engine Inoperative) : • Max contingency power (MCP) : rating which can be used in the case of one engine failure during take-off or landing. This rating is usually limited to a period of continuous operation : 2 minutes 30 seconds. • Intermediate contingency power (ICP) : rating which can be used in the case of one engine failure in flight. This rating is usually limited to 30 minutes or unlimited



POWER PLANT

ARRIEL 1

Training Manual

W

A.E.O. RATINGS

O.E.I. RATINGS MAX CONTINGENCY POWER (MCP)

T/O

5 minutes

MAX CONTINUOUS POWER (MCP)

2 minutes 30 seconds

SCP

INTER CONTINGENCY POWER (ICP)

unlimited

1 minute

OPERATIONAL RATINGS



POWER PLANT

Training Manual

ARRIEL 1

MAIN CHARACTERISTICS (3) Factors which affect performance

Evolution of specific fuel consumption (SFC)

The engine performance is affected by flight and atmospheric conditions. The effects of these conditions are usually indicated by graphs which show the evolution of performance as a function of parameters likely to modify it (example : atmospheric temperature t0 and pressure altitude Z).

The specific fuel consumption varies with the operating conditions.

Power evolution (W)

The specific fuel consumption decreases, when the power (W) increases (better thermal efficiency). For this type of installation, the specific fuel consumption which is mostly considered is that at the cruise rating.

The power delivered by the engine decreases when the altitude (Z) and the temperature (t0) increase (this is due to the air mass flow decrease through the engine). The conditions of the engine installation on the aircraft should also be noted (miscellaneous losses due to installation) as well as the flight conditions (essentially the aircraft speed). Evolution of fuel consumption (CH) The fuel consumption decreases at a given rating, when the altitude (Z) and the temperature (t0) increase.



POWER PLANT

ARRIEL 1

Training Manual

W (kW)

CH

Z=

Z=

600 0m

0m

Z=

(0

Z=

(19

680

-

+ 15 °C (59 °F)

0m

ft)

ft)

60 00

m

(0

ft)

(19 68 0f t)

t0

t0

EVOLUTION OF POWER (W)

EVOLUTION OF FUEL CONSUMPTION (CH)

SFC (g/kW.h) A = Cruise condition A

W (kW)

EVOLUTION OF SPECIFIC FUEL CONSUMPTION (SFC)

FACTORS WHICH AFFECT PERFORMANCE



POWER PLANT

Training Manual

ARRIEL 1

MAIN CHARACTERISTICS (4) Engine operating envelope

Limitations

The engine is designed to operate within a given climatic envelope.

The engine operates within various limitations : rotation speeds, temperatures, pressures…

The envelope is defined by :

Refer to corresponding chapters and official publications.

- The atmospheric temperature t0 - The pressure altitude Zp - And lines of standard atmosphere. Flight envelope The flight envelope is illustrated by the t0/Zp diagram and the lines of standard atmosphere, with the max tropical zone and the min arctic zone. Engine starting envelope The starting and relight envelope is defined in the same way, but it is also affected by the specifications of oil and fuel used, and sometimes by particular procedures.



POWER PLANT

ARRIEL 1

Training Manual

ISA - International standard atmosphere

*

Max - Tropical zone t0

Min - Arctic zone

°C

+50°

t0

Depending on oil and fuel specifications. Can also require special operating procedures.

°C

+50°

Max

+15°

Max

ISA Min

-50°

-500 0

ISA

* -50°

Min

Zp

FLIGHT ENVELOPE

Zp

STARTING ENVELOPE

ENGINE OPERATING ENVELOPE



POWER PLANT

Training Manual

ARRIEL 1

DESIGN AND DEVELOPMENT (1) Principles of design

Development steps

The engine is designed to meet the aircraft propulsion requirements and particularly for the new generation of helicopters.

- Certification in 1977 by the French Authorities. - The first production engine was delivered in January 1978.

The engine design is based on : - ARRIEL engines will be in service far beyond 2000. - An optimised thermodynamic cycle which gives high performance - Simple and reliable components giving a good supportability, and a good maintainability to reduce the costs.

Engine development

- Example : ARRIEL 1A2. ARRIEL - According to TURBOMECA tradition : name of a Pyrenean lake. - 1 : Type

The ARRIEL engine is based on research and experience of other engines : - First generation engines : ASTAZOU, ARTOUSTE and TURMO


Engine designation

- A : Variant - 2 : Version.


POWER PLANT

ARRIEL 1

Training Manual

Engine design

Optimised thermodynamic cycle

ARRIEL 1 650 - 700 Shp

Simple and reliable components

Supportability Maintainability

ASTAZOU 500 - 1000 Shp ARTOUSTE 400 - 850 Shp

High performance

Cost reduction

TURMO 1500 - 1600 Shp

ENGINE DEVELOPMENT

PRINCIPLES OF DISIGN In service far beyond 2000

STEPS 1978

ARRIEL lake

First production

1977 Certification

TIME

Example : ARRIEL 1A2 ARRIEL : Name of a Pyrenean lake for the turboshaft engines 1 : Type A : Variant 2 : Version

ENGINE DESIGNATION

DEVELOPMENT STEPS

DESIGN AND DEVELOPMENT (1) For training purposes only © Copyright - TURBOMECA - 2000


POWER PLANT

Training Manual

ARRIEL 1

DESIGN AND DEVELOPMENT (2) Application

Engine fleet status

The ARRIEL 1 is presently destined for the following helicopters : Squirrel and Dolphin (EUROCOPTER), A 109 K2 (Agusta), S 76 (Sikorsky), BK 117 (MBB).

At the beginning of ..., we can note : - Number of ARRIEL 1 engines produced : ................ - Number of ARRIEL 1 engines in operation : ...........

Maintenance concept

- Operating hours : .......................................................

The ARRIEL is designed to provide a high availability rate with reduced maintenance costs. The main aspects of the maintenance concept are the following : - Full modularity - Good accessibility - Reduced removal and installation times - "On condition" monitoring - High initial TBO - Low cost of ownership : • Low production costs • Durability (TBO, defined and proven life limits) • High reliability • Low fuel consumption.



POWER PLANT

ARRIEL 1

Training Manual

PT-HALB

S 76 (SIKORSKY)

SQUIRREL (EUROCOPTER)

CONOCO

G-BKXD SA 365 N

Management Aviation

BK 117 (MBB)

DOLPHIN (EUROCOPTER)

MAINTENANCE CONCEPT REGA I-RAIE

- Actual modularity

A 109 K2 (AGUSTA)

- Good accessibility - Reduced time of removal and installation

FLEET STATUS

- Condition monitoring

- Arriel 1 engines produced

- High initial TBO

- Arriel 1 engines in service

- Low cost of ownership

- Operating hours



POWER PLANT

Training Manual

ARRIEL 1

DESIGN AND DEVELOPMENT (3) ARRIEL family The great diversity of ARRIEL 1 operation is represented in the table below including : - Certification year - Version - Helicopter type - Engine power - Differences



POWER PLANT

ARRIEL 1

Training Manual

ARRIEL 1A

DOLPHIN 365 C

651 shp (2' 30")

ARRIEL 1B

SQUIRREL AS 350 B

640 shp (5')

ARRIEL 1A1

DOLPHIN 365 C1

667 shp (2' 30")

max N1, W and flight envelope increased

ARRIEL 1A2

DOLPHIN 365 C2

670 shp (2' 30")

New centrifugal compressor

1980 ARRIEL 1C

DOLPHIN 365 N DOLPHIN 365 C3

700 shp (2' 30")

Gas generator turbine with fir-tree mounted blades, new combustion chamber, increased N2

1982 ARRIEL 1C1

DOLPHIN 365 N1

723 shp (2' 30")

1983 ARRIEL 1M

DOLPHIN 365 F

777 shp (2' 30")

ARRIEL 1K

AGUSTA A 109 K

723 shp (2' 30")

ARRIEL 1D

SQUIRREL AS 350 B1/L1

683 shp (5')

ARRIEL 1S

SIKORSKY S 76 A

772 shp (2' 30")

1977

1979

1985

1986

ARRIEL 1 MN DOLPHIN 365 F ARRIEL 1 D1 SQUIRREL AS 350 B2/L2 1988 ARRIEL 1 M1 PANTHER 365 K ARRIEL 1 C2 DOLPHIN 365 N2

777 shp (2' 30")

1991 ARRIEL 1E

760 shp (2' 30")

BK 117

Free wheel, long exhaust pipe

Turbine materials, power turbine bearing modified 1 minute rating Adaptation to Agusta aircraft Max fuel flow limit Free wheel, power turbine support and exhaust pipe of the 1B Sealed turbine blades Adaptation to Sikorsky aircraft (support, transmission, systems...).

1S standard. Adaptation to the BK 117

ARRIEL FAMILY



POWER PLANT

Training Manual

ARRIEL 1

3 - ENGINE - Engine ............................................................................. - Axial compressor ........................................................... - Gas generator HP section.............................................. • Centrifugal compressor ............................................................. • Combustion chamber ................................................................. • Gas generator turbine ................................................................ - Power turbine................................................................. - Exhaust pipe................................................................... - Reduction gearbox......................................................... - Transmission shaft and accessory gearbox ................. • Twin-engine transmission shaft................................................. • Single engine transmission shaft ............................................... • Accessory gearbox ......................................................................


3.2 3.8 3.14 3.16 3.22 3.28 3.34 3.40 3.42 3.48 3.50 3.52 3.54 to 3.61 3.1

Edition : December 2000

ENGINE

ARRIEL 1

Training Manual

ENGINE - GENERAL Function

Main components

The engine transforms the energy in the air and fuel into mechanical power on a shaft.

- Gas generator

Main characteristics - Type : Free turbine with forward drive via an external shaft - Power class : from 480 to 560 kW (650 to 760 Shp) according to version - Specific fuel consumption : according to version (see maintenance manual) - Gas generator speed (N1) : approximately 52000 RPM at 100 % • Direction of rotation : anti-clockwise

• Axial compressor (module M02) • HP section (module M03) - Centrifugal compressor - Annular combustion chamber - Two stage turbine - Single stage power turbine (module M04) - Exhaust pipe - Reduction gearbox (module M05) - Transmission shaft and accessory gearbox (module M01).

- Power turbine speed (N2) : 41586 RPM at 100 % • Direction of rotation : clockwise - Output shaft speed : 6000 RPM at 100 % (except the 1S1) • Direction of rotation : clockwise

Note : Direction of rotation given viewed from the rear.



ENGINE

ARRIEL 1

Training Manual

AXIAL COMPRESSOR

CENTRIFUGAL COMPRESSOR

COMBUSTION CHAMBER

TURBINE

POWER TURBINE

EXHAUST PIPE

Type : Free turbine Power class : From 480 to 560 kW (650 to 760 Shp) Specific fuel consumption : According to version Gas generator speed (N1) : Approximately 52000 RPM at 100% (ACW) Power turbine (N2) : 41586 RPM at 100% (CW) Output shaft : 6000 RPM at 100% (CW) except 1S1 TRANSMISSION SHAFT AND ACCESSORY GEARBOX

REDUCTION GEARBOX

ENGINE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

ARRIEL 1

Training Manual

ENGINE - DESCRIPTION Main components

Modular layout

- Gas generator • Axial compressor • Centrifugal compressor • Combustion chamber • Two stage turbine

The engine comprises 5 modules : - Module M01 : Transmission shaft and accessory gearbox - Module M02 : Axial compressor - Module M03 : Gas generator HP section

- Single stage power turbine

- Module M04 : Power turbine

- Exhaust pipe

- Module M05 : Reduction gearbox.

- Reduction gearbox - Transmission shaft

Note : A module is a sub-assembly which can be replaced on-site (2nd line maintenance) without complex tooling or adaptation work.

- Accessory gearbox.

Note : Some accessories are provided with each module.

Each module has an identification plate. The engine identification plate is fitted on the right hand side of the M01 protection tube.

In this manual, those components are dealt with in the chapters corresponding to the main systems.



ENGINE

ARRIEL 1

Training Manual

MODULE M02 AXIAL COMPRESSOR

MODULE M04 POWER TURBINE MODULE M03 GAS GENERATOR HIGH PRESSURE SECTION

MODULE M01 TRANSMISSION SHAFT AND ACCESSORY GEARBOX

MODULE M05 REDUCTION GEARBOX

ENGINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

ARRIEL 1

Training Manual

ENGINE - OPERATION The engine provides power by transforming the energy in the air and fuel into mechanical energy on a shaft. The process comprises compression, combustion, expansion and the transmission of the power.

Expansion - The gas expands in the gas generator turbine which extracts the energy required to drive the compressor and accessories (N1 rotation : 52000 RPM ACW) During this phase the pressure and temperature of the gas drop, whilst the velocity increases.

Compression The ambient air is compressed by an axial supercharging compressor and a centrifugal compressor. This phase is essentially characterised by the air flow (approx. 2.5 kg/s ; 5.5 lbs/sec.) and the compression ratio (approx. 8.2).

Combustion

- There is a further expansion in the power turbine which extracts most of the remaining energy to drive the output shaft (N2 rotation : 41586 RPM CW) After the power turbine the gas is discharged overboard via the exhaust pipe, giving a slight residual thrust.

Power transmission

The compressed air is admitted into the combustion chamber, mixed with the fuel and burnt in a continuous process.

The power is transmitted forward by a reduction gearbox and an external transmission shaft.

The air is divided into two flows : Note : The engine reference stations are :

- A primary flow for combustion - A secondary flow for cooling the gas. This phase is essentially characterised by the temperature rise, flame temperature approx. 2500 °C and turbine entry temperature of approx. 1100 °C, and a pressure drop of about 4 %.


0 1 1' 2 3 4 5

-

Air intake Axial compressor inlet Axial compressor outlet Centrifugal compressor outlet Turbine inlet Gas generator turbine outlet Power turbine outlet.


ENGINE

ARRIEL 1

Training Manual

Primary air Residual thrust ≈ 15 daN (33 lbs)

Gas Secondary air

AIR FLOW 2.5 kg/s (5.5 lbs/s)

EXHAUST

2500 (4532) 0

1

1'

2

3

101,3 P kPa (14.7) (PSI) t °C (°F) V

800 (116)

600 (1080)

POWER TRANSMISSION (power transmitted forward by a reduction gearbox and an external shaft)

300 (43.5)

320 (608) 108 (15.7)

65 (149)

15 (59)

AIR INLET

5

1125 (2057) 880 (1616)

820 (118.9) 160 (23.2)

4

Values given for information at a given reference rating COMPRESSOR

COMBUSTION CHAMBER

COMPRESSION

COMBUSTION

TURBINES EXPANSION

ENGINE - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

ARRIEL 1

Training Manual

AXIAL COMPRESSOR - GENERAL Function

Main components

The axial compressor ensures a first stage of compression to supercharge the centrifugal compressor.

- Rotating components

Position - At the front of the engine (the axial compressor assembly forms the module M02).

• Air inlet cone • Axial wheel, shaft, bearing and accessory drive shaft - Stationary components • Diffuser • Casing.

Main characteristics - Type : axial transonic supercharging compressor - Air flow : 2.5 kg/sec (5.5 lbs/sec.) - Outlet pressure : 160 kPa (23.2 PSI) - Outlet temperature : 65 °C (149 °F)



ENGINE

ARRIEL 1

Training Manual

WHEEL

DIFFUSER

SHAFT

Type : Axial transonic supercharging compressor Air flow : 2.5 kg/s (5.5 lbs/sec.) Outlet pressure : 160 kPa (23.2 PSI) Outlet temperature : 65 °C (149 °F)

AIR INLET CONE

BEARING

CASING

ACCESSORY DRIVE SHAFT

AXIAL COMPRESSOR - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

AXIAL COMPRESSOR - DESCRIPTION The axial compressor module (module M02) includes rotating and stationary components.

Stationary components The stationary assembly includes the diffuser and the casing.

Rotating components The rotating assembly comprises the shaft, the inlet cone, the axial wheel and the accessory drive gear. The inlet cone, made of light alloy, is screwed into the front of the shaft. The compressor wheel is fitted to the shaft. It is a disc made of titanium alloy with blades cut from the solid. The shaft connects the centrifugal compressor to the axial compressor. The shaft is secured by a nut onto the tie-bolt. This assembly is supported by two bearings : a ball bearing at the rear of the axial compressor and a ball bearing in a flexible cage at the front of the centrifugal compressor.

The diffuser (diffuser-straightener) welded inside the casing has two rows of steel stator vanes which form a divergent passage for the air. The casing, made of steel, houses all the compressor components. It has a front flange for the mounting of the air inlet duct and a rear flange for the attachment to the module M03. The inner hub of the casing provides the location for the bearings. The casing has a boss for the mounting of the compressor bleed valve. The module identification plate is located at the front of the casing.

The accessory drive consists of a bevel gear on the shaft which drives a vertical drive shaft.



ENGINE

ARRIEL 1

Training Manual WHEEL

BEARING

DIFFUSER

NUT

TIE-BOLT IDENTIFICATION PLATE

SHAFT

ACCESSORY DRIVE GEAR INLET CONE

CASING CASING DIFFUSER WHEEL SHAFT

INLET CONE

AXIAL COMPRESSOR - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

AXIAL COMPRESSOR - OPERATION The axial compressor ensures a first stage of compression in order to supercharge the centrifugal compressor.

Compressor air flow The ambient air, admitted through the air intake duct and guided by the inlet cone, flows between the blades of the axial compressor. The air is discharged rearwards with an increased axial velocity. The air then flows through the vanes of the diffuser. Due to the divergent passage, the air velocity is reduced and the pressure increased.

Operating parameters In standard conditions, the air flow is 2.5 kg/s (5.5 lbs/ sec.), the outlet pressure 160 kPa (23.2 PSI) and the outlet temperature 65 °C (149 °F). The rotation speed of the axial compressor wheel is obviously the gas generator speed. In order to avoid compressor surge, a valve discharges overboard a certain amount of air in certain operating conditions (refer to "AIR SYSTEM" chapter for further details on the compressor bleed valve).

The flow is straightened by the stator vanes before being admitted, through an annular duct, to the centrifugal compressor.



ENGINE

ARRIEL 1

Training Manual

ACCELERATION OF THE AIR

COMPRESSION AND STRAIGHTENING OF THE AIR

P1' : AIR DISCHARGED THROUGH THE COMPRESSOR BLEED VALVE

ADMISSION OF AMBIENT AIR (2.5 kg/s / 5.5 lbs/sec.)

SUPERCHARGING OF THE CENTRIFUGAL COMPRESSOR (160 kPa / 23.2 PSI ; 6 °C / 149 °F)

AXIAL COMPRESSOR - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

GAS GENERATOR HP SECTION Function

Main components

The HP section of the gas generator ensures the phases of compression (second stage), combustion and expansion (first stage).

- Centrifugal compressor

It provides the energy necessary to drive the power turbine.

- Turbine.

Position - It forms the module M03 and is mounted between the module M02 (axial compressor) and the module M04 (power turbine).

- Combustion chamber

Note : The power turbine nozzle guide vane belongs to the module M03.

Main characteristics - Identification plate on the turbine casing. For further information, refer to following pages.



ENGINE

ARRIEL 1

Training Manual

COMBUSTION CHAMBER

TURBINE

IDENTIFICATION PLATE

CENTRIFUGAL COMPRESSOR

GAS GENERATOR HP SECTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

CENTRIFUGAL COMPRESSOR - GENERAL Function

Main components

The compressor supplies the compressed air required for combustion.

- Rotating components (wheel, shaft, bearing) - Stationary components (diffusers, casings).

Supercharged by the axial compressor, it ensures the second stage of compression.

Position - At the front of the module M03.

Main characteristics - Type : centrifugal, high efficiency - Air flow : 2.5 kg/s (5.5 lbs/sec.) - Compression ratio : 5.4/1 (global : 8.2/1) - Outlet temperature : 320 °C (608 °F)



ENGINE

Training Manual

ARRIEL 1

CASINGS

DIFFUSERS

BEARING

Type : Centrifugal, high efficiency TIE-BOLT

Air flow : 2.5 kg/s (5.5 lbs/sec.) Compression ratio : 5.4 / 1 (global : 8.2 / 1) Outlet temperature : 320 °C (608 °F) CENTRIFUGAL WHEEL

CENTRIFUGAL COMPRESSOR - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

CENTRIFUGAL COMPRESSOR DESCRIPTION The centrifugal compressor assembly includes rotating and stationary components.

Rotating components The main rotating component is the centrifugal wheel. The wheel has blades which are cut from the solid in a disc of titanium alloy and has a labyrinth seal on the rear shaft. The front part of the wheel connects to the axial compressor shaft. The rear part has a curvic-coupling for the mounting of the centrifugal fuel injection wheel. The rotating components are secured by a tie-bolt.


Stationary components The stationary assembly includes the diffusers and the casings. The compressor front cover is mounted inside the external casing by means of a ring of bolts which also secure the axial compressor casing, the front cover and the diffuser assembly. The external casing of the centrifugal compressor is bolted to the turbine casing. It is provided with several bosses for air bleeds. The diffuser assembly comprises the first stage diffuser (radial stator vanes) and the second stage diffuser (axial stator vanes). The diffuser back-plate forms a partition between the compressor and the combustion chamber. The fuel injection system is mounted on its inner hub.


ENGINE

ARRIEL 1

Training Manual

1st STAGE DIFFUSER WHEEL

2nd STAGE DIFFUSER

DIFFUSER ASSEMBLY LABYRINTH SEAL

COMPRESSOR FRONT COVER

BEARING TIE-BOLT

CURVIC COUPLING WHEEL FUEL INJECTION SYSTEM EXTERNAL CASING

EXTERNAL CASING

COMPRESSOR FRONT COVER

CENTRIFUGAL COMPRESSOR - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

CENTRIFUGAL COMPRESSOR OPERATION The centrifugal compressor ensures the main stage of compression.

Compressor air flow The air supplied by the axial compressor flows between the blades of the centrifugal compressor. The air pressure increases due to the divergent passage between the blades and the air velocity increases due to the centrifugal flow.

Operating parameters In standard conditions, the air flow is 2.5 kg/s (5.5 lbs/ sec.), the compression ratio 5.4 (total 8.2), the outlet pressure 820 kPa (118.9 PSI) and the outlet temperature 320 °C (608 °F). The compressor wheel rotation speed is obviously the gas generator speed.

The air leaves the tips of the blades at very high velocity and then flows through the first stage diffuser vanes where the velocity is decreased and the pressure is increased. The air then passes through an elbow and the flow becomes axial. In the second stage diffuser, the velocity is again decreased and the pressure increased. The air is then admitted into the combustion chamber.



ENGINE

ARRIEL 1

Training Manual

COMPRESSION OF THE AIR IN THE DIFFUSERS ACCELERATION AND COMPRESSION OF THE AIR

AIR ADMITTED INTO THE COMBUSTION CHAMBER (820 kPa / 118.9 PSI ; 320 °C / 608 °F)

SUPERCHARGING BY THE AXIAL COMPRESSOR (2.5 kg/s / 5.5 lbs/sec. ; 160 kPa / 23.2 PSI)

CENTRIFUGAL COMPRESSOR - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

COMBUSTION CHAMBER - GENERAL Function

Main components

The combustion chamber forms an enclosure in which the air-fuel mixture is burnt.

- Outer part (front swirl plate and mixer unit) - Inner part (rear swirl plate and shroud)

Position

- Fuel injection system

- Central section of the gas generator.

- Turbine casing.

Main characteristics - Type : annular with centrifugal fuel injection - Overall fuel-air ratio : 1/45 - Turbine inlet temperature : 1125 °C (2057 °F).



ENGINE

ARRIEL 1

Training Manual

OUTER PART Front swirl plate

Mixer unit

INNER PART Rear swirl plate

Shroud

Type : Annular with centrifugal fuel injection Overall fuel-air ratio : 1/45 Turbine inlet temperature : 1125 °C (2057 °F)

FUEL INJECTION SYSTEM

TURBINE CASING

COMBUSTION CHAMBER - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

COMBUSTION CHAMBER - DESCRIPTION The combustion chamber assembly includes the outer part, the inner part, the turbine casing and the fuel injection system.

Outer part The outer part includes the front swirl plate and the mixer unit. The front swirl plate is provided with calibrated orifices for the passage of primary air ; it is secured to the mixer unit with special rivets. The mixer unit is provided with calibrated orifices for the passage of dilution air ; it is bolted to the rear flange of the turbine casing. It includes the dilution tubes.

Inner part

Turbine casing The casing houses the combustion chamber and the turbine. It has various bosses and, particularly the boss for the combustion chamber drain valve at the bottom of the casing.

Fuel injection system The main fuel injection system includes : the fuel inlet union, the inner fuel tube, the fuel distributor and the centrifugal injection wheel. The injection wheel is mounted by means of curvic couplings between the compressor and the turbine shaft (refer to "FUEL SYSTEM" chapter for further details on the fuel injection system).

The inner part includes the rear swirl plate and the shroud. The rear swirl plate is provided with calibrated orifices for the passage of primary air. The shroud, integral with the rear swirl plate surrounds the shaft ; it is bolted to the turbine nozzle guide vane.

Note : The two parts are made of special alloy. The calibrated orifices are drilled using the electron beam process.



ENGINE

ARRIEL 1

Training Manual

FRONT SWIRL PLATE

TURBINE CASING

DILUTION TUBE MIXER UNIT REAR SWIRL PLATE

REAR SWIRL PLATE SHROUD

SHROUD

MIXER UNIT

Curvic-coupling

Drain valve

FRONT SWIRL PLATE FUEL INJECTION SYSTEM

TURBINE CASING

INJECTION WHEEL

COMBUSTION CHAMBER - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

COMBUSTION CHAMBER - OPERATION The combustion chamber forms an enclosure in which the fuel - air mixture is burnt.

Combustion chamber flow In the combustion chamber, the compressed air is divided into two flows : a primary air flow mixed with the fuel for combustion and a secondary air flow (or dilution air flow) for cooling of the burnt gases.

Secondary air The secondary air (or dilution air) flows through the orifices of the mixer unit and the dilution tubes. It is calibrated to obtain flame stability, cooling of the burnt gases, and distribution of temperature on the turbine. Gas

Primary air

The gas produced by the combustion is directed into the turbine nozzle guide vane.

One part flows through the orifices of the front swirl plate.

Operating parameters

A second part flows through the hollow vanes of the turbine nozzle guide vane (cooling of the vanes) and through the orifices of the rear swirl plate.

The fuel-air ratio for combustion is approximately 1/15 ; the total ratio is approximately 1/45.

The primary air is mixed with the fuel sprayed by the injection wheel. The combustion occurs between the two swirl plates. The flame temperature reaches approximately 2500 °C (4532 °F).


The pressure drop in the combustion chamber is approximately 4 %. The turbine inlet temperature (at design point) is approximately 1125 °C (2057 °F).


ENGINE

ARRIEL 1

Training Manual COMPRESSED AIR (820 kPa / 118.9 PSI ; 320 °C / 608 °F)

Primary air (combustion) Secondary air (cooling of burnt gases) Burnt gases

GAS FLOW TO THE TURBINE (1125 °C / 2057 °F)

FUEL INJECTION

COMBUSTION (2500 °C / 4532 °F) (pressure loss : 4 %)

COMBUSTION CHAMBER - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

GAS GENERATOR TURBINE - GENERAL Function

Main components

The turbine extracts sufficient energy from the gas flow to drive the compressors and the accessories.

- Rotating components (wheels, shafts, bearing)

Position

- Stationary components (nozzle guide vanes, containment shield, casing).

- At the rear of the gas generator.

Main characteristics - Type : two stage axial - Turbine inlet temperature : 1125 °C (2057 °F) - Turbine outlet temperature : 880 °C (1616 °F) - N1 speed ≈ 52000 RPM (100 %) ACW



ENGINE

ARRIEL 1

Training Manual

NOZZLE GUIDE VANES

WHEELS

BEARING

Type : Two stage axial Turbine inlet temperature : 1125 °C (2057 °F) Turbine outlet temperature : 880 °C (1616 °F) N1 speed 52000 RPM (100%) ACW

CONTAINMENT SHIELD

CASING

SHAFTS

GAS GENERATOR TURBINE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

GAS GENERATOR TURBINE DESCRIPTION The gas generator turbine assembly includes rotating components and stationary components.

The stationary components are the turbine nozzle guide vanes, the containment shield, the turbine casing and the diffuser casing.

Rotating components The main rotating components are the turbine wheels. The wheels consist of either a disc and fir-tree mounted blades or blades cut from the solid. The front wheel is coupled by curvic-couplings to the turbine shaft and to the second stage wheel. The rear wheel is coupled to a stub shaft by a curvic-coupling. The stub shaft is supported by a roller bearing. Rotating labyrinths provide sealing. A tie-bolt secures the rotating assembly.


Stationary components

The first stage nozzle guide vane includes a row of hollow vanes. It is mounted on the combustion chamber. The second stage nozzle guide vane includes a row of vanes mounted in a ring. The containment shield provides containment in case of blade failure. The turbine casing forms the housing of turbines and combustion chamber. The diffuser casing connects the gas generator and the power turbine and its hub contains the housing for the gas generator rear bearing. At the rear it houses the power turbine nozzle guide vane.


ENGINE

ARRIEL 1

Training Manual NOZZLE GUIDE VANES

TURBINE SHROUD

TURBINE WHEELS

DIFFUSER CASING

TURBINE CONTAINMENT SHIELD 2nd STAGE TURBINE WHEEL

BEARING (roller)

1st STAGE TURBINE WHEEL TURBINE SHROUD

TIE-BOLT

DIFFUSER CASING 2nd STAGE NOZZLE GUIDE VANE

REAR SHAFT 1st STAGE NOZZLE GUIDE VANE FRONT SHAFT FRONT SHAFT

TURBINE CASING

CONTAINMENT SHIELD

Curvic-coupling

GAS GENERATOR TURBINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

GAS GENERATOR TURBINE - OPERATION The gas generator turbine transforms the gas energy into mechanical power to drive the compressors and various accessories.

Operating parameters

The operation is characterized by the first phase of expansion.

- Turbine inlet temperature : 1125 °C (2057 °F)

The operation is characterised by the following parameters :

- Turbine outlet temperature : 880 °C (1616 °F)

Turbine gas flow The burnt gases first flow through the nozzle guide vanes. The gas velocity increases due to the convergent passage. The flow on the blades results in aerodynamic forces whose resultant causes the rotation of the wheel. The gases, still containing energy, are directed to the power turbine.



ENGINE

Training Manual

GAS FROM THE COMBUSTION CHAMBER (1125 °C / 2057 °F)

ARRIEL 1

GAS EXPANSION IN THE NOZZLE GUIDE VANE (convergent passage)

ROTATION Rotation

Nozzle guide vane

COMPRESSOR DRIVE (52000 RPM ; ACW 800 kW ; 1072 Shp)

Turbine wheel

GAS TO THE POWER TURBINE (880 °C / 1616 °F)

GAS GENERATOR TURBINE - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

POWER TURBINE - GENERAL Function

Main components

The turbine extracts the energy from the gas to drive the power shaft through the reduction gearbox.

- Rotating components (wheel, shaft, bearings) - Stationary components (nozzle guide vane, containment shield, casing).

Position - Between the gas generator and the reduction gearbox. It forms the module M04.

Main characteristics - Type : axial, single-stage - Turbine inlet temperature : 880 °C (1616 °F) - Turbine outlet temperature : 600 °C (1080 °F) - N2 speed at 100 % ≈ 41586 RPM, CW



ENGINE

ARRIEL 1

Training Manual NOZZLE GUIDE VANE

WHEEL

BEARINGS

Type : Axial, single stage Turbine inlet temperature : 880 °C (1616 °F) Turbine outlet temperature : 600 °C (1080 °F) N2 speed at 100% ≈ 41586 RPM (CW)

CONTAINMENT SHIELD

POWER TURBINE CASING

SHAFT

POWER TURBINE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

POWER TURBINE - DESCRIPTION The power turbine assembly forms the module M04. It includes rotating components and stationary components.

Stationary components The main stationary components are the turbine nozzle guide vane, the power turbine casing and the bearing housing.

Rotating components The main rotating component is the power turbine with its shaft. The wheel includes a disc (integral with the shaft) and firtree mounted blades. The shaft is supported by two bearings : a front roller bearing and two rear ball bearings. It is fitted with two phonic wheels The front bearing sealing is ensured by a pressurised labyrinth seal (pressurisation with compressor air directed to the power turbine through an external pipe and inner ducts).

The nozzle guide vane includes a row of hollow vanes. It is part of the module M03. The power turbine casing engages over the gas generator outlet diffuser and is bolted to the module M03. It comprises an outer casing and an inner hub supported by three struts. The bearing housing is installed in the inner hub of the casing. Its rear part engages in the reduction gearbox. The identification plate is located on the power turbine casing. A containment shield is fitted around the rear of the casing.

The power is transmitted to the reduction gear by a muff coupling.



ENGINE

ARRIEL 1

Training Manual

WHEEL

CONTAINMENT PRESSURISED FRONT LABYRINTH SHIELD BEARING SEAL

Identification plate REAR BEARING BEARING HOUSING SHAFT

LABYRINTH Muff coupling

POWER TURBINE CASING PHONIC WHEELS

BEARING HOUSING NOZZLE GUIDE POWER TURBINE VANE CASING

PHONIC WHEELS

WHEEL

POWER TURBINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

POWER TURBINE - OPERATION The power turbine transforms the gas energy into mechanical power to drive the reduction gearbox.

Operating parameters The operation is characterised by the following parameters :

The operation is characterised by the second phase of expansion.

- Rotation : CW - Turbine inlet temperature : 880 °C (1616 °F)

Turbine flow The gas supplied by the gas generator flows through the nozzle guide vane. In the nozzle guide vane, the gas velocity increases due to the convergent passage.

- Power extracted : depending on the version

The gases are directed onto the turbine wheel and the resultant of the aerodynamic forces on the blades causes the wheel to rotate. The gases are then expelled overboard through the exhaust pipe.



ENGINE

ARRIEL 1

Training Manual

ROTATION OF THE POWER TURBINE

GAS FROM THE GAS GENERATOR TURBINE (880 °C / 1616 °F)

REDUCTION GEARBOX DRIVE (CW)

Rotation

Nozzle guide vane

Turbine wheel

EXPANSION IN THE NOZZLE GUIDE VANE

GAS EXHAUST

POWER TURBINE - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

EXHAUST PIPE Function

Description

The exhaust pipe continues the expansion phase and expels the gas overboard.

The exhaust pipe, which has an elliptical outlet, is made from stainless steel. It is bolted to the rear flange of the power turbine casing with the containment shield.

Position - Behind the power turbine, around the reduction gear.

A heat shield is fitted between the exhaust pipe and the reduction gearbox to protect the gearbox from the exhaust heat.

Main characteristics

The exhaust pipe has a drain at the bottom.

- Type : Elliptical

Operation

- Non-modular part

Functionally it should be noted that the exhaust gas still contains a certain amount of energy which produces a small residual thrust of about 15 daN (33 lbs).

- Gas temperature : 600 °C (1080 °F) - Residual thrust : ≈ 15 daN (33 lbs).

Main components - Exhaust pipe - Heat shield.

Note : The exhaust pipe is considered to be an SRU.



ENGINE

ARRIEL 1

Training Manual

RESIDUAL THRUST (15 daN / 33 lbs)

EXHAUST PIPE

GAS FROM POWER TURBINE

GAS EXHAUST (600 °C ; 1080 °F)

HEAT SHIELD

REDUCTION GEARBOX

DRAIN

DESCRIPTION

OPERATION

EXHAUST PIPE For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

REDUCTION GEARBOX - GENERAL Function

Main components

The reduction gearbox provides a reduced speed output and transmits the drive forwards.

- Drive gear - Intermediate gear

Position

- Output gear

- At the rear of the engine

- Casings

- It forms the module M05.

- Hydraulic torquemeter.

Main characteristics - Type : 3 stages, helical gears - Output gear speed : 6000 RPM at 100 %.



ENGINE

ARRIEL 1

Training Manual

DRIVE GEAR

INTERMEDIATE GEAR MUFF COUPLING

HYDRAULIC TORQUEMETER

Type : 3 stages, helical gears OUTPUT GEAR

Output gear speed : 6000 RPM at 100%

CASINGS

REDUCTION GEARBOX - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

REDUCTION GEARBOX - DESCRIPTION The reduction gearbox module mainly includes three gears contained in two half casings.

Drive gear The drive gear is linked to the power turbine by a muff coupling. It is supported by two roller bearings.

Intermediate gear

Reduction gearbox casing The gears are housed in a light alloy gearbox formed by two half casings. A fork shaped steel plate is mounted on the front face of the casing to prevent rearward movement of the power turbine in the event of overspeed. The module identification plate is located at the bottom of the casing.

It is a double helical type gear : one gear meshes with the drive gear, the other one with the output gear. The torquemeter piston is fitted in its hub. The intermediate gear is supported by two roller bearings.

Output gear It is supported by a ball bearing at the front and a roller bearing at the rear. The hub is internally splined to receive the transmission shaft.



ENGINE

ARRIEL 1

Training Manual

Muff coupling

DRIVE GEAR

DRIVE GEAR

INTERMEDIATE GEAR

FRONT CASING INTERMEDIATE GEAR

TORQUEMETER PISTON

OUTPUT GEAR

FORK SHAPED PLATE


OUTPUT GEAR

REAR CASING

REDUCTION GEARBOX - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

REDUCTION GEARBOX - OPERATION The reduction gear provides a forward output drive at a reduced speed.

Operation of the reduction gear The drive gear is directly driven by the power turbine shaft (muff coupling drive). It transmits the movement to the intermediate gear which contains the hydraulic torquemeter. The intermediate gear drives the output gear which provides the power drive at a speed of approximately 6000 RPM, clockwise.



ENGINE

ARRIEL 1

Training Manual

DRIVE GEAR DRIVEN BY THE POWER TURBINE TORQUEMETER PISTON

DOUBLE INTERMEDIATE GEAR

TRANSMISSION SHAFT

OUTPUT GEAR

REDUCTION GEARBOX - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

TRANSMISSION SHAFT AND ACCESSORY GEARBOX Function The shaft transmits the power to the helicopter via the power off-take at the front of the engine. The accessory gearbox provides the drive for the engine accessories.

Position - Shaft beneath the engine - Accessory gearbox at the front of the engine - This assembly forms the module M01.



ENGINE

ARRIEL 1

Training Manual

ACCESSORY DRIVE SHAFT

CASINGS

TRANSMISSION SHAFT

POWER OFF-TAKE

TRANSMISSION SHAFT AND ACCESSORY GEARBOX For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

POWER TRANSMISSION SHAFT TWIN-ENGINE CONFIGURATION GENERAL - DESCRIPTION Function The shaft transmits the power to the front power off-take.

Position : - Lower part of the engine.

The front of the shaft is supported by a ball bearing in the accessory gearbox front casing. The triangular flange which forms the power off-take is splined onto the front of the transmission shaft and is secured by a nut. Sealing of the oil which lubricates the bearing is ensured by a carbon seal. Three oil tubes are located between the shaft and the protection tube.


The rear of the shaft is splined into the hub of the output gear of the reduction gear.

Hollow steel shaft.

Main components - Transmission shaft - Protection tube - Accessory drive gear - Power off-take.

Description The shaft transmits the power to the power off-take and accessory gearbox. The shaft is located in a protection tube bolted to the reduction gearbox at the rear and to the accessory gearbox at the front.



ENGINE

ARRIEL 1

Training Manual

SHAFT

POWER OFF-TAKE (triangular flange)

CARBON SEAL

BEARING

BEARING

OUTPUT GEAR

ACCESSORY DRIVE GEAR

OIL TUBE

PROTECTION TUBE

POWER TRANSMISSION SHAFT - TWIN-ENGINE CONFIGURATION GENERAL - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

POWER TRANSMISSION SHAFT SINGLE ENGINE CONFIGURATION GENERAL - DESCRIPTION Function The shaft transmits the power to the front and to the rear of the engine.

Position :

The front of the transmission shaft is supported by a ball bearing in the accessory gearbox front casing. A triangular flange is splined onto the front of the transmission shaft. Sealing of the oil which lubricates the bearing is ensured by a carbon seal. Three oil pipes are located within the protection tube.

- Lower part of the engine.

A free wheel is mounted on the triangular flange to drive the power drive shaft which drives the main gearbox and the tail rotor.

Main characteristics - Hollow steel shaft with coaxial drive shaft.

Lubrication of the free wheel and its bearing is by the oil contained in the free wheel housing, or by the oil system of the engine, according to the version.

Main components - Transmission shaft

The rear of the transmission shaft is splined into the hub of the output gear of the reduction gear.

- Protection tube - Accessory drive gear

The rear of the tail rotor drive shaft is supported by a ball bearing in the hub of the output gear. A carbon seal is fitted in the rear cover of the gearbox.

- Drive shaft - Free wheel.

Description The shaft transmits the power to the power drive shaft. The transmission shaft is located in a protection tube bolted to the reduction gearbox at the rear and to the accessory gearbox at the front. For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

ARRIEL 1

Training Manual

SEAL

BEARING

TRIANGULAR FLANGE

BEARING

SHAFT

TAIL ROTOR DRIVE

ACCESSORY DRIVE GEAR

POWER DRIVE SHAFT

FREE WHEEL

CARBON SEAL

CARBON SEAL

OIL TUBE

FRONT PART

REAR PART

POWER TRANSMISSION SHAFT - SINGLE ENGINE CONFIGURATION GENERAL - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

ACCESSORY GEARBOX - GENERAL Function

Main components

To provide the drive for the engine accessories.

- Accessory drive shaft

Position

- Accessory drive train

- At the front of the engine.

- Casings.

Main characteristics - Type of gears : • spur gear • bevel gear.



ENGINE

Training Manual

ARRIEL 1

ACCESSORY DRIVE SHAFT (N1)

FRONT CASING

ACCESSORY DRIVE TRAIN

REAR CASING Type of gears : Spur gear Bevel gear

ACCESSORY DRIVE GEAR (N2)

ACCESSORY GEARBOX - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

ACCESSORY GEARBOX DESCRIPTION (1) The accessory gearbox has four drives on the front face : • starter generator • fuel control unit N1 • fuel control unit N2 • main power shaft. and four mounting bolts on the upper part for attachment of the M02. It has 3 power drives on the rear face : • oil pump • N1 tachometer generator • N2 tachometer generator. and the protection tube mounting flange, and the accessory drive shaft passage on the upper part.



ENGINE

ARRIEL 1

Training Manual

MOUNTING BOLTS (4) ACCESSORY DRIVE SHAFT PASSAGE (N1)

N1 TACHOMETER GENERATOR

FUEL CONTROL UNIT N1 DRIVE

OIL PUMP

STARTER GENERATOR DRIVE

POWER DRIVE

FUEL CONTROL UNIT N2 DRIVE

PROTECTION TUBE MOUNTING FLANGE

N2 TACHOMETER GENERATOR

REAR VIEW

FRONT VIEW

ACCESSORY GEARBOX - DESCRIPTION (1) For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

ACCESSORY GEARBOX DESCRIPTION (2) The transmission shaft and the accessory box assembly constitutes the module M01 located at the engine lower part. The accessory gearbox includes a train of gears housed in a gearbox formed by two half casings made of light alloy. The gearbox is installed at the bottom of the axial compressor by means of four bolts. The starter-generator gear forms the engine breather. The fuel control unit N1 gear drives the oil pump at the rear. The fuel control unit N2 gear is driven by the gear on the transmission shaft. The engine front support casing is bolted onto the front face of the accessory gearbox. The module identification plate is fitted on the front face of the gearbox.



ENGINE

ARRIEL 1

Training Manual

DRIVE SHAFT (N1) BREATHER GEAR TRANSMISSION SHAFT GEAR (N2) FRONT CASING

REAR CASING

N1 FUEL CONTROL UNIT AND OIL PUMP DRIVE


N2 FUEL CONTROL UNIT

Identification plate FRONT SUPPORT CASING

ACCESSORY GEARBOX - DESCRIPTION (2) For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

ACCESSORY GEARBOX - OPERATION The operation is considered during engine starting and in normal running.

The gas generator drives the accessory gear train through the bevel gear located on the axial compressor shaft.

Operation during engine starting During starting, the starter motor drives the accessory gearbox and thus the gas generator rotating assembly. The compressors supply air to the combustion chamber and the starting sequence continues. At self-sustaining speed (approximately 45 % N1) the electrical supply to the starter motor is cut. The starter motor is then mechanically driven by the engine and operates as a generator to provide DC current to the aircraft electrical system.


Operation in normal running

The following accessories are driven : - Starter-generator - FCU : N1 and N2 - Oil pumps - Tachometer generator : N1 and N2.


ENGINE

ARRIEL 1

Training Manual

FWD STARTER MOTOR

FWD DRIVE SHAFT

DIRECT CURRENT GENERATOR

OPERATION DURING ENGINE STARTING

DRIVE SHAFT

OPERATION IN NORMAL RUNNING (N1 50 %)

ACCESSORY GEARBOX - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE

Training Manual

ARRIEL 1

4 - OIL SYSTEM - Oil system ...................................................................... - Lubrication .................................................................... - Oil tank .......................................................................... - Oil pumps ...................................................................... - Electrical magnetic plugs .............................................. - Oil filter ......................................................................... - Filter pre-blockage indicator ........................................ - Oil cooler ....................................................................... - Centrifugal breather ..................................................... - Magnetic plugs ............................................................... - Strainers ........................................................................ - Indicating devices .......................................................... - Oil pipes and ducts ........................................................


4.2 4.8 4.12 4.14 4.20 4.24 4.30 4.34 4.36 4.40 4.42 4.44 4.50 to 4.51


OIL SYSTEM

Training Manual

ARRIEL 1

OIL SYSTEM - GENERAL Function

Lubrication requirements

The oil system ensures lubrication and cooling of the engine.

Lubrication is required for the following components :

Position All the components are fitted on the engine except the tank and cooler.

- Gas generator front bearings • Axial compressor bearing • Centrifugal compressor bearing • Accessory drive bearing - Gas generator rear bearing


- Power turbine bearings - System type : variable pressure, full flow, dry sump, synthetic oil

- Reduction gearbox

- Max oil temperature : 115 °C (239 °F)

- Accessory drive gearbox.

- Min oil pressure : 90 or 130 kPa (13 or 18.85 PSIG) according to version - Max oil pressure : 800 kPa (116 PSIG) - Oil pressure : ≈ 300 kPa (43.5 PSIG) - Max oil consumption : 0.3 l/h or 0.15 l/h according to version.



OIL SYSTEM

ARRIEL 1

Training Manual

GAS GENERATOR

OIL SYSTEM

POWER TURBINE REAR BEARING

FRONT BEARINGS

FRONT BEARING

REAR BEARINGS

Engine lubrication and cooling

Type : Variable pressure, full flow, dry sump, synthetic oil Max temperature : 115 °C (239 °F) Min pressure : 90 or 130 kPa (13 or 18.85 PSIG) according to version Max pressure : 800 kPa (116 PSIG) Max consumption : 0.3 l/h or 0.15 l/h according to version

BEARINGS

GEARS

ACCESSORY DRIVE GEARBOX

BEARINGS

GEARS REDUCTION GEARBOX

OIL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL SYSTEM - DESCRIPTION The system contains all the components necessary for engine lubrication : tank, pumps, filter, strainers, cooler, breather and indicating devices.

Oil tank

Cooler The oil cooler cools the oil. It is supplied by the aircraft manufacturer.

Breather

The tank contains the volume of oil required to lubricate the engine. It is supplied by the aircraft manufacturer.

Oil pumps

The centrifugal breather separates the oil from the air/oil mist and vents the system.

Indicating devices

The pump pack contains one pressure pump and three scavenge pumps. The gear type pumps are driven by the accessory gearbox. The pressure pump is equipped with a pressure relief valve and in some versions a check valve.

- Oil temperature probe (aircraft manufacturer supply) - Pre-blockage indicator - Low oil pressure switch

Oil filter The filter retains any particles which may be present in the oil. It is provided with a by-pass valve and a pre-blockage indicator.

- Pressure transmitter - Magnetic plugs - Electrical magnetic plugs.

Strainers The strainers protect the scavenge pumps from debris in the system.



OIL SYSTEM

ARRIEL 1

Training Manual

AIRFRAME

Oil temperature probe

TANK

Low oil pressure switch

ENGINE

Pressure Relief valve

Pre-blockage indicator Check valve (some versions)

Check valve

CENTRIFUGAL BREATHER

By-pass valve

COOLER

Electrical magnetic plug

Pressure transmitter

Scavenge pumps

Pressure pump

Magnetic plug

FILTER


Magnetic plug

STRAINERS

OIL PUMPS

OIL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL SYSTEM - OPERATION The main functions of the oil system are : supply, scavenge, breathing and indicating.

Supply The pressure pump draws the oil from the tank and supplies the system. A pressure relief valve limits maximum pressure by returning oil to the pump inlet.

Scavenge After lubrication, the oil falls by gravity to the bottom of the sumps. The oil is then immediately drawn away by the scavenge pumps and returned to the tank through the oil cooler (dry sump system). The strainers protect the scavenge pumps against any particles which may be held in the oil.

The oil is then delivered through a check valve, the oil filter and a calibrated orifice to the engine sections which require lubrication :

Breathing

- Gas generator front bearings

The oil mist which results from lubrication is returned to the accessory gearbox, where the oil is separated from the air by a centrifugal breather which vents overboard.

- Gas generator rear bearing The gas generator rear bearing has a direct air vent. - Power turbine bearings

Indicating

- Reduction gearbox - Accessory gearbox and torquemeter (supply upstream of the calibrated orifice).

The system ensures the following indications : pressure, temperature, low pressure, electrical magnetic plug and filter pre-blockage.

The oil is sprayed by jets onto the parts to be lubricated.



OIL SYSTEM

ARRIEL 1

Training Manual

AIRFRAME

ENGINE


Pressure transmitter

CENTRIFUGAL BREATHER Temperature probe PRESSURE PUMP

FILTER

TANK COOLER

Check valve


Check valve

Magnetic plug


SCAVENGE PUMPS

SUPPLY

Magnetic plug

Calibrated orifice

STRAINERS SCAVENGE

BREATHING

AIR VENT

OIL SYSTEM - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

LUBRICATION (1) This section describes the lubrication of the engine parts : gas generator, power turbine, reduction gear and accessory drive train.

Scavenge. The oil falls by gravity to the bottom of the housing, through a tube in the bottom of the housing and is returned to the tank by a scavenge pump.

Gas generator front bearings

Breathing. The air/oil mist which results from lubrication passes out through a tube screwed into the top of the housing and is vented overboard.

Supply. The oil is taken by external pipe to the upper part of the axial compressor casing. It is supplied to a jet which sprays the oil onto the two compressor bearings and the accessory drive bevel gear.

Accessory gearbox Supply. The oil is supplied by an internal duct. It passes through ducts and jets to the accessory gearbox gears and bearings.

The bearing housing is sealed by labyrinth seals. Scavenge. The oil falls by gravity into the accessory gearbox from where it is drawn by a scavenge pump and returned to the tank. Breathing. The air/oil mist which results from lubrication passes into the accessory gearbox and is vented through the centrifugal breather.

Scavenge. The oil falls by gravity to the bottom of the gearbox casing. It is immediately drawn by the scavenge pump and returned to the tank via the oil cooler. Breathing. The oil/air vapours resulting from the lubrication pass to the centrifugal breather. Then, the deoiled vapours are vented overboard.

Gas generator rear bearing Torquemeter pressure Supply. The oil, taken by external pipe, passes through a restrictor and a tube screwed into the bearing housing and is sprayed onto the bearing.

Supply. The torque indicating system receives a supply of oil from the pump outlet via a restrictor and through a tube in the protection tube. This system is described in chapter 8.

The bearing housing is sealed by pressurised labyrinth seals.



OIL SYSTEM

ARRIEL 1

Training Manual

AXIAL COMPRESSOR BEARING

CENTRIFUGAL COMPRESSOR BEARING DIRECT AIR VENT

GAS GENERATOR REAR BEARING

AIR VENT

TORQUEMETER PRESSURE ACCESSORY GEARBOX

SCAVENGE

Supply

Torquemeter pressure

Scavenge

Air vent

LUBRICATION (1) For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

LUBRICATION (2) Power turbine bearings and reduction gearbox Supply. The oil is supplied via a tube located inside the transmission shaft protection tube. The bearings and gears are lubricated by jets via internal drillings in the casings. A labyrinth seal is fitted in front of the power turbine front bearing to seal the housing. Scavenge. The oil which has lubricated the power turbine bearings is returned to the reduction gearbox. The oil in the reduction gearbox falls to the bottom of the casing and is drawn by a scavenge pump, through a tube in the transmission shaft protection tube, and is returned to the tank.


Breathing. The air/oil mist resulting from lubrication passes through the protection tube, into the accessory gearbox where it passes through the centrifugal breather.

Torquemeter A tube in the protecting tube, connects the torque transmitter to the torquemeter piston in the intermediate gear of the reduction gearbox.


OIL SYSTEM

ARRIEL 1

Training Manual

POWER TURBINE BEARINGS

LUBRICATION OF THE REDUCTION GEARBOX (gears and bearings)

TORQUEMETER SUPPLY

BREATHING

SCAVENGE Supply Torquemeter pressure Scavenge Breathing

LUBRICATION (2) For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL TANK Function

Main components

The tank contains the oil required for engine lubrication.

- Filler cap

Position

- Level indicator

- On the aircraft : it is installed with the oil cooler above the plenum chamber, between the main gearbox and the front firewall.

- Drain plug (with magnetic plug) - Temperature probe - Unions (supply, return and vent).

Main characteristics - Aircraft manufacturer supply - Max capacity : 6 litres (1.56 US G)


Note : Refer to the aircraft manual for the description and operation.


OIL SYSTEM

ARRIEL 1

Training Manual FILLER CAP (provided with a dip stick)

Air vent

OIL COOLER

Aircraft supply

LEVEL INDICATOR

Oil return (from engine)

Max capacity : 6 litres (1.56 US G) TEMPERATURE PROBE DRAIN PLUG (with magnetic plug)

Tank drain

Engine oil supply

OIL TANK For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL PUMPS - GENERAL Function

Main components

The pumps ensure oil circulation.

- Drive shaft

Position

- Pump body (with one pressure pump, three scavenge pumps and valves).

- On the engine : the pump pack is mounted on the rear face of the accessory gearbox.

Main characteristics - Gear type - Pressure pump outlet pressure : ≈ 300 kPa (43.5 PSI) (variable pressure system) - Pressure relief valve setting : 800 kPa (116 PSI) - Check valve : according to version.



OIL SYSTEM

ARRIEL 1

Training Manual

PACK OF PUMPS

- Gas generator rear bearing scavenge pump - Reduction gearbox scavenge pump - Accessory gearbox scavenge pump - Pressure pump

Type : Gear Pressure pump outlet pressure : ≈ 300 kPa (43.5 PSI) (variable pressure system) Pressure relief valve setting : 800 kPa (116 PSI) Check valve : According to version

DRIVE SHAFT

PUMP BODY

OIL PUMPS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL PUMPS - DESCRIPTION The oil pump pack is mounted on the rear left face of the accessory gearbox and is driven at a speed proportional to N1. It consists of : - 4 gear type pumps : • Pressure pump • Gas generator rear bearing scavenge pump • Reduction gearbox scavenge pump • Accessory gearbox scavenge pump - The pump casing provided with inlet and outlet orifices - The pressure relief valve - The check valve (according to version).



OIL SYSTEM

ARRIEL 1

Training Manual

ACCESSORY GEARBOX SCAVENGE PUMP

REDUCTION GEARBOX SCAVENGE PUMP

GAS GENERATOR REAR BEARING SCAVENGE PUMP PRESSURE PUMP

CHECK VALVE DRIVE SHAFT

PUMP BODY

PRESSURE RELIEF VALVE

PUMP BODY

OIL PUMPS - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL PUMPS - OPERATION General The pressure pump draws the oil from the tank and pumps it to the filter. The scavenge pumps draw the oil from the casings and pump it to the cooler. Pressure relief valve operation If the oil pressure exceeds the valve setting the valve opens and allows the oil to return to the pump inlet. In normal operation the valve is closed and only opens in exceptional circumstances, e.g. starting with very low temperature. Pressure pump outlet check valve operation When the oil pressure is very low, e.g. engine stopped or at the beginning of start, the valve is closed in order to prevent flow between the pump and system.



OIL SYSTEM

ARRIEL 1

Training Manual

GAS GENERATOR REAR BEARING SCAVENGE PUMP Normal running condition (valve closed)

Overpressure (valve open)

REDUCTION GEARBOX SCAVENGE PUMP

ACCESSORY GEARBOX SCAVENGE PUMP

OPERATION OF THE PRESSURE RELIEF VALVE

Normal running condition (valve open) PRESSURE PUMP Engine stopped and initial phase of starting (valve closed)

PRESSURE RELIEF VALVE Suction - Overpressure

OPERATION OF THE CHECK VALVE

Pressure

Scavenge

OIL PUMPS - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

ELECTRICAL MAGNETIC PLUGS GENERAL Function

Main components

The electrical magnetic plugs provide a cockpit indication of metal particles in the oil system.

- Magnetic plug body - Electrical connector

Position

- Housing (strainer).

- In the system : • one downstream of the scavenge pumps • one upstream of the rear bearing scavenge pump - On the engine : • one near the pump assembly (scavenge pumps) • one on the left side of the accessory gearbox (rear bearing).

Note : The oil system also has two mechanical magnetic plugs located on the lower part of the accessory gearbox and on the lower part of the reduction gearbox.

Main characteristics - Type : • Magnetic with electrical indication • Self-sealing housing.



OIL SYSTEM

Training Manual

ARRIEL 1

HOUSING

MAGNETIC PLUG BODY

Type : Electrical magnetic plug Housing : Self-sealing ELECTRICAL CONNECTOR

ELECTRICAL MAGNETIC PLUGS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

ELECTRICAL MAGNETIC PLUGS DESCRIPTION - OPERATION Description

Operation

The electrical magnetic plugs comprise a magnetic probe which has two parts which are electrically insulated from one another and have a small gap between them.

The magnetic probe attracts magnetic particles present in the oil.

A resistor is connected across the gap. The plugs are connected, via the engine electrical harness, to the aircraft instrument panel with an optional test system.

If it attracts sufficient particles to form a bridge across the gap, this will complete the electrical circuit between the two magnetic parts and thus illuminate an indicator on the instrument panel.

The plugs are fitted into a housing which is provided with a self-sealing valve.

The resistor is fitted to allow the installation of a test circuit.

The scavenge oil flows across the magnetic probe. Note : Refer to aircraft documents for further details.



OIL SYSTEM

ARRIEL 1

Training Manual

Firewall

AIRCRAFT

ELECTRICAL CONNECTOR

Gap

+

44

GAP

2 3 1

26

60 KΩ

PLUG BODY

ENGINE

P003 O'RING SEAL MAGNETIC PLUG

+

44

SELF SEALING VALVE

2 3 1

26

60 KΩ

HOUSING

Resistor

P003 LIGHT "ON" BRIDGE OF PARTICLES

DESCRIPTION

OPERATION

ELECTRICAL MAGNETIC PLUGS - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL FILTER - GENERAL Function

Main components

The filter retains particles that may be in the oil.

- Filter base

Position

- Pre-blockage indicator

- In the system : downstream of the pressure pump

- Cover

- On the engine : on the left rear face of the accessory gearbox.

- By-pass valve.

Main characteristics - Type : metal cartridge - Filtering ability : 30 microns - Mechanical pre-blockage indicator : ∆P 150 kPa (21.7 PSID) - By-pass valve : • Setting : ∆P 200 kPa (29 PSID).



OIL SYSTEM

Training Manual

ARRIEL 1

COVER

FILTER BASE

Type : Metal cartridge Filtering ability : 30 microns

BY-PASS VALVE

PRE-BLOCKAGE INDICATOR

Mechanical pre-blockage indicator : ∆P 150 kPa (21.7 PSID) By-pass valve : ∆P 200 kPa (29 PSID)

OIL FILTER - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL FILTER - DESCRIPTION Description The main components of the filtering unit are the following : - Filter base - Filter cover - Metal cartridge (filtering element) - By-pass valve (fitted inside the filter base) - Drain valve. The filter base incorporates mounting points for the following : - Pre-blockage indicator - Low oil pressure switch - Oil pressure transmitter.



OIL SYSTEM

ARRIEL 1

Training Manual

FILTERING ELEMENT

FILTER COVER

BY-PASS VALVE

LOW OIL PRESSURE SWITCH

DRAIN VALVE

FILTER BASE

OIL PRESSURE TRANSMITTER


OIL FILTER - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL FILTER - OPERATION Operation Filtering (normal condition) The oil supplied by the pressure pump passes through the filter from outside to inside. The filtered oil then passes to the engine for lubrication. Pre-blockage If the filter begins to become blocked the pressure difference across the filter increases. At a given difference (150 kPa ⁄ 21.7 PSID) a red mechanical indicator pops out. The oil continues to flow through the filter. Blockage If the pressure difference exceeds 200 kPa (29 PSID), the by-pass valve opens and unfiltered oil passes to the system.



OIL SYSTEM

ARRIEL 1

Training Manual

OPERATION OF THE MECHANICAL PRE-BLOCKAGE INDICATOR (∆P 150 kPa / 21.7 PSID)

OIL FILTER ASSEMBLY

PRE-BLOCKAGE

FILTERING (30 microns)

NORMAL CONDITION

BLOCKAGE

OPERATION OF THE BY-PASS VALVE (∆P 200 kPa / 29 PSID)

OIL FILTER - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

FILTER PRE-BLOCKAGE INDICATOR GENERAL Function

Main components

The indicator indicates the onset of filter blockage.

- Indicator body

Position

- Indicator

On the left face of the filter housing.

- O'ring seals.

Main characteristics - Type : differential - Setting : ∆P 150 kPa (21.7 PSID) - Indication : red indicator - Manual rearming.



OIL SYSTEM

ARRIEL 1

Training Manual

INDICATOR BODY

O'RING SEALS

Type : Differential Setting : ∆P 150 kPa (21.7 PSID) Indication : Red indicator Manual rearming

INDICATOR

FILTER PRE-BLOCKAGE INDICATOR - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

FILTER PRE-BLOCKAGE INDICATOR DESCRIPTION - OPERATION Description

Operation

The pre-blockage indicator comprises the following parts :

Normal position

- Indicator body including : • Filter upstream pressure inlet • Filter downstream pressure inlet

Filter downstream pressure plus spring pressure is greater than upstream pressure. The two pistons are held together by magnetic force. The indicator is not visible.

- Red indicator piston

Pre-blockage

- ∆P piston

Filter upstream pressure exceeds downstream plus spring pressure and the ∆P piston displaces.

- Transparent cover

This breaks the magnetic hold and the indicator piston is pushed out by its spring. The indicator is visible.

- Thermal lock - O'ring seals ensure the filter pre-blockage indicator sealing.

The bi-metallic thermal lock ensures that the indicator doesn't operate when a large ∆P is caused by low temperature (locked below 50 °C (122 °F)). It is rearmed by removing the cover and pushing in the indicator.



OIL SYSTEM

ARRIEL 1

Training Manual

INDICATOR BODY

O RING SEALS

TRANSPARENT COVER

< 50°C (122°F)

Downstream pressure > 50°C (122°F)

RED INDICATOR

Upstream pressure NORMAL CONDITION

FILTER DOWNSTREAM PRESSURE

Red indicator "out" FILTER UPSTREAM PRESSURE

∆P PISTON

Downstream pressure

THERMAL LOCK Upstream pressure

∆P > 150 kPa (21.7 PSID)

PRE-BLOCKAGE CONDITION

DESCRIPTION

OPERATION

FILTER PRE-BLOCKAGE INDICATOR - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL COOLER Function

Main components

The oil cooler cools the oil after it has passed through the engine.

- Oil cooler - By-pass thermostatic valve

Position

- Unions (oil inlet and outlet).

- In the system : between the scavenge pumps and the tank - On the aircraft : it is installed on the oil tank above the plenum chamber between the main gearbox and the front firewall.

Main characteristics - Type : air-oil cooler - By-pass thermostatic valve : 276 kPa (40 PSI) : • Full open when t° < 57 °C (135 °F) • Full closed when t° > 67 °C (153 °F) - Supplied by aircraft manufacturer.



OIL SYSTEM

ARRIEL 1

Training Manual

OIL TANK

BY-PASS THERMOSTATIC VALVE

Oil inlet (from scavenge pumps)

OIL COOLER Aircraft component Type : Air/oil cooler By-pass Thermostatic valve : 276 kPa (40 PSI) - Full open when : t° < 57 °C (135 °F) - Full closed when : t° > 67 °C (153 °F) FAN

Ambient air

OIL COOLER For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

CENTRIFUGAL BREATHER - GENERAL Function

Main components

The centrifugal breather separates the oil from the air/oil mist created by the oil system.

- Gear wheel with air passage holes - Splines for the starter generator drive.

Position It is formed by the starter/generator drive gear in the accessory gearbox.

Main characteristics - Type : centrifugal - De-oiled air : through the rear of the hollow shaft.



OIL SYSTEM

Training Manual

ARRIEL 1

DE-OILED AIR

OIL MIST

Type : Centrifugal De-oiled air : Through the rear of the hollow shaft SPLINES FOR THE STARTER GENERATOR DRIVE GEAR PROVIDED WITH BREATHER HOLES

CENTRIFUGAL BREATHER - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

CENTRIFUGAL BREATHER - DESCRIPTION OPERATION Description

Operation

The centrifugal breather is formed by the starter generator drive gear. This gear is formed in one piece with a hollow shaft and has holes which provide a passage between the gearbox and the air vent.

The centrifugal breather is driven by the intermediate gear of the accessory drive.

The gear is supported by two ball bearings and has a magnetic carbon seal at each end. The breather air outlet is at the rear end of the shaft, where the air passes into the gearbox outlet.


When the engine is running, the air/oil mist passes through the breather : - Centrifugal force throws the oil droplets out into the gearbox where they fall to the bottom of the casing - The de-oiled air passes out through the shaft, via a gearbox passage, into an external pipe which discharges into the exhaust.


OIL SYSTEM

ARRIEL 1

Training Manual

OIL MIST - from accessory gearbox - from gas generator bearings - from power turbine bearings - from reduction gearbox

AIR VENT

DE-OILED AIR MAGNETIC CARBON SEAL


MAGNETIC CARBON SEAL

BEARING

BEARING OIL DROPLETS

CENTRIFUGAL BREATHER - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

MAGNETIC PLUGS Function

Main components

The magnetic plugs retain magnetic particles contained in the oil to provide a rapid and frequent check of the internal condition of the engine.

- Self sealing housing : • Housing • O'ring seal • Valve • Spring

Position In the system :

- Magnetic plug : • Magnet • O'ring seals • Locating pins.

- One on the reduction gearbox scavenge return - One on the accessory gearbox scavenge return. On the engine : - One at the bottom of the reduction gearbox - One at the bottom of the accessory gearbox. They are mounted on the left or the right side according to the position of the engine in the helicopter.

Main characteristics - Type : single magnetic pole. Self-sealing housing.



OIL SYSTEM

ARRIEL 1

Training Manual

VALVE

O'RING SEAL HOUSING

LOCATING PINS

O'RING SEALS

NORMAL POSITION SPRING

MAGNET

Type : Single magnetic pole Self-sealing housing MAGNET

LOCATING PIN

O'RING SEALS

MAGNETIC PLUG

REMOVED POSITION

MAGNETIC PLUGS For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

STRAINERS Function

Main components

The strainers protect the scavenge pumps against large particles which might be in the oil.

- Strainer body - Wide mesh filter

Position

- Mounting flange

- In the system : they are fitted in each scavenge line upstream of the scavenge pump

- O'ring seal.

- On the engine : • Two strainers are located on the accessory gearbox casing (reduction gearbox and accessory gearbox scavenge) • One strainer is located on the oil pump assembly (gas generator rear bearing scavenge)

Functional description A strainer is a wide mesh filter which retains any large particles which may be present in the oil in order to protect the scavenge pumps.

Main characteristics - Type : wide mesh filter.

Note : The rear bearing strainer is fitted in the electrical magnetic plug housing (TU 208).



OIL SYSTEM

ARRIEL 1

Training Manual

Gas generator rear bearing scavenge strainer Type : Wide mesh filter

Accessory gearbox scavenge strainer ACCESSORY GEARBOX STRAINER

GAS GENERATOR REAR BEARING STRAINER (After Mod. TU 208)

Reduction gearbox scavenge strainer

GAS GENERATOR REAR BEARING STRAINER

REDUCTION GEARBOX STRAINER

ACCESSORY GEARBOX AND REDUCTION GEARBOX STRAINERS

GAS GENERATOR REAR BEARING STRAINER (Before Mod. TU 208)

STRAINERS For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

LOW OIL PRESSURE SWITCH - GENERAL Function

Main components

The low oil pressure switch detects low oil system pressure and provides cockpit indication.

- Pressure switch body - Electrical connector

Position

- Mounting flange.

- In the system : downstream of the filter - On the engine : mounted on the filter base.

Main characteristics - Type : diaphragm pressure switch - Setting : 90 or 130 kPa (13 or 18.9 PSI) (according to version) - Indication : warning light on instrument panel.



OIL SYSTEM

Training Manual

ARRIEL 1


PRESSURE SWITCH BODY

MOUNTING FLANGE

Type : Diaphragm pressure switch Setting : 90 or 130 kPa (13 or 18.9 PSI) according to version Indication : Light on instrument panel

LOW OIL PRESSURE SWITCH - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

LOW OIL PRESSURE SWITCH DESCRIPTION - OPERATION Description

Operation

The pressure switch comprises the following components :

The pressure switch microswitch is open during normal engine operation.

- A diaphragm, subjected to the oil pressure downstream of the filter - A plunger, fixed to the diaphragm, to operate a microswitch - An electrical contact connected to a warning light on the instrument panel

If the oil pressure downstream of the filter reduces to less than 90 or 130 kPa (13 or 18.9 PSI) according to version, the diaphragm moves down. This causes the electrical contact to close, completing the circuit of the low oil pressure warning light.

The pressure switch is secured by means of three screws on the filter base. An O'ring seal ensures the sealing between the pressure switch and the filter base.



OIL SYSTEM

ARRIEL 1

Training Manual Firewall

AIRCRAFT

ENGINE CONTACT OPEN (normal oil pressure)

ELECTRICAL CONTACT

WARNING LIGHT (instrument panel)

+28 VDC

+28 VDC

2 1 3

LOW OIL PRESSURE SWITCH

PLUNGER DIAPHRAGM +28 VDC

From filter

2 1 3

To lubrication LIGHT "ON" (instrument panel)

DESCRIPTION

CONTACT CLOSED (low oil pressure, min<130 kPA / 18.9 PSI)

OPERATION

LOW OIL PRESSURE SWITCH - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL PRESSURE TRANSMITTER Function

Description

The transmitter provides a signal of oil pressure to the instrument panel.

The transmitter includes : - The transmitter body

Position

- An electrical connector.

- In the system : in the supply system, downstream of the filter

Operation

- On the engine : screwed into the filter base.

Main characteristics - Type : inductive or resistive according to version

The inductive type transmitter is provided with a piston connected to a push rod which has a core at its end. As oil pressure increases the piston is pushed up, moving the core in a coil, causing a voltage output proportional to the pressure.

- Output signal : voltage proportional to the oil pressure - Supplied by the aircraft manufacturer.



OIL SYSTEM

ARRIEL 1

Training Manual


TRANSMITTER BODY

DESCRIPTION

Aircraft component Type : Inductive or resistive (according to version) Output signal : Voltage proportional to the oil pressure

COIL

PISTON

OPERATION

OIL PRESSURE TRANSMITTER For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

OIL PIPES AND DUCTS This description includes external pipes and internal passages of the oil system.

Supply to the power turbine bearings and reduction gearbox

Pipelines - General

- Internal passage - Tube inside the output shaft protection tube.

- Type of pipelines : rigid.

Accessory gearbox supply

Tank to pressure pump

- Internal passages.

- Flexible pipeline supplied by the aircraft manufacturer - Union on the pressure pump.

Scavenge, engine front end - Internal passages.

Pressure pump to filter

Scavenge, gas generator rear bearing

- Internal passage in the casing.

- External pipe - Union on pump.

Filter to system - Internal passage in the accessory gearbox casing.

Supply to the gas generator front bearings - External pipe - Union on the compressor casing.

Supply to the gas generator rear bearing - External pipe.

Scavenge, engine rear part (power turbine and reduction gear) - Tube within output shaft protection tube - Internal passages.

Breathing - Gas generator front bearings - into accessory gearbox - Gas generator rear bearing - external pipe overboard - Reduction gearbox and power turbine - internal into accessory gearbox.

Vent - External pipe to the exhaust pipe - External pipe from gas generator rear bearing overboard.



OIL SYSTEM

ARRIEL 1

Training Manual

TANK TO PUMP

SCAVENGE TO COOLER AND TANK

PUMP TO FILTER

FILTER TO ENGINE

BREATHER

REAR BEARING VENT

SCAVENGE TO PUMPS

OIL PIPES AND DUCTS For training purposes only © Copyright - TURBOMECA - 2000


OIL SYSTEM

Training Manual

ARRIEL 1

5 - AIR SYSTEM - Air system ...................................................................... 5.2 - Internal air system......................................................... 5.4 - Air tappings ................................................................... 5.8 - Compressor bleed valve ................................................ 5.10 - Air tapping unions ........................................................ 5.18 - Air pipes ......................................................................... 5.20 to 5.21



AIR SYSTEM

Training Manual

ARRIEL 1

AIR SYSTEM Function The engine air system includes : - An internal air system which ensures : • The pressurisation of the labyrinth seals • The cooling of the engine internal parts • The balance of forces on the rotating assemblies - Air tappings which ensure : • Bleed valve operation • Start injector ventilation • Aircraft air system supply • Air supply to the FCU metering unit - The compressor bleed valve.

Note : Refer to the various systems for the location, characteristics and operation.



AIR SYSTEM

Training Manual

AIR TAPPINGS - Start injector ventilation - Bleed valve operation - Aircraft air system supply - Air supply to the FCU metering unit

ARRIEL 1

INTERNAL AIR SYSTEM - Pressurisation of labyrinth seals - Cooling of internal parts - Balance of forces on the rotating assemblies

COMPRESSOR BLEED VALVE

AIR SYSTEM For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

INTERNAL AIR SYSTEM - GENERAL Function

Main components

The internal air system pressurises the labyrinth seals, cools certain parts and provides a balancing of forces.

- Internal passages

Position All the parts of the system are internal except the pressurisation of the power turbine labyrinth which is supplied by an external pipe.

- Calibrated orifices - External pipe for the power turbine labyrinth pressurisation.

Main characteristics - Type : air pressure tapping with a calibrated flow - Axial compressor outlet pressure : 160 kPa (23.2 PSI) - Centrifugal compressor outlet pressure : 820 kPa (118.9 PSI) - Air flow : ≈ 2 % of the engine total flow.



AIR SYSTEM

ARRIEL 1

Training Manual

INTERNAL AIR SYSTEM - Internal passages - Calibrated orifices

External pipe for the power turbine labyrinth pressurisation

Type : Air pressure tapping with a calibrated flow Axial compressor outlet pressure : 160 kPa (23.2 PSI) Centrifugal compressor outlet pressure : 820 kPa (118.9 PSI) Air flow : ≈ 2 % of engine total flow

INTERNAL AIR SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

INTERNAL AIR SYSTEM - FUNCTIONAL DESCRIPTION The internal air system can be considered in three parts : the front section, the gas generator HP section and the power turbine section.

Front section Air tapped from the centrifugal compressor inlet is used to pressurise the front bearing labyrinths. There is a very small flow of air into the bearing chamber.

The air from the centrifugal compressor outlet flows through the hollow nozzle guide vanes (1st stage) and through holes in the shroud. It is used to cool the nozzle guide vane and the front face of the gas generator turbine. The centrifugal compressor casing is fitted with air tapping points. This air is called clean air as it is out of the main air flow stream.

Power turbine section Air tapped from the same point is discharged through the compressor bleed valve, mounted on the compressor casing (see compressor bleed valve).

Gas generator section Air tapped from the centrifugal compressor tip passes down the rear face of the compressor wheel, through the curvic couplings, the hollow shaft and internal passages. It is used to :

Air tapped from the combustion chamber is taken by an external pipe to the reduction gearbox casing. It then passes through internal passages to pressurise the labyrinth seal on the power turbine shaft and to cool the rear face of the power turbine. A circulation of P0 air, induced by venturi effect, cools the gas generator rear bearing chamber, and then flows through the power turbine nozzle guide vanes, cooling them and then joins the gas flow.

- Cool the front and rear faces of the gas generator turbines (discharging into the gas flow) - Pressurise the labyrinth seals of the gas generator rear bearing (small flow into the bearing housing) and the injection wheel.



AIR SYSTEM

ARRIEL 1

Training Manual

P0

FRONT SECTION

GAS GENERATOR SECTION

POWER TURBINE SECTION

INTERNAL AIR SYSTEM - FUNCTIONAL DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

AIR TAPPINGS Function

Aircraft services

Air tappings are used for :

Compressor delivery air is tapped off for use in various aircraft systems.

- Fuel control - Start injector ventilation

The engine has two air tapping unions (used for the aircraft services) on the centrifugal compressor casing.

- Aircraft services

Note : The use of this bleed is restricted during take-off.

- Bleed valve operation

Bleed valve operation

- Air intake anti-icing.

Compressor delivery air is tapped to operate the compressor bleed valve.

Fuel control P2 air is used for the acceleration control unit and the min fuel flow limiter (in some versions 1C, 1D, 1M, ... ). The system includes a pressure tapping and a pipe between the tapping union and the FCU. Start injector ventilation

Air intake anti-icing On the 1S version P2 air is used for air intake anti-icing. The system includes an air tapping point, a pipeline which passes forward through the front firewall, an electrovalve, a pressure switch and the double skinned air intake duct.

Compressor delivery air is used to ventilate the start injectors to avoid blockage by the carbonisation of unburnt fuel. The system comprises a tapping union and a pipe connected to the start electro-valve.



AIR SYSTEM

Training Manual

ARRIEL 1

AIRCRAFT SERVICES AND AIR INTAKE ANTI-ICING (1S) P0 P0 P2

SIGNAL FOR THE FUEL CONTROL

P2

BLEED VALVE OPERATION

START INJECTOR VENTILATION

AIR TAPPINGS For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

COMPRESSOR BLEED VALVE - GENERAL Function

Principle

The compressor bleed valve prevents axial compressor surge.

The valve prevents compressor surge by bleeding off a certain quantity of air tapped from the axial compressor outlet. When the valve is open, the discharge of air causes the air flow through the axial compressor to increase thus moving the working line away from the surge line.

Position - In the system : between the axial and centrifugal compressors - On the engine : at the top of the counter-casing.

Main characteristics - Type : pneumatic or electrical (according to version) - Control : • by P2/P0 pressure ratio (pneumatic type) • as a function of N1 (electrical type). Note : The air can be discharged under the cowling in order to improve cooling of the engine compartment.



AIR SYSTEM

ARRIEL 1

Training Manual

Type : Pneumatic or electrical (according to version) Control : - P2/P0 pressure ratio (pneumatic type) - As a function of N1 (electrical type) P1' : AIR DISCHARGED THROUGH THE COMPRESSOR BLEED VALVE

P2/P0 Surge line

COMPRESSION AND STRAIGHTENING OF THE AIR

ADMISSION OF AMBIENT AIR

Working line (valve closed)

Working line (valve open)

G

COMPRESSOR BLEED VALVE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

ELECTRO-PNEUMATIC COMPRESSOR BLEED VALVE DESCRIPTION - OPERATION Description

Operation

This compressor bleed valve includes 3 main parts : the tachometer box, the control electro-valve and the bleed valve.

Closing

Tachometer box It operates a relay controlled by a speed signal from the N1 tachometer transmitter.

Control electro-valve It admits P2 air to close the valve when it is electrically supplied.

When the N1 reaches 96 % the tachometer box closes the electrical contact which actuates the control electro-valve to the open position. P2 pressure pushes the piston which closes the bleed valve. Opening When the N1 decreases below 94 %, the tachometer box opens the electrical contact and the spring moves the electro-valve to the closed position. The spring pushes the piston which opens the bleed valve.

Bleed valve It includes a spring loaded piston subjected to P2 pressure. The piston operates the valve.



AIR SYSTEM

ARRIEL 1

Training Manual BLEED VALVE TACHOMETER BOX P2

+ P1'

N1 96%

94%

P2 AIR SUPPLY GRILL ON P1' AIR DISCHARGE

CONTROL ELECTRO-VALVE

ELECTRO-PNEUMATIC COMPRESSOR BLEED VALVE DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

PNEUMATIC COMPRESSOR BLEED VALVE DESCRIPTION - OPERATION The compressor bleed valve includes 3 main parts : the detection capsule, the intermediate stage and the bleed valve.

Operation

Detection capsule

When the gas generator rotation speed N1 increases, the compression ratio P2/P0 increases and beyond a certain value :

It is subjected to P2/P0 pressure ratio and controls the air leak downstream of the calibrated orifice B.

Closing

- The pressure becomes sufficient to deform the detection capsule which closes the leak

It is fitted with a filter at the inlet.

Intermediate stage

- The pressure downstream of the calibrated orifice B increases

It includes a diaphragm which is subjected to the pressure downstream of B. The diaphragm controls the leak which determines the pressure downstream of the calibrated orifice A.

Bleed valve It includes a spring loaded piston subjected to a downstream pressure. The piston opens or closes the P1' air passage.

- The diaphragm of the intermediate stage closes the leak - The pressure downstream of the calibrated orifice A increases - The piston moves down under P2 pressure and the valve closes and stops the P1' air discharge. Opening

It also includes a microswitch, operated by the piston, which provides indication of the bleed valve position.

The P2/P0 ratio is not sufficient to activate the capsule and there is an air leak downstream of the calibrated orifices. The piston is not actuated and the valve is open. A certain amount of air, tapped from the centrifugal compressor inlet, is discharged overboard.



AIR SYSTEM

ARRIEL 1

Training Manual

BLEED VALVE

INTERMEDIATE STAGE

DETECTION CAPSULE

FILTER

P2 A

INTERMEDIATE STAGE

B

DETECTION CAPSULE FILTER

P0 P1'

P1'

MICROSWITCH

INDICATOR

BLEED VALVE

PNEUMATIC COMPRESSOR BLEED VALVE DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

BUTTERFLY TYPE COMPRESSOR BLEED VALVE - DESCRIPTION - OPERATION Description

Operation

The compressor bleed valve includes 3 main parts : the detection capsule, the intermediate stage and the bleed valve.

Closing

Detection capsule

When the gas generator rotation speed N1 increases, the compression ratio P2/P0 increases and beyond a certain value :

It is subjected to P2/P0 pressure ratio and controls the air leak downstream of the calibrated orifice B.

- The pressure becomes sufficient to deform the detection capsule which closes the leak

It is fitted with a filter at the inlet.

- The pressure downstream of the calibrated orifice B increases

Intermediate stage

- The diaphragm of the intermediate stage closes the leak

It includes a diaphragm which is subjected to the pressure downstream of B. The diaphragm controls the leak which determines the pressure downstream of the calibrated orifice A. Bleed valve

- The piston moves down under P2 pressure and rotates the butterfly valve through the rack and pinion mechanism. The valve closes and stops the air discharge. Opening

It includes a spring loaded piston subjected to pressure downstream of orifice A. The piston actuates the butterfly valve by means of a rack and pinion mechanism. It also includes a microswitch, operated by the piston, which gives the position of the bleed valve by means of a light ("on" valve "open").


- The pressure downstream of the calibrated orifice A increases

The P2/P0 ratio is not sufficient to activate the capsules and there is an air leak downstream of the calibrated orifices. The piston is not actuated and the butterfly valve is open. A certain amount of air, tapped from the centrifugal compressor inlet, is discharged overboard.


AIR SYSTEM

ARRIEL 1

Training Manual

P2 AIR

A

B FILTER P0 AIR

PISTON

MICROSWITCH

DETECTION CAPSULE INTERMEDIATE STAGE P1'

BUTTERFLY VALVE RACK

PINION

BUTTERFLY COMPRESSOR BLEED VALVE DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

AIR TAPPING UNIONS These pages summarise the various air tappings : start injector ventilation, bleed valve control, power turbine labyrinth pressurisation, aircraft supply.

Compressor bleed valve

They are located on the centrifugal compressor casing front face. The air in this zone is considered clean air as it is out of the main air stream and thus contains very little debris.

Air flow : negligible.

At 100 % N1, in standard conditions, this air has a pressure of 820 kPa (118.9 PSI) and a temperature of 320 °C (608 °F).

Union (ø 1.9 mm).

Metering unit supply (FCU) Union (ø 1.9 mm). Air flow : nil.

Start injector ventilation Union with a restrictor (ø 1 mm). Air flow : very low.

Power turbine labyrinth pressurisation Union (ø 1.9 mm). Air flow : very low.

Aircraft services Union. Air flow : 100 g/s (0.22 lb/sec.) Max.



AIR SYSTEM

ARRIEL 1

Training Manual

AIR BLEED FOR AIRCRAFT SYSTEM SUPPLY TO CONTROL THE COMPRESSOR BLEED VALVE SUPPLY TO FUEL CONTROL UNIT

Ø1,9 mm

Ø1 mm

Ø1,9 mm SUPPLY FOR POWER TURBINE LABYRINTH PRESSURISATION SUPPLY FOR VENTILATION OF THE START INJECTORS AIR BLEED FOR AIRCRAFT SYSTEM

7 holes Ø1,5 mm

AIR TAPPING UNIONS For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

AIR PIPES This part considers the external air pipes of the air system.

Pipes - General - Type of pipes : stainless steel, rigid - Type of unions : QUINSON union.

P2 air pipe for the control of the compressor bleed valve Air pipe to supply the Fuel Control Unit Air pipe for the ventilation of the start injectors Air pipe for the pressurisation of the power turbine labyrinth.



AIR SYSTEM

Training Manual

P2 AIR PIPE FOR THE COMPRESSOR BLEED VALVE CONTROL

AIR PIPE TO SUPPLY THE FUEL CONTROL UNIT

ARRIEL 1

AIR PIPE FOR THE VENTILATION OF THE START INJECTORS

AIR PIPE FOR THE PRESSURISATION OF THE POWER TURBINE LABYRINTH

AIR PIPES For training purposes only © Copyright - TURBOMECA - 2000


AIR SYSTEM

Training Manual

ARRIEL 1

6 - FUEL SYSTEM - Fuel system ..................................................................... - Fuel Control Unit........................................................... • Fuel pump ................................................................................... • Fuel filter ..................................................................................... • Manual control ........................................................................... • Metering unit .............................................................................. - Overspeed and drain valve ........................................... - Start injector electro-valve ........................................... - Main injection system ................................................... - Start injectors ................................................................ - Combustion chamber drain valve ................................ - Fuel pipes........................................................................


6.2 6.12 6.14 6.18 6.24 6.28 6.30 6.36 6.42 6.46 6.50 6.54 to 6.55


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL SYSTEM - GENERAL (1) Function

Main components

The fuel system ensures fuel supply, injection, distribution and metering.

- Fuel control unit • Fuel pump • Filter • Valves • Metering unit.

Position All the system components are mounted on the engine except the tachometer box (twin-engine configuration).

- Overspeed and drain valve


- Start injector electro-valve

- Supply by the aircraft system and the engine pump

- Injection system.

- Centrifugal main injection and start injection by injectors - Manual control - Fuel control : hydromechanical controlling and metering device.



FUEL SYSTEM

ARRIEL 1

Training Manual

TACHOMETER BOX (TWIN-ENGINE VERSION)

START INJECTOR ELECTRO-VALVE

START INJECTORS

INJECTION WHEEL AIRCRAFT TANK

F.C.U.

OVERSPEED AND DRAIN VALVE

FUEL SYSTEM - GENERAL (1) For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL SYSTEM - GENERAL (2) Low pressure fuel system (1S, 1E versions)

Functional description

Function

The ejector pump is supplied with fuel from the HP pump via the astatic valve which opens at a pressure of 550 kPa. The ejector pump ensures a positive supply of fuel to the HP pump inlet.

This system is designed for aircraft without a booster pump and assures the supply to the H.P. pump. Position All the components are fitted on a bracket on the underside of the protection tube.

A connection between the two engines permits priming of one engine by the other. Priming can also be carried out using a hand pump.

Main components - Metal Filter (10 µ) - Min pressure switch - By-pass valve - Pressure transmitter (optional) - Manual valve - Ejector - Astatic valve - Pre-blockage indicator - Jet.



FUEL SYSTEM

ARRIEL 1

Training Manual

HP PUMP PRESSURE (FCU)

PRESSURE TRANSMITTER (optional)

BY-PASS VALVE

MIN PRESSURE SWITCH ASTATIC VALVE


BP FILTER

PRIMING SUPPLY TO OTHER ENGINE (version 1S)

HP PUMP PRESSURE (FCU)

EJECTOR

FILTER

FUEL SUCTION FROM TANK MANUAL VALVE

HP PUMP PRESSURE (FCU) TO HP PUMP (FCU)

FUEL SUCTION FROM TANK

EJECTOR

ASTATIC VALVE

MANUAL VALVE MIN PRESSURE SWITCH

BY-PASS VALVE

TO BP FILTER

FUEL SUCTION FROM TANK

JET

EJECTOR

LOW PRESSURE FUEL SYSTEM (1S, 1E VERSIONS)

FUEL SYSTEM - GENERAL (2) For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL SYSTEM - DESCRIPTION This part shows the main components of the fuel system.

Valves

Fuel pump

- Non-return valve

Gear type pump, mechanically driven by the accessory gearbox and fitted with a pressure relief valve.

- Pressurising valve

Filter

- Start injector electro-valve

The filter has a pre-blockage indicator (according to version) and a by-pass valve.

- Purge valve.

- Overspeed and drain valve

Injection system

Main and auxiliary valves

- Start injectors (2) The main and auxiliary valves are controlled by the control lever which acts at the same time on the acceleration control unit cam.

- Centrifugal injection wheel.

Metering device The hydromechanical controller acts on the metering needle (see next chapter).



FUEL SYSTEM

Training Manual PRE-BLOCKAGE INDICATOR

ARRIEL 1 START INJECTOR ELECTRO-VALVE

FUEL PUMP


START INJECTORS

FILTER FILTER BY-PASS VALVE

PURGE VALVE

AUXILIARY VALVE

MAIN VALVE

CONTROL LEVER

CAM METERING DEVICE


NON-RETURN VALVE INJECTION WHEEL

PRESSURISING VALVE

FUEL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL SYSTEM - OPERATION (1) This part deals with the following operating phases : prestart, starting, normal operation, manual control and shutdown.

Pre-start - The pump is not operating and there is no pressure in the system

Starting When engine start is selected, the start accessories are electrically supplied. The pump is driven and supplies the start injectors and then the centrifugal injection wheel.

- The main and auxiliary valves are closed

The constant ∆P valve operates and returns the excess fuel to the pump inlet.

- The constant ∆P valve is closed

The fuel flow is controlled by the movement of the control lever.

- The metering needle is closed by the acceleration control cam - The following valves are closed : • non return valve • pressurising valve • overspeed & drain valve • purge valve

At 45 % N1, the start accessories are de-energised by releasing the start button and the start injectors are ventilated by P2 air pressure. The control lever is moved to the flight position, progressively opening the main valve to accelerate the engine until the hydromechanical control takes over.

- The start injector electro-valve is closed.

Purge of the system During the initial phase of starting, the fuel supplied from the aircraft system flows into the F.C.U., through the nonreturn valve and to the purge valve which opens and returns the fuel to the tank. The purpose of this phase is to expel any air which may be in the system.



FUEL SYSTEM

Training Manual

ARRIEL 1

PRE-START - PURGE - STARTING

FUEL SYSTEM - OPERATION (1) For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL SYSTEM - OPERATION (2) Normal running

Manual control

The required fuel flow is metered by the metering needle. The metering needle position is determined by the hydromechanical control system (refer to "CONTROL SYSTEM" chapter).

The manual control is used for starting and stopping the engine. It can also be used in case of a control system failure.

The fuel pump always supplies more fuel than the engine requires. The excess fuel returns to the pump inlet through the constant ∆P valve. The start injectors are continuously ventilated by P2 air circulation.

Shut-down The lever is pulled fully rearward, closing the main valve which cuts the fuel flow to the engine causing it to run down & stop.



FUEL SYSTEM

Training Manual

ARRIEL 1

NORMAL RUNNING - SHUT-DOWN - MANUAL CONTROL

FUEL SYSTEM - OPERATION (2) For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL CONTROL UNIT - GENERAL Function

Main components

The Fuel Control Unit ensures fuel supply and fuel flow metering.

- Fuel pump - Filter

Position

- Pre-blockage indicator (according to version)

- On the left front face of the accessory gearbox.

- Valves and cam


- Metering unit.

- Type : hydro-mechanical - Mounting : clamp - Replaceable components : • Filter • Pre-blockage indicator (according to version).



FUEL SYSTEM

Training Manual

ARRIEL 1

VALVE SHAFT

CAM

MOUNTING CLAMP

PRE-BLOCKAGE INDICATOR (according to version)

FILTER (position according to version)

FUEL CONTROL UNIT - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL PUMP - GENERAL Function

Main components

The pump assembly supplies fuel under determined conditions of pressure and flow.

- Drive gear - Driven gear

Position

- Drive shaft

- In the FCU.

- Pressure relief valve.

Main characteristics - Spur gear type - Pressure relief valve setting : 3300 kPa (478.5 PSI) - Rotation speed : proportional to N1 speed.



FUEL SYSTEM

Training Manual

ARRIEL 1

DRIVEN GEAR

SHAFT

Type : Spur gear Pressure relief valve setting : 3300 kPa (478.5 PSI) DRIVE GEAR

Rotation speed : Proportional to N1 speed

FUEL PUMP - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL PUMP - DESCRIPTION - OPERATION Description

Operation

The assembly comprises the pressure pump and the pressure relief valve.

Fuel pump

Fuel pump

The pump receives fuel from the aircraft LP system. The fuel is drawn in by the pump, it passes between the gears and the casing and is forced out under pressure.

It is a spur gear type pump which has a drive gear and a driven gear, the drive gear being driven by the accessory drive via the pump drive shaft which is a quill shaft. Two lip seals, with a drain between them prevent fuel from entering the accessory gearbox.

Pressure relief valve

The pump is supplied with fuel from the aircraft system.

If the pump outlet pressure exceeds 3300 kPa (478.5 PSI) the pressure relief valve will open and allow fuel to return to the pump inlet thus limiting the maximum pressure in the system.

Pressure relief valve

Pressure reducing valve

It is a conical valve held closed by a spring.

The diaphragm is subjected to fuel pressure on one side opposed by spring pressure on the other side. The position of the diaphragm determines the position of the valve. When pump outlet pressure increases the diaphragm moves up, reducing the valve opening and thus maintaining a constant downstream pressure.

Pressure reducing valve This is a diaphragm valve which provides a constant pressure output of approx. 400 kPa (58 psi) for the hydraulic supply of the hydromechanical governor.



FUEL SYSTEM

ARRIEL 1

Training Manual


DRIVEN GEAR

FUEL PUMP

PUMP

PRESSURE REDUCING VALVE

DRIVE GEAR


DRAIN

SEALS

SHAFT

FUEL PUMP


FUEL PUMP - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL FILTER - GENERAL Function

Main components

The filter retains any particles that may be in the fuel in order to protect the metering unit components.

- Filter - Pre-blockage indicator (according to version)

Position

- By-pass valve.

- In the system : between the pump and the metering unit - On the engine : lower part of FCU.

Main characteristics - Type : metal cartridge - Filtering ability : 20 microns - By-pass valve setting : ∆P 200 kPa (39 PSID) - Pre-blockage pressure switch setting : ∆P 150 kPa (21.75 PSID).



FUEL SYSTEM

Training Manual

ARRIEL 1

PRE-BLOCKAGE INDICATOR (according to version) Type : Metal cartridge Filtering ability : 20 microns By-pass valve setting : ∆P 200 kPa (39 PSID) Pre-blockage pressure switch setting : ∆P 150 kPa (21.75 PSID)

FILTER AND BY-PASS VALVE (position according to version)

FUEL FILTER - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL FILTER - DESCRIPTION The assembly comprises the base, the filtering element, the by-pass valve and the pre-blockage indicator.

Filtering element It is a metal cartridge with a filtering ability of 20 microns. O'ring seals ensure the sealing between the cartridge and the filter housing.

Pre-blockage indicator This is a differential visual indicator. It includes a red indicator which pops out in a transparent cover when the pressure difference across the filtering element exceeds a given value. It comprises : - A body

By-pass valve

- A red indicator

This valve ensures a fuel flow to the metering unit in the event of filter blockage. It is subjected on one side to filter upstream pressure and on the other side to downstream pressure plus the force of a spring.

- Two O'ring seals which ensure the sealing between the indicator and the FCU body and between the upstream pressure inlet and the downstream pressure inlet.

Note : The pre-blockage indicator is not installed in all versions.



FUEL SYSTEM

ARRIEL 1

Training Manual

PIN

RED INDICATOR

CUP

TRANSPARENT COVER

O'RING SEAL BODY

FILTERING CARTRIDGE

BY-PASS VALVE

Upstream pressure

O'RING SEALS

FILTER BASE

Downstream pressure

FILTER


FUEL FILTER - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL FILTER - OPERATION The operation is considered in normal operation, preblockage and blockage.

Blockage When the pressure difference across the filtering element exceeds 200 kPa (39 PSID), the by-pass valve opens and causes the fuel flow to by-pass the filter.

Normal operation The fuel from the pump enters the fuel filter and flows through the filtering element (from outside to inside). The filtering element retains particles larger than 20 microns. The fuel then flows to the metering unit.

Pre-blockage When the filter becomes dirty, the pressure difference across the filtering element increases. If the pressure difference becomes higher than 150 kPa (21.75 PSID) the red visual indicator pops out.

Note : The pre-blockage indicator can be reset by removing the cover and pushing in the indicator.



FUEL SYSTEM

ARRIEL 1

Training Manual

FUEL FILTER

BY-PASS VALVE


NORMAL OPERATION FILTER BLOCKAGE ONSET

INDICATOR OPERATION : ∆P 150 kPa (21.75 PSID) (THE RED VISUAL INDICATOR APPEARS)

FILTER BLOCKAGE

PRE-BLOCKAGE

OPENING OF BY-PASS VALVE ∆P: 200 kPa (39 PSID)

BLOCKAGE

FUEL FILTER - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

MANUAL CONTROL - GENERAL Function

Main components

A mechanical control linked to the fuel control unit permits starting control, acceleration to nominal speed and stopping.

- Valve shaft - Cam control lever

It can also be used as a manual fuel flow control in the event of automatic control failure.

- Cam.

Position - Interface on the left side of the FCU.



FUEL SYSTEM

ARRIEL 1

Training Manual

VALVE SHAFT

CAM CONTROL LEVER

CAM

MANUAL CONTROL - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

MANUAL CONTROL - DESCRIPTION OPERATION Description

Operation

The manual control includes the following devices :

Stop position

- The main valve which permits acceleration control during the start phase and the use of the "emergency -" range

- position a : the two valves are closed, the cam maintains the metering needle closed.

- The auxiliary valve which is used for the "emergency + range"

Start and acceleration range

- The acceleration control cam which controls the position of the metering needle for starting.

- position b : progressive opening of the main valve ; the cam frees the metering needle above a certain angle. Flight position - position c : the main valve is fully open. "Emergency + range" - position d : progressive opening of the auxiliary valve, the main valve remaining open. "Emergency - range" In case of automatic control failure supplying too much fuel to the engine, the control lever can be placed in the start range to reduce the fuel flow.



FUEL SYSTEM

ARRIEL 1

Training Manual

MAIN VALVE

AUXILIARY VALVE

CONTROL LEVER c

b

62°

52°

5°

90 °

45°

a

d

P2

ACCELERATION CONTROL CAM

MANUAL CONTROL - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

METERING UNIT - GENERAL Function

Main components

It ensures constant metering of the fuel injected into the combustion chamber.

- Constant ∆P valve - Metering needle.

Position Note : See the "engine control" chapter for further description.

- In the system : downstream of the pump - On the engine : in the FCU.

Main characteristics - Profiled needle which moves in a calibrated orifice. - The metering needle is controlled by the hydromechanical control system.



FUEL SYSTEM

ARRIEL 1

Training Manual

CONSTANT ∆P VALVE

METERING NEEDLE (controlled by hydromechanical control system)

METERING UNIT - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

OVERSPEED AND DRAIN VALVE - GENERAL Function

Manual control system

The valve controls the fuel supply to the injection wheel :

- Pressurising valve

- Fuel supply during starting and in operation

- Overspeed and drain valve body

- Fuel shut-off and draining of the injection wheel during shut-down.

- Overspeed electro-valve.

The assembly also includes an electro-valve for a rapid engine shut-down in the event of power turbine overspeed (only on twin-engine aircraft).

Position - Lower left side of the combustion chamber casing.

Main characteristics Pressurising valve setting : 180 kPa (26.1 PSI).



FUEL SYSTEM

Training Manual

OVERSPEED AND DRAIN VALVE BODY

ARRIEL 1

PRESSURISING VALVE

OVERSPEED ELECTRO-VALVE (only on twin-engine version)

OVERSPEED AND DRAIN VALVE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

OVERSPEED AND DRAIN VALVE DESCRIPTION The assembly includes the pressurising valve, the dual valve and the overspeed electro-valve.

Pressurising valve This valve is operated by fuel pressure. Its main purpose is to ensure priority flow to the start injectors during the ignition phase.

Overspeed electro-valve Only on twin engine configuration. It drains the fuel under the diaphragm in case of N2 overspeed thus causing the dual valve to close and the engine to automatically shut down.

Dual valve It is actuated by a diaphragm subjected to fuel pressure : one valve to open and close the fuel passage to the injection wheel, the other one to drain the fuel remaining in the injection wheel.



FUEL SYSTEM

ARRIEL 1

Training Manual

PUMP PRESSURE

FUEL INLET

FUEL INLET

DUAL VALVE (ball valve)

FUEL OUTLET

PRESSURISING VALVE

DRAINING

DIAPHRAGM

OVERSPEED ELECTRO-VALVE (twin-engine)

FUEL OUTLET TO DUAL VALVE

PRESSURISING VALVE

DUAL VALVE (overspeed and drain valve)

OVERSPEED AND DRAIN VALVE - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

OVERSPEED AND DRAIN VALVE OPERATION Two operating positions can be considered : engine running (fuel supply) and engine stopped (fuel shut-off and draining of the wheel).

Engine running position As soon as the fuel pressure reaches the setting of the pressurising valve (180 kPa/26.10 PSI), the pressure is admitted under the diaphragm which causes the closing of the drain valve and the opening of the fuel supply valve. The fuel flows to the injection wheel and is sprayed into the combustion chamber.

Overspeed shut-down Engine shut-down can also be affected by the electrovalve which, when opened, causes the pressure to decrease below the diaphragm and the valve to move down (shutdown in case of power turbine overspeed for the engines provided with this safety system).

Note : The detail shows the dual valve position after complete shut-down of the engine.

Stop position The normal stop selection (closing of the main valve by the control lever) results in a decrease of injection pressure. The pressurising valve closes. The pressure decreases below the diaphragm and the dual valve moves down under pump pressure on the upper diaphragm. The drain valve opens (draining of fuel to prevent blockage of the injection manifold by carbonization of the remaining fuel). When the engine is completely stopped, the drain valve closes under the force of its spring.



FUEL SYSTEM

ARRIEL 1

Training Manual

DETAIL (after shut-down) Overspeed electro-valve

ENGINE RUNNING POSITION

DURING SHUT-DOWN

OVERSPEED AND DRAIN VALVE - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

START INJECTOR ELECTRO-VALVE GENERAL Function

Main components

The start injector electro-valve ensures the fuel distribution to the two injectors during engine starting.

- Start injector electro-valve - P2 ball valve

Position

- Re-injection prohibit switch

Upper part of the combustion chamber casing.

- Purge valve.

Main characteristics - Re-injection prohibit switch setting : ≈ 92 kPa (13.34 PSI) => 45 % N1 - Purge valve setting : • opening at 5 kPa (0.725 PSI) • closing at 120 kPa (17.4 PSI).



FUEL SYSTEM

ARRIEL 1

Training Manual

P2 BALL VALVE

START INJECTOR ELECTRO-VALVE AND REINJECTION PROHIBIT SWITCH

PURGE VALVE

PUMP PRESSURE PURGE TO TANK

P2

FUEL OUTLET TO INJECTORS

FUEL INLET

START INJECTOR ELECTRO-VALVE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

START INJECTOR ELECTRO-VALVE DESCRIPTION The assembly includes the electro-valve, the P2 ball valve, the reinjection prohibit switch and the purge valve.

Purge valve It ensures a pre-start purge by returning a certain quantity of fuel to the tank. As soon as start is selected, the pump pressure acts on the diaphragm to stop the purge. The auxiliary valve relieves the pressure under the diaphragm after the engine has stopped.

Electro-valve It opens when energised during starting.

P2 ball valve The valve admits P2 air pressure to ventilate the injectors after the starting phase.

Reinjection prohibit switch It prevents any electrical supply to the electro-valve when the P2 pressure reaches a certain value obtained at the end of starting and thus any reinjection.



FUEL SYSTEM

ARRIEL 1

Training Manual

RE-INJECTION PROHIBIT SWITCH

ELECTRO-VALVE

RETURN TO TANK

AUXILIARY VALVE

FUEL INLET

BALL VALVE

P2

PUMP PRESSURE

DIAPHRAGM AND VALVE


PURGE VALVE

START INJECTOR ELECTRO-VALVE - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

START INJECTOR ELECTRO-VALVE OPERATION Three main operating phases can be considered : purge before start, injection during start and ventilation in normal operation.

Purge of the system before starting During the initial phase of starting, the fuel supplied from the aircraft system flows into the F.C.U., through the nonreturn valve and to the purge valve which opens and returns the fuel to the tank. The purpose of this phase is to expel any air which may be in the system.

Ventilation of the injectors At the end of starting, the supply to the electro-valve is cut and the valve closes. The air under compressor pressure P2 (which has increased in the meantime) lifts the ball of the valve and flows to ventilate the injectors. This ventilation continues as long as the engine operates to prevent blockage of the injectors by carbonization of the remaining fuel. The P2 pressure actuates the pressure switch to prevent any reinjection which could cause a flame-out by suddenly reducing fuel flow to the injection wheel.

Fuel injection When starting is selected, the engine pump pressure increases rapidly and closes the purge valve, the electrovalve is energised open and the fuel supplied by the engine pump flows to the 2 injectors which spray it into the combustion chamber. The fuel is then ignited by the sparks of the igniter plugs.



FUEL SYSTEM

ARRIEL 1

Training Manual

PUMP PRESSURE

PURGING OF THE SYSTEM BEFORE STARTING

FUEL INJECTION

PUMP PRESSURE

VENTILATION OF THE INJECTORS

START INJECTOR ELECTRO-VALVE - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

MAIN INJECTION SYSTEM - GENERAL Function

Main components

The injection system sprays fuel into the combustion chamber to give stable and efficient combustion.

- Inlet union

Position

- Supply pipe - Distributor

- On the engine : inside the combustion chamber. The injection wheel is mounted between the centrifugal compressor and the turbine shaft. The distributor is bolted to the diffuser backplate.

- Wheel with spraying jets.

Main characteristics - Type : centrifugal injection - Radial fuel supply.



FUEL SYSTEM

Training Manual

ARRIEL 1

CENTRIFUGAL INJECTION WHEEL (with spraying jets) DISTRIBUTOR

Type : Centrifugal injection, radial fuel supply

FUEL INLET UNION

SUPPLY PIPE

MAIN INJECTION SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

MAIN INJECTION SYSTEM - DESCRIPTION OPERATION Description

Operation

The injection system comprises the fuel inlet union, the internal supply pipe and the centrifugal injection assemblydistributor and wheel.

The fuel is delivered to the distributor by the internal supply pipe. It passes through the distributor's axial holes into the chamber in the injection wheel.

Fuel inlet union Fitted at the lower right front face of the compressor casing, it has a plug to test the sealing of the union.

As the injection wheel is rotating at high speed (N1) the fuel is centrifuged out through the radial holes and is sprayed between the two swirl plates.

Internal supply pipe

It should be noted that the injection pressure is supplied by the centrifugal force and therefore the fuel system does not require very high pressures.

This pipe connects the inlet union to the fuel distributor. It is fitted between the front swirl plate and the diffuser backplate.

Centrifugal injection assembly

The injection wheel fuel chamber is sealed by pressurised labyrinth seals. There is a small air flow into the fuel chamber. During shut-down the fuel remaining in the system is purged via the overspeed and drain valve.

This assembly consists of a stationary distributor and a wheel. The distributor, fitted onto the diffuser back-plate, is drilled with axial holes which deliver the fuel to the wheel. The injection wheel, mounted by curvic couplings between the compressor and the turbine shaft, is drilled with radial holes which form the fuel spraying jets. Sealing between the distributor and the wheel is achieved by pressurised labyrinth seals.



FUEL SYSTEM

ARRIEL 1

Training Manual

FUEL SPRAYING INTO THE COMBUSTION CHAMBER

CENTRIFUGAL WHEEL

DISTRIBUTOR

FUEL INLET UNION

INTERNAL SUPPLY PIPE

FUEL INLET LEAK CHECK PLUG

MAIN INJECTION SYSTEM - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

START INJECTORS - GENERAL Function

Main components

The two start injectors spray fuel into the combustion chamber during engine starting.

- Mounting flange - Fuel inlet union

Position

- Injector body

- On the upper part of the turbine casing at 2 o'clock and 10 o'clock

- Spraying jet.

- They penetrate into the mixer unit.

Main characteristics - Type : simple injector - Quantity : 2 - Ventilation : by air flow.



FUEL SYSTEM

ARRIEL 1

Training Manual

INJECTOR IGNITER PLUG

Type : Simple injector Quantity : 2 Ventilation : By air flow

START INJECTORS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

START INJECTORS - DESCRIPTION OPERATION Description

Operation

The injectors are mounted on the upper part of the turbine casing. They penetrate into the combustion chamber through holes in the mixer unit.

Starting

They are secured by two bolts onto bosses with seals and spacers to prevent leaks and adjust the depth of penetration into the combustion chamber.

The fuel is atomised and is ignited by the sparks from the igniter plugs. The flame thus produced, ignites the fuel sprayed by the centrifugal injection wheel.

Injector components

Normal running

- Injector body with mounting flange

When the engine reaches self sustaining speed (approx. 45 % N1) the fuel supply to the injectors is shut off.

- Fuel inlet (threaded to receive a union) - Filter manifold - Spacer and seals - Nut

During starting the injectors are supplied with fuel.

P2 air is then blown through the injectors to avoid carbonisation of the residual fuel. It should be noted that ventilation is continuous during engine running.

- Jet - Shroud.



FUEL SYSTEM

ARRIEL 1

Training Manual

INJECTOR

START INJECTOR SUPPLY

FUEL INLET MOUNTING FLANGE (mounting with two bolts)

Starting SPACERS AND SEALS

FILTER MANIFOLD

START INJECTOR VENTILATION

SHROUD JET

P2

NUT

Normal running

DESCRIPTION

OPERATION

START INJECTORS - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

COMBUSTION CHAMBER DRAIN VALVE GENERAL Function

Main components

The valve drains overboard any unburnt fuel remaining in the combustion chamber.

- Valve body - Outlet union.

Position - On the engine : screwed into the turbine casing lower part.

Main characteristics - Type : half-ball valve - Setting : Closing obtained at about 40 % N1.



FUEL SYSTEM

Training Manual

ARRIEL 1

VALVE BODY Type : Half-ball valve Setting : Closing obtained at about ≈ 40 % N1

OUTLET UNION

COMBUSTION CHAMBER DRAIN VALVE - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

COMBUSTION CHAMBER DRAIN VALVE DESCRIPTION - OPERATION Description

Operation

The drain valve includes the following components :

The valve has two positions : open and closed.

- A threaded part to fix the valve on the combustion chamber

Open position

- A half ball valve mounted on a tension spring

When the engine is not running and at the beginning of start, the valve is held open by the action of the tension spring.

- An outlet union which connects to the drain system - A circlip which retains the valve in the body.

Any unburnt fuel in the combustion chamber will drain through the valve overboard to the drain system. This ensures that no fuel accumulates in the combustion chamber which could cause starting problems (e.g. : overtemperature) . Closed position As the engine starts the combustion chamber pressure increases. This pressure is felt on the upper surface of the half ball which moves down to close the drain. The valve closes during the initial phase of starting for a speed of about 40 % N1.



FUEL SYSTEM

ARRIEL 1

Training Manual

Unburnt fuel

CIRCLIP

P2 air pressure

THREADS

SEAL

SPRING

To drain system HALF-BALL VALVE

OUTLET UNION

"OPEN" position

DESCRIPTION

"CLOSED" position

OPERATION

COMBUSTION CHAMBER DRAIN VALVE - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

Training Manual

ARRIEL 1

FUEL PIPES Description

Note : The pipes may be different according to version.

The fuel pipes ensure the circulation of fuel between the components of the system.

Main characteristics - Type : rigid, stainless steel - Unions : with integral olives.

Main pipes - Fuel inlet union - From FCU to overspeed and drain valve and to injector electro-valve - From electro-valve to the two injectors - From overspeed and drain valve to fuel inlet union - From union to the wheel (internal pipe) - From the pump to the overspeed and drain valve and the purge valve (control system) - Drains.



FUEL SYSTEM

ARRIEL 1

Training Manual

FCU TO OVERSPEED AND DRAIN VALVE AND TO START INJECTOR ELECTRO-VALVE

PUMP PRESSURE TO OVERSPEED AND DRAIN VALVE AND PURGE VALVE

RETURN TO TANK

ELECTRO-VALVE TO INJECTORS

P2 P2

FUEL INLET UNION

DRAINS

OVERSPEED AND DRAIN VALVE TO FUEL INLET UNION

FUEL PIPES For training purposes only © Copyright - TURBOMECA - 2000


FUEL SYSTEM

ARRIEL 1

Training Manual

7 - CONTROL SYSTEM - Control system ............................................................... 7.2 • General ...................................................................... 7.2 • Description .................................................................................. 7.4 • Operation ................................................................... 7.6 à 7.33



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - GENERAL Functions

Main components

The system is designed to adapt the engine to the aircraft power requirements whilst remaining within defined limits.

- Fuel control unit - Engine and systems

The main functions are : - Aircraft : various systems (control, indication, supply) - Manual control - Tachometer box - according to version. - Speed control - Various limits - Acceleration control - Overspeed protection.

Main characteristics - Hydromechanical control - Manual control.



CONTROL SYSTEM

ARRIEL 1

Training Manual

CONOCO

G-BKXD SA 365 N

Management Aviation

AIRCRAFT (various systems)

TEST

F.C.U.

MAIN FUNCTIONS

TACHOMETER BOX (according to version)

- Manual control - Speed control - Various limits - Acceleration control - Overspeed protection

ENGINE (engine and systems)

CONTROL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - DESCRIPTION The complete system includes aircraft components, engine components and the FCU.

Aircraft components - Control devices (control lever and anticipator)

- FCU components : • Power turbine speed governor • Gas generator speed governor • Acceleration control unit • Metering unit.

- Indicating devices (indicators, lights...)

Engine components - Hydromechanical components : • Overspeed and drain valve • Purge valve • Start injector electro-valve • Pressurising valve • Start injectors • Main injection system



CONTROL SYSTEM

ARRIEL 1

Training Manual


ANTICIPATOR

START INJECTORS

POWER TURBINE SPEED GOVERNOR

PURGE VALVE CONTROL LEVER

GAS GENERATOR SPEED GOVERNOR


ACCELERATION CONTROL UNIT

METERING UNIT

PRESSURIZING VALVE

INJECTION WHEEL

CONTROL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (1) Control - General

Adaptation to requirements

Installation configuration

The control system ensures the engine adaptation to the requirements by metering the fuel flow CH sprayed into the combustion chamber.

The gas generator supplies power to the power turbine which is connected to the helicopter main rotor. Installation requirements - Aircraft rotor speed (NR) almost constant in all operating conditions (because of the rotor efficiency) whatever the load applied - Max torque limitation (imposed by the mechanical transmission and the helicopter main gearbox) - Power turbine rotation speed (N2) within given limits (in fact almost constant, as it is connected to the rotor)

Thus, the gas generator adapts automatically to the requirements (N1 demand) to maintain constant power turbine rotation speed N2 whilst keeping all the other parameters within determined limits. This adaptation is illustrated by : - The diagram W/N2 which illustrates the power W, the max torque C and the rotation speeds N1 and N2 - The diagram N1/N2 which illustrates the N1/N2 relationship.

- Limitation of the gas generator rotation speed N1 : • Max N1 (maximum engine power) • Min N1 (to avoid critical speeds) - Load sharing (equal sharing of loads between the 2 engines) - Protection against surge, flame-out, overtemp…



CONTROL SYSTEM

ARRIEL 1

Training Manual NR W

N2

N1

x

Ma

W

Max N1

e qu tor

N1 isospeeds

C

TET Min N1

CH

N2

Control system

POWER W / N1, N2 REQUIREMENTS

N1

- NR - N2 - Max torque - N1 - W eng 1 = W eng 2 - Protections

Max Nominal N2

Operating range Min

INSTALLATION CONFIGURATION AND REQUIREMENTS N1 / N2

N2

ADAPTATION TO REQUIREMENTS

CONTROL - GENERAL

CONTROL SYSTEM - OPERATION (1) For training purposes only © Copyright - TURBOMECA - 2000


CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (2) Principle of the control loop

Static droop

The system meters the fuel flow in order to match the engine power to the requirements thus keeping power turbine rotation speed constant. The control components are contained in the hydromechanical unit mounted on the front face of the accessory gearbox.

In this type of control, the speed N1 is made inversely proportional to N2. The relation N1/N2 illustrates this proportionality and the N2 variation is called "static droop".

Operation of the control loop The power turbine governor compares the actual speed N2 with a speed datum which varies with the collective pitch. It determines a speed datum (N1*) which is a function of the difference measured.

This droop ensures the stability of the system but it cannot be tolerated as the helicopter rotor requires a given speed. As the load mainly results from the collective pitch, a linkage with the governor is provided to compensate the static droop. Moreover, this linkage advances the phase of detection (this is why it is called anticipator) to reduce the response time.

The gas generator governor compares the datum speed (N1*) and the actual speed (N1) and meters the fuel to maintain the datum speed, thus matching the gas generator to the conditions.

The diagram illustrates the static droop line for different collective pitch angles (anticipator effect).

The acceleration control unit limits the transient fuel flow variations in relation to P2 pressure so as to prevent compressor surge while permitting quick response times.

In operation, the points 1, 2 and 3 are obtained and the droop is slighthy overcompensated ; ie : power turbine speed (and therefore rotor speed) maintained almost constant in all operating conditions.

In the diagram : θ1 = low pitch, θ2 = medium pitch, θ3 = high pitch.

In transient conditions, the power turbine speed varies, but the governing system responds to regain the nominal speed very quickly. Note : the static droop is slightly overcompensated.



CONTROL SYSTEM

ARRIEL 1

Training Manual N1 POWER TURBINE

GAS GENERATOR

N2

N1

N2

N1

WITHOUT ANTICIPATOR

MAIN GEARBOX

P2

Static droop

Q

COLLECTIVE PITCH CONTROL θ


N1

+

Static droop line without anticipator for different θ θ3

N1

GAS GENERATOR SPEED GOVERNOR

N2

θ2

WITH ANTICIPATOR

θ1

N1* +

3

Apparent static droop line

N2

POWER TURBINE SPEED GOVERNOR

2 +

N2*

1

Apparent static droop

N2

PRINCIPLE OF THE CONTROL LOOP



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (3) Hydraulics of the FCU The hydromechanical control unit operates with the fuel as hydraulic fluid and lubricant. The illustration shows the entire fuel system.



CONTROL SYSTEM

Training Manual

ARRIEL 1

HYDRAULICS OF THE FCU



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (4) Power turbine governor

Operating envelope of control

This proportional type governor determines a datum signal according to the anticipator signal and the actual speed.

The graph illustrates the N2 speed between max and min N1 ; the static droop is compensated, and slightly overcompensated, by the action of the anticipator.

In stabilized conditions, the flyweight centrifugal force balances the datum spring force. The articulated lever is in a fixed position in front of the potentiometric jet. The reduced pressure flows to the low pressure and a modulated pressure is established in the chamber. The amplifier piston (subjected to a reference pressure on one side and to the modulated pressure on the other side) determines the N1 datum transmitted to the gas generator governor by a lever and a plunger. Transient conditions, the anticipator modifies the spring tension while the centrifugal force changes. The articulated lever pivots and moves in front of the potentiometric jet thus altering the leak and therefore changing the modulated pressure. The amplifier piston then moves and, by means of the lever and plunger, sets a new datum on the gas generator governor. The gas generator adapts itself to the new condition until the balance is regained.



CONTROL SYSTEM

ARRIEL 1

Training Manual

ANTICIPATOR

N2 DATUM SPRING

N2 SPEED DETECTOR (flyweight)

N1 Max 100% Power turbine nominal speed 90 Static droop lines for different collective pitch positions 80

MAX N1 STOP

ARTICULATED LEVER

POTENTIOMETRIC JET

70 Min

MIN N1 STOP

100% N1 DATUM PLUNGER

Low pressure (≈ 1 b)

AMPLIFIER PISTON

Modulated pressure N2 (≈ 2.8 b)

N2

Operating envelope of control

Reduced pressure (≈ 4 b)

POWER TURBINE GOVERNOR



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (5) Gas generator governor This integral type governor controls the datum speed demanded by the power turbine governor. It achieves this control by metering the fuel flow. In stabilized conditions, the flyweight centrifugal force balances the force of the datum spring. The lever is in a fixed position and the valve determines a given modulated pressure. The working piston controls a given position of the metering needle which meters the fuel flow to obtain the required rotation speed. The system is "in balance". In transient conditions, we have seen that the power turbine governor determines a new datum which upsets the balance. The lever moves, the leak varies and consequently the modulated pressure. The working piston moves the metering needle until the new N1 datum is obtained. The gas generator speed increases or decreases, thus regulating engine output power to match the load and obtain a constant power turbine speed.



CONTROL SYSTEM

ARRIEL 1

Training Manual

C LOAD C (Eg : collective pitch) N1 DATUM SPRING

ARTICULATED LEVER

N1 SPEED DETECTOR (flyweight)

t N2 N2 SPEED (Transient variation and quick return to nominal speed)

DAMPING DEVICE

t

Q FUEL FLOW Q (Variation controlled by the governor) t

N1 POTENTIOMETRIC JET

WORKING PISTON

METERING NEEDLE

N1 SPEED (Increase or decrease to match the load variations)

THERMAL COMPENSATOR Low pressure (≈ 1 b)

Modulated pressure N1 (≈ 3 b)

Reduced pressure (≈ 4 b)

t VARIATION OF THE MAIN PARAMETERS IN TIME

GAS GENERATOR GOVERNOR



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (6) Acceleration control unit It limits fuel flow increase in transient conditions, in order to prevent compressor surge during acceleration. In stabilized conditions, there is a gap between the fork and the metering valve. The position of the metering valve is determined by the working piston. In load increase transient conditions, the governor "responds" and the working piston moves rapidly. Under the action of its spring, the metering needle opens until it stops against the fork. This displacement represents what is called "instant flow increase" initiating the acceleration. Then the subsequent increase in P2 pressure causes the deformation of the capsule which permits further opening of the metering needle until it comes into contact with the working piston.



CONTROL SYSTEM

ARRIEL 1

Training Manual

Q

Max flow for a determined P2 pressure (lever mechanism position) Max flow stop of the acceleration control unit

Maxi X WORKING PISTON

CAM

"X" instant flow increase = distance between the metering valve position and fork position Min flow stop of the acceleration control unit

Mini

P0 ACCELERATION CAPSULE

P2 ACCELERATION CURVE (Fuel flow Q as a function of compressor pressure P2) WORKING PISTON

GAP (x)

CAM

FUEL METERING NEEDLE

x

P0

P2

BAROSTATIC DEVICE

METERING NEEDLE

ACCELERATION CAPSULE

LEVER MECHANISM LEVER MECHANISM DIAGRAM OF THE MECHANISM




CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (7) Deceleration control unit In some versions, a deceleration control unit (or min flow limiter) is included in the metering unit to prevent flameout during deceleration. In load decrease transient conditions, the closing of the metering needle is limited by a mechanical stop. This mechanical stop is controlled by a diaphragm subjected to P2 pressure. The stop withdraws as the P2 pressure decreases in order to prevent engine flame-out during rapid deceleration.



CONTROL SYSTEM

ARRIEL 1

Training Manual

DECELERATION CONTROL UNIT

Q P2 P0

Min flow curve as a function of P2 pressure

P2 DECELERATION CURVE (Q as a function of P2)

P2

DECELERATION CONTROL UNIT



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (8) Metering unit

The graphs below illustrate the valve operation

Metering needle

Graph of fuel flow (Q) as a function of metering needle position (S) : each position corresponds to a fuel flow and each displacement ∆S corresponds to a proportional flow variation ∆Q.

The metering needle is a profiled needle which moves in a calibrated orifice. The fuel under pump pressure flows through the passage determined by the metering needle sliding in the orifice. Constant ∆P valve

Graph of fuel flow (Q) in relation to the pressure difference (∆P) : in transient conditions, the ∆P varies, but the valve operates to return it to its initial value with a slight static droop.

To obtain a fuel flow solely depending upon the metering needle position, this valve keeps a constant pressure difference across the metering needle. It consists of a diaphragm subjected metering needle pressure variation. Any variation of pressure difference (∆P) is sensed by this valve which returns more or less fuel to the inlet of the pump. In fact, the pump always supplies a flow higher than the engine requirements and the excess fuel is returned to the inlet. The ∆P transient variations are due to the pump pressure variations, to the downstream pressure variations and of course to the displacement of the metering valve. For example : when the metering needle opens, the pressure difference decreases, the valve diaphragm senses this and moves to close the return. More fuel is admitted to the engine, the upstream pressure increases and the nominal ∆P is regained.



CONTROL SYSTEM

ARRIEL 1

Training Manual

FUEL RETURN

FUEL INLET

CONSTANT ∆P VALVE

Q

Q

Max

Min

∆Q

∆P Q AS A FUNCTION OF ∆P

METERING NEEDLE

∆S

S

Q AS A FUNCTION OF NEEDLE POSITIONS (S)

FUEL OUTLET

METERING UNIT



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (9) Limits of gas generator speeds

Min governed speed

The gas generator rotation speed varies (to adapt the engine to changing conditions) between two extreme limits represented by adjustable mechanical stops.

It is limited by a fixed adjustable mechanical stop to avoid low speeds corresponding to critical ratings. In operation, this limit is practically never reached because, even at zero torque, the power to drive the compressor requires a higher speed. Therefore, the stop is only a safety measure and it is only adjusted on the FCU test rig.

Max speed It is automatically limited by a fixed adjustable stop which represents the max operating rating.

Limits of fuel flow

TAKE-OFF - Max take-off power in the case of a single engine (in fact, this rating is given at a value slightly lower than the mechanical stop and the engine must be operated not to overcome it).

Fuel flow variation in transient conditions is limited by the acceleration control unit to obtain an optimum acceleration without compressor surge. The acceleration rate determines the response time. The slope of acceleration is only adjustable on the test rig.

MAX CONTINGENCY - Max power in the case of engine failure during takeoff or landing of a twin engine helicopter. In some versions an extreme rating called super contingency power is used.

The min fuel flow (limit to prevent flame-out) is limited by a mechanical stop on the metering needle. In some versions, this stop is variable with P2 pressure ; it is also called the deceleration control unit.

The effect of fuel temperature on the speed (variation of fuel viscosity changing the balance point of the hydromechanical governor) is compensated by the capsule in order to obtain speed invariability (especially max N1). A slight max N1 variation is however introduced but within given limits.


The max fuel flow is determined by the full opening of the metering needle for a given pressure difference ∆P. It is a factory adjustment which represents a sort of power limitation. In manual control (emergency control), the max fuel flow is limited at a lower value to avoid exceeding of the limits.


CONTROL SYSTEM

ARRIEL 1

Training Manual

N1 Max. 100%

90

80

70

Min. Q 100%

N1

N1 thermal limit

N2

Metering unit max Q

Manual control max Q (emergency)

N1 max as a function of fuel temperature

Metering unit min Q (with deceleration control unit)

N1limit to ensure power

Metering unit min Q (without deceleration control unit) t°

P2

N1 LIMITS

FUEL FLOW LIMITS (Q)

LIMITS



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (10) Limit of torque

Power turbine overspeed safety system

A max torque limit is required by the mechanical transmission. The control system does not ensure a torque limit and the operating instructions should be observed to prevent any overtorque. The flight manual indicates the torque limits : also see chapter "indication" of this manual for details of the torque measuring system.

This safety system is not included in the control unit but is often mentioned among the functions of the engine control system. The overspeed safety system is designed mainly to take into account the case of shaft failure resulting in a very sudden acceleration which cannot be contained by the speed governor. The system includes a speed detector, an electronic unit and the overspeed and drain valve of the fuel system. It is installed on some versions : twin engine configurations mainly (see details of the system in electric system chapter).



CONTROL SYSTEM

ARRIEL 1

Training Manual


TACHOMETER BOX

N2 DETECTOR

Q

C TEST

TORQUE INDICATOR

LIMIT OF TORQUE - POWER TURBINE OVERSPEED SAFETY SYSTEM



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (11) Control system performance

Dynamic variation of power turbine speed

As regards the operation, the control system performance determines some flight characteristics.

It is the transient speed variation occurring during a load variation. The amplitude of this variation can be observed on the rotor speed indicator ; it is related to the other characteristics.

The following can be distinguished : - The response time

Static variation of power turbine speed

- The static and dynamic power turbine speed variations - The max speed of the gas generator.

Response time It can be defined as the time required to regain power turbine nominal speed in transient conditions. The response time is closely associated to the rate of acceleration of the gas generator. A check of the response time can be made by recording parameters during a load application. It is approx. 4 seconds between N1 min and max in standard conditions.


It can be defined as the speed variation at different ratings. This static variation (a static droop which is slightly overcompensated) can be checked by noting NR speed at different operating points (eg : ground fine pitch and cruise pitch). With the increase of power, the NR increases slightly within given limits.

Max available speed of the gas generator It is the max speed that can be obtained from the gas generator (take-off on single engine and max contingency on twin engine). This rating can be checked on a load application, noting the max speed obtained when the rotor speed starts decreasing.


CONTROL SYSTEM

ARRIEL 1

Training Manual

N2

N1

Max

100% ≈ 4 sec 90

80 Time

≈ 4 sec

70

Min

100% RESPONSE TIME AND DYNAMIC VARIATION OF THE POWER TURBINE SPEED N2

N2

STATIC VARIATION OF N2 POWER TURBINE SPEED

CONTROL SYSTEM PERFORMANCE



CONTROL SYSTEM

Training Manual

ARRIEL 1

CONTROL SYSTEM - OPERATION (12) Twin-engine configuration Principle of load sharing In normal conditions, the helicopter rotor is driven by the two power turbines and therefore : NR = k N2 eng 1 = k N2 eng 2 The speed signals received by the two power turbine governors being identical (as well as the signals from the collective pitch), they determine identical datum signals sent to the two gas generator governors which meter fuel flow to keep them constant. As the power is closely related to the N1 speed and as the efficiency does not vary much from one power turbine to another, a fairly good load sharing is obtained. Operation on one engine In this case, the engine remaining in operation supplies the power while the other one is disconnected by the free wheel. The limit of the operative engine is represented by the max contingency rating automatically limited by the fuel control unit. This rating, determined for engine failure during take-off or landing, has a limited duration : 2 mn 30 s.



CONTROL SYSTEM

ARRIEL 1

Training Manual

MAIN GEARBOX

NR=k.N2 eng1=k.N2 eng2

COLLECTIVE PITCH

NR N2 (1&2)

N

Tq1&Tq2

FREE WHEEL REDUCTION GEARBOX

C

POWER TURBINE GAS GENERATOR N2

t4 t4

Q

POWER TURBINE GOVERNOR

N1 Max N1

N1 TRIM N2*

N1* GAS GENERATOR GOVERNOR

TWIN-ENGINE CONFIGURATION



CONTROL SYSTEM

ARRIEL 1

Training Manual

CONTROL SYSTEM - OPERATION (13) Control system loop (1)

Evolution of parameters

"Image" of load increase

θ

t = 0 - "Start" Collective pitch movement θ

-

The pitch increases

W1 > W

-

The resisting torque becomes higher than the drive torque

N2

-

The power turbine rotation speed decreases

G

-

The N2 governor detects the 2 signals, and sends a datum increase to the N1 governor : the N1 governor increases the fuel flow Q

Q

-

Instantaneous flow step

P2

-

The compressor discharge pressure increases

AC

-

The acceleration control unit enables the acceleration to continue

- Collective pitch Sudden increase from min. to max. almost instantly

N2 - Power turbine speed Transient decrease and rapid return to nominal speed after a slight overshoot, and a slight overcompensation of the static droop N1 - Gas generator speed Speed increase and stabilisation after a slight overshoot t

- Time in seconds

Combustion - The flow Q increases in the combustion chamber N1 - increases, the output power W increases, the N2 speed stops decreasing and returns to its nominal value when the equilibrium between torques W1 = W is achieved. t = 4 seconds End of transient



CONTROL SYSTEM

ARRIEL 1

Training Manual

NR

t=0 t t=4 N2

1 W >W

N2

3

1 W=W

1

N2

2 t

N2

G

N1 2

W

Q

N1

P2

3

1 t 1

3

AC

2

3

2

Combustion Q 1 "Image" of a load increase

N1

N2

Evolution of parameters during a load increase

CONTROL SYSTEM LOOP (1)



CONTROL SYSTEM

ARRIEL 1

Training Manual

CONTROL SYSTEM - OPERATION (14) Control system loop (2)

Evolution of parameters

"Image" of a load decrease

θ

t = 0 - "Start" Collective pitch movement

- Collective pitch Rapid decrease of pitch

N2 - Power turbine speed Transient increase and return to nominal speed (within the static droop)

θ

-

The pitch decreases

W1 < W

-

The resisting torque becomes lower than the drive torque

N2

-

The power turbine rotation speed increases

N1 - Gas generator speed Speed decrease and stabilisation

G

-

The governor detects the N2 increase and decreases the fuel flow Q

t

DC

-

The deceleration controller limits the min fuel flow (if needs be)

- Time in seconds

Combustion - The flow Q decreases in the combustion chamber N1 - decreases, the output power W decreases, the N2 speed returns to its nominal value. t = 4 seconds End of transient



CONTROL SYSTEM

ARRIEL 1

Training Manual

NR

t=0 t t=4

N2

1 W
N2

2 1 3

1 W =W

N2 t N1

G

N2

1 Q

W

3 N1

P2

2 1

DC

t 1 3

2

Combustion Q

N1

3

N2

2 "Image" of a load decrease

Evolution of parameters during a load decrease

CONTROL SYSTEM LOOP (2)



CONTROL SYSTEM

ARRIEL 1

Training Manual

8 - CONTROL AND INDICATION - Manual control system .................................................. - Indicating system ........................................................... - Speed indication............................................................. - Tachometer transmitters............................................... - Speed probes (1K, 1S, 1E versions).............................. - Gas temperature indication .......................................... - Thermocouple probes.................................................... - Thermocouple junction box (1S version) .................... - Torque indication........................................................... - Torquemeter ................................................................... - Torque transmitter ........................................................ - Miscellaneous indications .............................................


8.2 8.6 8.8 8.10 8.14 8.16 8.18 8.20 8.22 8.24 8.26 8.28 to 8.35


CONTROL AND INDICATION

Training Manual

ARRIEL 1

MANUAL CONTROL SYSTEM - GENERAL Function The system ensures the manual control of the engine.

Main components Fuel flow control This lever is used to start and stop the engine and to control the engine power manually in the event of an FCU failure. Anticipator control This lever links the collective pitch to the fuel control unit.

Note : As regards the electrical controls refer to chapters starting and electrical.




ARRIEL 1

Training Manual

FUEL FLOW CONTROL

CONTROL LEVER

ELECTRICAL CONTROLS

COLLECTIVE PITCH

ANTICIPATOR CONTROL FCU

MANUAL CONTROL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

MANUAL CONTROL SYSTEM - MECHANICAL CONTROLS Function

Stop position. Cam in contact, the two valves are closed.

The control lever is used to control engine start and shutdown. It can also be used for manual engine power control ; particularly in the event of a failure of the control system.

Start position. Lever at approx 20°, slight opening of the main valve.

The collective pitch lever inputs signals to the anticipator during flight.

Acceleration range. Lever moved from "idle" position to "flight" position ; progressive opening of the main valve, and after a certain angle the cam releases its contact.

Description

Flight position. Lever in the "flight" notch : main valve fully open.

This system includes the control lever with its mechanical linkage and the collective pitch lever with its mechanical linkage.

Manual range (+). After overriding the lock, the lever can be moved forward in the + range : increase of fuel flow.

Operation

Manual range (-). Lever moved rearward in the (-) range : decrease of fuel flow down to shut-down after overriding the lock.

This part only mentions the position of the mechanical control lever. See chapter 6 and the aircraft manual for more details.




ARRIEL 1

Training Manual

90° 52°

45°

5°

CONTROL LEVER FUEL CONTROL UNIT

0° COLLECTIVE PITCH

HELICOPTER

0°

11

ENGINE

MANUAL CONTROL SYSTEM - MECHANICAL CONTROLS For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

INDICATING SYSTEM Functions

Miscellaneous indications

The indicating system provides the following functions :

- N1 gas generator rotation speed

- It allows the pilot to check that the engine is operating within determined limits

- N2 power turbine rotation speed - t4 gas temperature

- It indicates faults or abnormal changes of parameters - Engine torque - It allows the checking of certain operating phases. - Oil system (refer to Chapter "OIL SYSTEM") Note : In fact there are operating parameters (e.g. : N1 and torque) and monitoring parameters (e.g. N2, t4, oil temperature and pressure).


- Indicating lights - Cycle counter.



ARRIEL 1

Training Manual

FUNCTIONS - To ensure that the engine operates within determined limits

N1 SPEED INDICATION

t4 TEMPERATURE INDICATION

- To indicate fault or abnormal changes of parameters - To check certain operating phases

MISCELLANEOUS INDICATIONS

LUBRICATING SYSTEM INDICATION N2 SPEED INDICATION

ENGINE TORQUE INDICATION

INDICATING SYSTEM For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

SPEED INDICATION Function

Operation

This system measures the rotation speeds of the gas generator (N1) and the power turbine (N2).

N1 is an operating parameter as it reflects the engine power and serves to determine the limit ratings.


The N2 signal is used for the N2 indication (associated with the NR indication).

- Type : tachometer transmitter or phonic wheel according to version - Transmitter signals : frequency proportional to the rotation speed.

Main components - N1 speed transmitter - N2 speed transmitter - Electrical harnesses for connection to the indicators.

Description One or two tachometer generators (N2 optional) linked to one or two indicators.




Training Manual

ARRIEL 1

N1 INDICATOR

N2 INDICATOR

ACCESSORY GEARBOX REAR FACE

SPEED INDICATION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

TACHOMETER TRANSMITTERS GENERAL Function

Main components

To measure the rotating assembly's rotation speed.

- Body

Position

- Electrical plug.

- Rear face of the accessory gearbox : • N1 on the right side • N2 on the left side according to version.

Main characteristics - Quantity : 2 identical N1 and N2 transmitters (interchangeable) - Type : 3-phase permanent magnet generator.




ARRIEL 1

Training Manual

BODY

Number : 2 identical transmitters Type : 3 phase, permanent magnet generator

ELECTRICAL PLUG

TACHOMETER TRANSMITTERS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

N1 & N2 TACHOMETER TRANSMITTERS DESCRIPTION - OPERATION Description

Operation N2

The assembly consists of :

The permanent magnet rotation in front of the three coils induces an alternating current.

- A tachometer generator which has a mechanically driven permanent magnet as rotor. It delivers an electrical signal which is a three-phase alternating current with a frequency proportional to the speed

The frequency of this current is proportional to the rotation speed.

- An asynchronous motor which receives the transmitter signal and displays the speed on a graduated dial.

In normal operation, there is a link between the rotor speed NR and the power turbine speed N2. The same instrument can be used to indicate the NR and N2 speeds (the two N2 speeds in a twin engine configuration).

Operation N1 The permanent magnet rotation in front of the three coils induces an alternating current. The frequency of this current is proportional to the rotation speed.




ARRIEL 1

Training Manual

INDICATOR

STATOR

N1 & N2 TACHOMETER TRANSMITTERS - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

SPEED PROBES (1K, 1S, 1E VERSIONS) Description - Operation

Operation

On the versions 1E, 1K and 1S the speed indication is achieved using phonic wheels and speed probes.

The passage of the teeth in front of the electro-magnetic probe induces an alternating current in the probe windings. This current has a frequency proportional to the speed and the number of teeth :

Description

nd x N

The system consists of a toothed wheel, called a phonic wheel, rotating in front of an electro-magnetic pick-up which is connected to an indicator. The phonic wheel for N1 indication is fitted on the starter generator drive shaft. The N1 probe is mounted on the accessory gearbox casing right hand side. The phonic wheel for N2 indication is fitted on the rear of the intermediate gear of the reduction gearbox and the N2 probe is mounted in the bottom of the rear drive shaft casing.


F= 60 Where : nd = N° of teeth ; N = rotation speed in RPM ; F = frequency The signal from the probe is transmitted to the cockpit indicator which transforms it into an indication which may be analog, digital or both.



ARRIEL 1

Training Manual

TO THE INDICATOR

N1 SPEED PROBE


N1 SPEED PROBE

REAR OF THE INTERMEDIATE GEAR OF THE REDUCTION GEARBOX

PHONIC WHEEL

PHONIC WHEEL (starter generator drive shaft) F=

SPEED PROBE

nd x N 60

N2 SPEED PROBE ELECTRICAL CONNECTOR INDICATOR

ELECTRO-MAGNETIC PROBE

PHONIC WHEEL

N2 SPEED PROBE

DESCRIPTION

OPERATION

SPEED PROBES (1K, 1S, 1E VERSIONS) For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

GAS TEMPERATURE INDICATION

THERMOCOUPLE PROBES FUNCTIONAL DESCRIPTION

Function This system provides an indication of the gas temperature (t4) at the gas generator turbine outlet.


Position

The thermocouple probes are identical. They are positioned to give a homogeneous measurement.

- All the system components are located on the engine except the t4 indicator.

Main characteristics - Type : pyrometric device with thermocouple probes - Indication : degrees Celsius.

Main components -

Each probe contains a hot junction (Chromel and Alumel wires soldered together). The thermocouples are connected in parallel either to the aircraft indicator directly or through an amplifier providing analog and digital outputs. A thermocouple produces an electromotive force which is proportional to the temperature difference between the hot and the cold junction.

Thermocouple probes Thermocouple junction box (1S version) Harness Indicator.

The electromotive force is delivered to the t4 indicator (galvanometer graduated in degrees Celsius).

General operation The gas temperature (t4) is an operating parameter, particularly during engine starting. As it would be difficult to measure the turbine inlet temperature, the gas generator outlet temperature is measured.

The probes are wired in parallel. The reading obtained is an average temperature.

Measurement is made by thermocouples connected to an indicator. The system produces a voltage proportional to the temperature of a junction of two dissimilar metals. The voltage produced is measured by a galvanometer indicator which is graduated in degrees Celsius.




ARRIEL 1

Training Manual

THERMOCOUPLE PROBES THERMOCOUPLE JUNCTION BOX (1S version)

CHROMEL

HOT JUNCTION

COLD JUNCTION

t°

t4 TEMPERATURE INDICATION INDICATOR

THERMOCOUPLE JUNCTION BOX (1S version)

ALUMEL

GAS TEMPERATURE INDICATION For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

THERMOCOUPLE PROBES - GENERAL Function

Main components

The thermocouple probes measure the gas temperature (t4) at the gas generator outlet.

- For each probe : • Probe (sheath and thermocouple) • Mounting nut • Cable.

Position - Around the rear part of the combustion chamber casing.

Main characteristics - Type : Chromel-Alumel - Number : 3 probes - Alumel wire : magnetic, negative polarity - Chromel wire : non magnetic, positive polarity - Connection : in parallel.




ARRIEL 1

Training Manual

Type : Chromel - Alumel

PROBE

Number : 3 probes Alumel wire : Magnetic, negative polarity

CABLE

Chromel wire : Non magnetic, positive polarity MOUNTING NUT

Connection : In parallel

THERMOCOUPLE PROBES - GENERAL For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

THERMOCOUPLE JUNCTION BOX (1S VERSION) Operation Function The junction box forms the interface between the thermocouples and the indicator.

The t4 junction box provides a connection between the thermocouple probes and the aircraft indicator.

Position - On a bracket at the upper part of the power turbine.

Main characteristics - Type : box with connectors.

Main components - Junction box - Mounting flange - Connectors.

Description It includes the following connectors : - Thermocouple connectors - Indicator connectors. The connection system of chromel and alumel wires is in the box. For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

THERMOCOUPLE CONNECTOR

JUNCTION BOX INDICATOR CONNECTOR

THERMOCOUPLE CONNECTORS

Type : Box with connectors

THERMOCOUPLE

THERMOCOUPLE JUNCTION BOX (1S VERSION) For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

TORQUE INDICATION Function

Main components

To provide an indication of the engine torque measured at the reduction gearbox intermediate gear.

- Torquemeter piston - Electrical transmitter

Position

- Torque indicator.

- All the system components are located on the engine except the torque indicator.

Description


Refer to the following pages.

- Type : hydraulic torquemeter

General operation The reaction torque is transformed into axial force on the reduction gear intermediate pinion. The force is transmitted to a piston which determines an oil leak modulating a pressure representative of the torque. The pressure is transformed into electrical current supplied to the indicator by a transmitter.




ARRIEL 1

Training Manual

INDICATOR

TORQUE MEASUREMENT

TRANSMITTER

- Hydraulic torquemeter - Electrical transmitter - Torque indicator

LEAK

OIL PUMP

FILTER

TO ENGINE LUBRICATION

RESTRICTOR

TORQUEMETER PISTON

TORQUE INDICATION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

TORQUEMETER Function

Operation

To measure the torque transmitted to the output drive.

The torque on the output shaft is transmitted to the reduction gearbox. The intermediate gear, which has helical teeth, transmits the axial force to the piston, via the stop bearings. The movement of the intermediate gear/piston assembly varies the oil flow between the piston and the tube base. This pressure variation is felt by the torque transmitter.

Position - In the intermediate gear of the reduction gearbox.

Main characteristics - Type : hydraulic, using oil from the engine lubrication system.

Description The torquemeter piston is fitted into the hub of the intermediate gear of the reduction gearbox on three stop bearings. The head of the piston fits into a cavity in the reduction gearbox front casing. An oil tube passes through the hollow shaft of the piston and forms a passage between the piston and the tube base. Oil from the torquemeter system can pass through this passage.




ARRIEL 1

Training Manual

TORQUEMETER PISTON

INTERMEDIATE GEAR

STOP BEARINGS

OIL FLOW VARIATION

Type : Hydraulic

REDUCTION GEARBOX CASING OIL INLET (pressure modulated by the piston)

LUBRICATION TUBE

TORQUEMETER - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

TORQUE TRANSMITTER Function The transmitter transforms the hydraulic signal (modulated pressure from the piston) into an electrical signal and transmits it to the indicator.

Note : The torque transmitter or the indicator (according to version) is adjusted and matched to the reduction gearbox.

Position - Rear right hand side of the accessory gearbox.

Main characteristics - Type : inductive or resistive, according to version - Adjusted and matched to the reduction gearbox.

Main components - Transmitter.

Description The system includes : - A calibrated orifice - A transmitter - A pressure tapping point.




ARRIEL 1

Training Manual

PUMP PRESSURE

RESTRICTOR

TORQUEMETER PISTON MODULATED PRESSURE INDICATOR

Type : Inductive or resistive (according to version)

Note : The torque transmitter or the indicator (according to version) is adjusted and matched to the reduction gearbox.

TRANSMITTER

PRESSURE TAPPING

TORQUE TRANSMITTER For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

MISCELLANEOUS INDICATIONS GENERAL Function

Main components

The miscellaneous indications provide information about the engine operation

- Sensors and engine accessories (refer to corresponding chapters for more information)

Position

- Instruments and indicators on the instrument panel : • Indicators • Instruments.

- Engine - Aircraft.

Main characteristics - Electrical measurement circuit directly connected to indicators.




ARRIEL 1

Training Manual

Firewall

ENGINE

LIGHTS AND INSTRUMENTS

SENSORS AND ACCESSORIES AIRCRAFT

ENGINE

MISCELLANEOUS INDICATIONS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

MISCELLANEOUS INDICATIONS INDICATORS

INDICATIONS ACCORDING TO AIRCRAFT TYPE

There are several indicators which give information about the engine operation. These pages summarize the various lights which have already been dealt with in other chapters.

Position

FUEL INDICATING

- "Real time" fuel flow indicator - Total fuel flow indicator - Min fuel pressure indicator

OIL INDICATING

- Max oil temperature indication

AIR INDICATING

- Compressor bleed valve position indication (See chapter "air system") - Air intake anti-icing indication - Air intake sand filter condition indicator

- On the instrument panel.

Main characteristics - Indicating lights directly connected to engine sensors - Indications provided by the aircraft.

Lights directly connected to the engine sensors - Low oil pressure

POWER INDICATOR

- Electrical magnetic plug - Bleed valve position.


ARRIEL 1

- Power loss indication (For example N2 differential indicator in a twin engine configuration) - Power difference indication (For example torque differential indicator in a twin engine configuration)

OVERSPEED INDICATING

- Overspeed arming indicator (See chapter "electric system")

FIRE INDICATING

- Overtemperature detection in given engine area (See chapter "power plant installation")

"LIFE" INDICATOR

- Example : PSU control box on ARRIEL 1M (See chapter "electric system")



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Training Manual

+ 28 V Low oil pressure Bleed valve position Circuit breaker


ENGINE

INDICATING : • Fuel • Oil • Air • Power • Overspeed • Fire • "Life" HELICOPTER

MISCELLANEOUS INDICATIONS - INDICATORS For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

MISCELLANEOUS INDICATIONS N1 INDICATOR (1S VERSION) Function The two N1 indicators provide an analog (needle on a dial) and digital indication. Each indicator has a P0 pressure sensor and receives temperature t0 and N1 signals.

Position - Instrument panel.

Main characteristics - Analog indicator graduated in percent - Digital display unit in percent - Bleed valve and operating mode indicators.

Main components - Sensors - Indicator.

Operation In normal operation (twin engine), the system operates as a normal tachometer system. A connection between the two indicators allows passage to the OEI (One Engine Inoperative) mode when one of the two engines fails. The change to OEI mode is automatic when one N1 is lower than 66 % and the other one higher than 94 %.


In this configuration, the max speeds indicated are : - Max contingency : 101.7 % - Intermediate contingency : 100 % - Max continuous : 99 %. The indicator has an integrated microcalculator which allows indication of the OEI ratings corrected by flight conditions : - Normal mode: analog N = digital N = actual N - OEI mode : analog N = digital N = corrected N ƒ(Zp - t0) - Test : analog N indicates max contingency : i.e. 101.7 % digital N indicates actual max contingency ƒ(Zp and t0). In normal operating conditions, the analog indication is the same as the digital indication, but the available max contingency rating (depending upon the conditions) can be read by actuating the test button. This indication must be compared to a table located in the cockpit which shows the ratings as a function of Zp and t0. About 2 seconds after actuating the button, the digital indicator displays 188.8 and then returns to the normal indication. The OEI operating mode is indicated by the flashing of the decimal point and by the visual and audible warning system. The system also ensures : - The cut-out of the cabin heating - The cut-out of the EAPS if anti-icing is not selected.



ARRIEL 1

Training Manual

COMPRESSOR BLEED VALVE INDICATOR LIGHT

MAX TWIN ENGINE RATING (100%)

-3.5

+10

+25

+30

+35

+40

+45

+50

t0 (°C)

-1 102.7 102.7 102.6 102.5 102.3 102.1 101.8 +1 102.7 102.6 102.5 102.4 102.2 102.0 101.7

MAX AUTHORIZED SPEED AT GIVEN RATING (ZP/t0)

+3 96 95 75 55

102.7 102.6 102.4 102.3 102.1 101.9 101.7

98

+5

N1%

102.7 102.4 102.3 102.2 102.0 101.8

100

+7

BV

35

MAX INDICATED SPEED : i.e. 101.7%

N1

102.6 102.3 102.2 102.1 101.9

15

+9 102.4 102.2 102.1 102.0 +11

T

102.1 102.1 102.0 +13 102.0 102.0 +15

TEST

FLASHES WHEN INDICATING OEI RATING

MAX ONE ENGINE RATING (101.7%)

≈ 20°

Zp (ft x 1000)

EXAMPLE OF COMPARISON TABLE

t0

EXAMPLE OF LIMIT GRAPH

N1 INDICATOR

- 1S VERSION -

MISCELLANEOUS INDICATIONS - N1 INDICATOR For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

MISCELLANEOUS INDICATIONS CYCLE COUNTER Function

Operation

The cycle counter automatically carries out the calculations stated in the maintenance manual.

The input signal is the N1 speed supplied by a pick-up or by the tachometer generator.

Main components - Tachometer box with failure indicator

With this information, the system converts the engine actual operating cycles into "reference cycles" and displays the result.

- Display unit with N1 and N2 cycle displays

For the power turbine, the relationship is : 1 cycle = 1 start.

- Electrical connectors.

It is then possible to calculate the number of cycles of life limited parts.

Note : In the 1E and 1S version, a same box ensures the two functions of N2 overspeed protection and cycle counter.

The electronic box corresponding to an engine variant can perform some (or all) of the following functions : - Count engine operating cycles - Control electro-pneumatic compressor bleed valve - Protect against power turbine overspeed - Monitor the power turbine.




ARRIEL 1

Training Manual

FAILURE INDICATOR

DISPLAY UNIT

N1 AND N2 CYCLE DISPLAYS

N1, N2 AND 24 V INPUT

MISCELLANEOUS INDICATIONS - CYCLE COUNTER For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

9 - STARTING - Starting system ............................................................. 9.2 - Starter ............................................................................. 9.10 - Ignition system .............................................................. 9.16 - Ignition units .................................................................. 9.18 - Igniter plugs ................................................................... 9.22 - Ignition cables ................................................................ 9.26 to 9.27



STARTING

Training Manual

ARRIEL 1

STARTING SYSTEM - GENERAL Function

Main components

The starting system ensures starting (on the ground and in flight) and ventilation of the engine. It includes the following functions : cranking, fuel supply and ignition.

- Starter (cranking) - Ignition units and igniter plugs - Fuel system (supply, metering and delivery)

Position All the starting accessories are installed on the engine. Indicating and control components are supplied by the aircraft manufacturer.

- Indicating and control system : • Electrical system • Instruments.

Main characteristics - Starting envelope : according to version - Start duration : between 25 and 30 sec - Max ventilation time : less than 15 sec - Stabilisation time before shut-down : 60 sec - Run-down time : more than 30 sec from 30 to 0 % N1.



STARTING

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Training Manual

STARTER

IGNITION UNITS

IGNITER PLUGS

CRANKING

IGNITION

FUEL SUPPLY AND DISTRIBUTION

START CONTROL AND INDICATING

STARTING SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTING SYSTEM - DESCRIPTION Starter

The igniter plugs are installed close to the start injectors and are connected to the ignition units by two cables.

The starter is electrically supplied with direct current from the batteries through the aircraft electrical system. During starting, the starter drives the gas generator rotating assembly through the accessory drive train. At the end of starting, the electrical supply to the starter is cut. The starter is installed on the front face of the gearbox casing.

Ignition unit The ignition units are of high energy type. They transform the direct current voltage provided by the aircraft system into high energy voltage required for the igniter plug operation. The ignition units are located at the right side of the axial compressor casing.

Igniter plugs

Fuel system The fuel system supplies fuel to the start and main injectors. Refer to "FUEL SYSTEM" chapter for more details.

Control and indicating system The control system includes : - The cockpit components (fuses or circuit-breakers, ventilation and start push-buttons, the manual control lever) - The supply (28 V battery) - The accessory relay (to electrically supply the starting accessories) - The starter contactor - The overspeed box (twin engine only).

The engine has two igniter plugs which ignite the air fuel mixture sprayed by the start injectors.



STARTING

Training Manual

ARRIEL 1

STARTER CONTACTOR STARTERGENERATOR

CIRCUIT BREAKER

VENTILATION PUSH-BUTTON

START PUSH-BUTTON


ACCESSORY RELAY IGNITION UNITS OVERSPEED BOX

STARTING SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTING SYSTEM - OPERATION (1) This section deals with operating sequences associated with the starting system : start, stop and ventilation

Starting cycle

Ventilation cycle A ventilation consists of cranking the rotating assembly without supplying fuel or ignition (dry ventilation). It is used for cooling the engine or for maintenance procedures.

The starting cycle is characterised by the evolution of the engine parameters, especially the rotation speed and the gas temperature.

- Ventilation

The main points of the starting cycle are :

- Cranking of the rotating assembly

- Start selection

- End of ventilation and run-down.

- Self-sustaining speed (de-energisation of the starter and ignition units) - End of start (stabilisation at min power).

The ventilation cycle comprises the following phases :

Note : Ventilation time is limited to 15 sec. to avoid overheating of the starter motor.

Shut-down cycle This cycle comprises the following points : - Stabilisation at idle speed - Stop selection - Run-down and stop.



STARTING

ARRIEL 1

Training Manual N1 speed

Stop selection

Stabilisation

Run-down t4 gas temperature

N1

Time

SHUT-DOWN CYCLE Selfsustaining speed 45%

N1 speed

Ventilation off

≈ 200°C (injection wheel supply)

Selection Time

STARTING CYCLE

Selection

(15 sec. max)

Time

VENTILATION CYCLE

STARTING SYSTEM - OPERATION (1) For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTING SYSTEM - OPERATION (2) Start - Stop - Ventilation Power supply of the helicopter "ON"

Note : During the start it is necessary to control the acceleration of the engine, with the control lever, and to observe the N1 speed and T4 temperature.

- Valves closed, metering needle closed by the cam.

Stop

Booster pumps switched on - Purge of the fuel system with a return to the tank.

- After stabilisation pull the control lever to the "stop" position : the main valve closes. Note the run-down time.

Starting

Ventilation

- The control lever is moved to the "start" position : • slight opening of the main valve

- Power supply switched on

- Pushing the start push button initiates the start by electrically supplying : • the starter • the start injector electro-valve • the ignition system

- Press the ventilation button (max 15 secs) : • power supply to the starter motor via the start contactor.

- At 45 % of N1 (self sustaining speed) it is necessary to release the start push button to cut the supply to the start relay and accessories.



STARTING

Training Manual

ARRIEL 1

START - STOP - VENTILATION

STARTING SYSTEM - OPERATION (2) For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTER - GENERAL Function

Main components

The starter motor cranks the gas generator rotating assembly during starting and ventilation. At the end of starting (when the rotation speed is sufficient), the starter operates as a Direct Current generator.

The starter main components are : - The starter (starter/generator)

Position

- The supply terminals.

- On the front face of the accessory gearbox. It is secured by a clamp.

Interfaces - Starter electrical supply from the + 28 VDC supply bus bar through the starter contactor


- Drive of the gas generator rotating assembly through the accessory drive train

- Supplied by the aircraft manufacturer - Type : starter-generator - Supply : VDC through heavy duty cables (32 V max)


- The mounting flange

- Direct current supply to the aircraft system from the starter generator when the starting phase is completed.


STARTING

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Training Manual

TERMINALS

MOUNTING FLANGE

Aircraft supply Type : Starter-generator Electrical supply : VDC through heavy duty cables (32 V max)

STARTER

STARTER - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTER - DESCRIPTION Description The starter comprises the following components : - Connection terminals • Excitation • Generator • Negative pole • Starter • Balance - Casing - Mounting flange - Brushes - Windings (stator and rotor) - Cooling fan - Drive shaft - Commutator.



STARTING

ARRIEL 1

Training Manual

SUPPLY TERMINALS GENERATOR STARTER EXCITATION NEGATIVE POLE BALANCE

MOUNTING FLANGE (on accessory gearbox)

CASING

BRUSHES

COOLING FAN

DRIVE SHAFT

WINDINGS (stator and rotor)

COMMUTATOR

STARTER - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

STARTER - OPERATION Operation Engine cranking When "START" is selected the starter contactor closes and connects the aircraft DC bus bar to the starter. The starter then cranks the rotating assembly through the accessory drive train. The torque on the starter shaft is inversely proportional to the gas generator speed and will be higher when the atmospheric temperature is low. The N1 increases up to self-sustaining speed (45 %) at which point the torque becomes negative. The supply to the starter is cut by the opening of the starter contactor. Electrical generation At the end of the start cycle the starter is no longer electrically supplied and it is driven by the gas generator through the accessory drive train. Thus it acts as an electrical generator and supplies current to the aircraft circuit.



STARTING

ARRIEL 1

Training Manual

START TORQUE TORQUE WITH A DECREASING AMBIENT TEMPERATURE

GAS GENERATOR SPEED 0

SELF-SUSTAINING SPEED 45 % STARTER

GENERATOR

+D +G Ex +VDC

SUPPLY TO STARTER RELAY

+

Eq

SUPPLY TO THE ELECTRICAL CIRCUIT

STARTER - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITION SYSTEM Function

Main components

This system ensures the ignition of the fuel sprayed by the start injectors into the combustion chamber.

- Ignition units - Ignition cables

Position

- Igniter plugs.

All the ignition system components are installed on the engine, except the electrical supply circuit.


Note : Refer to the following pages for the description and operation of these components.

- Type : High Energy (HE) - Supply voltage : 10 to 32 VDC.



STARTING

ARRIEL 1

Training Manual

IGNITER PLUGS

IGNITION CABLES

IGNITION UNITS

Type : High Energy

28 V DC Bus

Ignition cables

Ignition unit Igniter plugs

Circuitbreaker

Ignition unit Accessory relay

Supply voltage : 10 to 32 VDC

IGNITION SYSTEM For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITION UNITS - GENERAL Function

Main components

The ignition units transform the input voltage into high energy output.

- Ignition units - Input electrical connector

Position

- Output electrical connectors

- Mounted on a support at the front right part of the engine.

- Mounting flanges.

Main characteristics - Type : High Energy - Supply voltage: 10 to 32 VDC - Output voltage : 2000 VAC - Quantity : 2.



STARTING

ARRIEL 1

Training Manual

Type : High Energy (HE)

MOUNTING FLANGES

Supply voltage : 10 to 32 VDC Output voltage : 2000 VAC Quantity : 2 IGNITION UNITS


IGNITION UNITS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITION UNITS - DESCRIPTION OPERATION Description

Operation

The ignition unit comprises the following components :

The ignition unit is supplied with 28 VDC.

- An input circuit which includes the connector and the alternating-direct converter

The converter transforms the DC voltage into an alternating voltage.

- A transformer

The transformer amplifies the alternating voltage and supplies the rectifier.

- An output circuit which includes : • A rectifier • A capacitor • A discharge tube.

The rectifier selects the positive phases and loads the capacitors. The capacitor accumulates the electrical loads (positive phases) and discharges at regular intervals into the discharge tube. The discharge tube controls the phases of loading and discharge. Then the high energy voltage is delivered to the igniter plugs through the ignition cables (2000 Volts).



STARTING

ARRIEL 1

Training Manual

VDC

VAC

0

t

0

VAC (kV)

t

0

t

+

CAPACITOR DISCHARGE

V (kV)

0

t

IGNITER PLUG RECTIFIER

2000 V

DISCHARGE TUBE

DIRECT CURRENT INPUT 28 VDC

CAPACITOR

-

CONVERTER

TRANSFORMER

IGNITION UNITS - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITER PLUGS - GENERAL Function

Main components

The igniter plugs produce sparks to ignite the fuel sprayed by the start injectors.

- Plug body - Electrode

Position - Mounted beside the start injectors on either side of the combustion chamber casing.


- Mounting flange (2 bolts on the combustion chamber boss) - Electrical connector (connection with the ignition unit) or ignition cable (according to version).

- Type : High Energy (HE), surface discharge - Quantity : 2.



STARTING

ARRIEL 1

Training Manual

IGNITION CABLE


PLUG BODY ELECTRODE

BEFORE MOD TU 271A

Type : High Energy Surface discharge IGNITION CABLE Quantity : 2 ELECTRICAL CONNECTOR

MOUNTING FLANGE PLUG BODY

AFTER MOD TU 271A

IGNITER PLUGS - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITER PLUGS - DESCRIPTION OPERATION Description

Operation

An igniter plug comprises :

The high energy current produced by the ignition unit is supplied to the central electrode of the igniter plug. It discharges, across the semi-conductor to the plug body causing a powerful spark.

- An external body connected to the negative terminal - A semi-conductor fitted in the tip of the plug

This spark ignites the air fuel mixture sprayed into the combustion chamber by the start injector.

- An insulator - A central electrode connected to the positive terminal - An electrical connector for connection to the ignition unit (or the ignition cable integral with igniter) - Seals and spacers.



STARTING

ARRIEL 1

Training Manual

ELECTRICAL CONNECTOR (connection with the ignition unit) INJECTORS

IGNITER PLUG

SEALS AND SPACERS IGNITER PLUG

EXTERNAL BODY (-)

Spark

CENTRAL ELECTRODE (+)

COMBUSTION CHAMBER

DESCRIPTION

SEMI CONDUCTOR

INSULATOR

OPERATION

IGNITER PLUGS - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

IGNITION CABLES (POST MOD TU271A) Function

Main components

The ignition cables supply the high energy current (produced by the ignition units) to the igniter plugs.

Position - Between the ignition unit and the plugs.

Main characteristics - Type : multi-core nickel-plated copper wire - Number : 2 identical independent cables - Shielding : triple braided - Voltage rating : 5 kVolts.

- Igniter plug cable connector - Ignition cable (wire and shield) - Ignition unit connector.

Description One ignition cable includes : - A nickel-plated copper multicore - An outer shielding (stainless steel braid) - Two inner shields (silver-plated copper braid) - Two stainless steel rigid end fittings - Two electrical connectors • One igniter plug connector (ceramic insulator, spring and nut) • One ignition unit connector (teflon insulator, silicone joint, spring and nut).



STARTING

Training Manual

ELECTRICAL CONNECTOR (to the igniter plug)

ARRIEL 1 ELECTRICAL CONNECTOR (to the ignition unit)

Type : Multicore nickel-plated copper wire Number : 2 identical independent cables Shielding : Triple braided Operating voltage : 5 kVolts

IGNITION CABLE (wire and shield)

IGNITION CABLES (POST MOD TU271A) For training purposes only © Copyright - TURBOMECA - 2000


STARTING

Training Manual

ARRIEL 1

10 - ELECTRICAL SYSTEM - Electrical system ........................................................... 10.2 - Electrical accessories .................................................... 10.4 - Power turbine overspeed safety system ....................... 10.6 - Power turbine overspeed sensor................................... 10.10 - Tachometer box.............................................................. 10.14 - Super contingency power system ................................ 10.24 - Electrical harnesses ...................................................... 10.28 to 10.29



ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

ELECTRICAL SYSTEM Function

Main components

The system contributes to the various indicating and control functions of the engine :

- Engine electrical components (indicating components and sensors)

- Indicating

- Control and indicating components (aircraft)

- Fuel control

- Electrical harnesses.

- Safety systems

Main characteristics - Power supply : 28 VDC from aircraft electrical system



ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

ACCESSORIES AND SENSORS

Power supply : 28 VDC from aircraft

ELECTRICAL HARNESSES

ELECTRICAL SYSTEM For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

ELECTRICAL ACCESSORIES - GENERAL Function

Engine accessories supplied by the engine manufacturer

The electrical accessories are involved in various engine functions. This chapter summarises the various accessories. For the detail of each one refer to the appropriate chapter.

Electrical accessory classification The accessories can be classified as follows : - Control components (buttons, selectors, potentiometers …) - Indicating components (indicators, lights, displays …) - Engine accessories (controlled accessories, sensors connected to the aircraft).

Control components - Switch push buttons, relay circuit-breakers, etc...

Indicating components

-

Igniter plug Ignition Unit Start electro-valve Power turbine overspeed electro-valve (twin engine configuration) Super contingency power electro-valve (example : 1M) Compressor electro-valve Bleed valve microswitch (position) Oil pressure switch Electrical magnetic plug Tachometer transmitter Power turbine overspeed probe (twin engine) Pyrometric harness Torque transmitter Tachometer box Super-contingency power box (example : 1M).

- Light, indicators, etc...



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

CONTROLE AND INDICATING COMPONENTS

ENGINE ACCESSORIES

ELECTRICAL ACCESSORIES - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

POWER TURBINE OVERSPEED SAFETY SYSTEM - GENERAL Function

Main components

The safety system causes the immediate shut-down of the engine in the event of power turbine overspeed.

- Speed sensor

The system (mainly designed to protect against shearing of the power shaft) requires a very quick response and a high reliability.

- Overspeed electro-valve.

- Tachometer box

This safety system is only installed on twin-engine configurations.

Position All the components are installed on the engine except the tachometer box which is mounted on the aircraft.

Main characteristics Overspeed setting : 120 % N2 - Automatic test : • for each start • during periodic inspection.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

OVERSPEED SENSOR

TACHOMETER BOX OVERSPEED ELECTRO-VALVE

POWER TURBINE OVERSPEED SAFETY SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

POWER TURBINE OVERSPEED SYSTEM DESCRIPTION - OPERATION Description

Operation

The speed sensor is mounted facing two phonic wheels with a different number of teeth, mounted on the turbine shaft. It is connected to the tachometer box (in the aircraft).

In the event of an overspeed, when the tachometer box receives two frequency signals, it energises the overspeed electro-valve to move to drain position causing the engine shut-down.

The tachometer box electrically supplies the overspeed electro-valve on the overspeed and drain valve.



ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

OVERSPEED ELECTRO-VALVE SPEED SENSOR

TACHOMETER BOX

POWER TURBINE OVERSPEED SAFETY SYSTEM DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

POWER TURBINE OVERSPEED SENSOR GENERAL Function

Main components

The power turbine overspeed sensor monitors N2 and transmits the signal to the tachometer box (twin-engine version).

- Sensor

Position

- Locating dowel - Hollow bolt.

Screwed into the bottom of module 4 casing.

Main characteristics - Double pick-up - Type : magnetic.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

PHONIC WHEELS

SENSOR LOCATING DOWEL

Double pick-up

HOLLOW BOLT

Type : Magnetic

POWER TURBINE OVERSPEED SENSOR - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

POWER TURBINE OVERSPEED SENSOR OPERATION Description

Operation

The sensor is fitted facing the phonic wheels, it includes two electro-magnetic pick-ups.

The passage of the teeth in front of the electro-magnetic sensor induces two alternating currents having a frequency proportional to the speed and to the number of teeth :

The sensor is secured by a hollow bolt and is fitted with a locating pin to ensure the correct orientation.

nd x N Frequency F = 60 (nd = number of teeth, N = rotation speed in Rpm) As the phonic wheels don't have the same number of teeth, the double sensor gives two different frenquencies proportional to the speed.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TO THE TACHOMETER BOX

PHONIC WHEELS

SENSOR PHONIC WHEEL SENSOR

HOLLOW BOLT F = nd x N 60

TACHOMETER BOX

ELECTRO-MAGNETIC PICK-UP

PHONIC WHEEL

POWER TURBINE OVERSPEED SENSOR DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

TACHOMETER BOX - GENERAL Function

Main components

To supply the overspeed electro-valve in case of an overspeed detection and to control the operation of the bleed valve (according to version).

- Push-buttons • test • rearming

Position

or selector according to version

- In the aircraft

- Electrical connector(s).

Main characteristics - Electronic box - Automatic test - Periodic test.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TEST PUSH-BUTTON TEST SELECTOR

REARMING PUSH-BUTTON

TEST

ELECTRICAL CONNECTOR FOR THE COMPRESSOR BLEED VALVE CONTROL

ELECTRICAL CONNECTOR OVERSPEED CONNECTOR

TACHOMETER BOX - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

TACHOMETER BOX - DESCRIPTION Description The tachometer box is mounted in the aircraft, it is connected to the overspeed sensor by an electrical harness. It includes two frequency detectors, a V relay, a bi-stable relay S and S', a rearming and a test push button. A cross monitoring system between the two overspeed boxes inhibits the overspeed system of the other engine in case of overspeed.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TEST OSCILLATOR

S

120 %

N2

120 %

N2

V

OVERSPEED ELECTRO-VALVE ENGINE INHIBITION OF THE STARTING SHUT-DOWN INHIBITION OF THE ENGINE 2 SYSTEM 25 % S' REARMING

25 %

EVENTUAL INHIBITION OF THIS SYSTEM

TACHOMETER BOX - DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

TACHOMETER BOX - OPERATION (1) Power on At power on, the sensors give the F1 and F2 frequencies to frequency detectors which supply the light through the mutual monitoring system (up 25 % of N2). An eventual rearming is possible.

Overspeed condition In the event of N2 overspeed (N2 ≈ 120 %) the two signals of N2 (F1 and F2) are supplied to the two frequency detectors which complete the circuit through relay V. Relay V closes its contacts : • supplying relay S • breaking the circuit of the other engine. The contacts of relay S • open the other engine's overspeed circuit • supply the overspeed solenoid • open the start circuit • open the overspeed light circuit.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TEST OSCILLATOR

POWER ON - The light turns on (up to 25 % of N2) - Rearming (eventually)

S

120 %

N2

120 %

N2

V

OVERSPEED - Supply of the monostable relay V - Supply of the bi-stable relay S - Supply of the overspeed electro-valve - Inhibition of engine 2 system - Inhibition of the start


25 %

EVENTUAL INHIBITION OF THIS SYSTEM POWER ON OVERSPEED

TACHOMETER BOX - OPERATION (1) For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

TACHOMETER BOX - OPERATION (2) Automatic monitoring (A, B, C, D, K, M versions) The condition of the pick-up signals is checked at each start with the light turning-off above 25 % N2.

Periodic test Engine stopped, operation of the push button simulates an overspeed : • the light goes off • the electro-valve is supplied • the start system is inhibited After this test it is necessary to rearm the system.

Rearming When the rearm push button is pressed the relay S' is supplied and the relay returns to the normal position.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

OVERSPEED MANUAL TEST

TEST OSCILLATOR

- Supply of the oscillator 120 % * - Oscillator inhibited for N2 > 25 %

S

N2 (y)

OK

OK

N2

120 %

N2

V

AUTOMATIC MONITORING A, B, C ,D, K, M VERSION : whatever N1 N2 (x)

120 %

OVERSPEED ELECTRO-VALVE ENGINE INHIBITION OF THE STARTING

Light off SHUT-DOWN

OK

0

Light on

0

OK

Light on

0

0

Light on

INHIBITION OF THE ENGINE 2 SYSTEM 25 % S' REARMING

OVERSPEED MANUAL TEST

25 %

EVENTUAL INHIBITION OF THIS SYSTEM AUTOMATIC MONITORING



ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

TACHOMETER BOX - OPERATION (3) Automatic monitoring (1E, 1S versions) This protection doesn't exist on all boxes. - Above 25 % N2 and below 83 % N1 : the loss of one N2 speed signal is indicated by the light staying "on". - Above 25 % N2 and 83 % N1 : • the loss of one N2 speed signal is also indicated by the light staying "on" • the loss of two N2 speed signals causes the engine to be shut down by the overspeed system. - Above 25 % N2. • the loss of the N1 speed signal or any defect of the protection stage is indicated by the flashing of the light.

Note : In all cases of engine shut down by overspeed, starting is not possible.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TEST

AUTOMATIC MONITORING 1S, 1E VERSION : N1 < 83 % N2 (x)

N2 (y)

OK

OK

Light off

OK

0

Light on

0

OK

Light on

0

0

Light on

OSCILLATOR

S

120 %

N2

120 %

N2

V

OVERSPEED ELECTRO-VALVE

N1 > 83 % ENGINE N2 (x)

INHIBITION OF THE STARTING

N2 (y) SHUT-DOWN

OK

OK

Light off

OK

0

Light on

0

OK

Light on

0

0

INHIBITION OF THE ENGINE 2 SYSTEM 25 %

Engine shut-down

S' 1S, 1E

N2 > 25 %

REARMING VERSION

25 %

N1 OK 0

Light off

N1

83 %

Light flashing 1E, 1S VERSION MONITORING

EVENTUAL INHIBITION OF THIS SYSTEM



ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

SUPER CONTINGENCY POWER SYSTEM GENERAL Function

Main components

The purpose of this system is to provide on extreme power rating : super contingency power rating. This system is only available on some versions.

- Control box - Super contingency power electro-valve.

The control box, delivered with the engine ensures: - the recording and display of the engine operating hours in hundreths of an hour.

Note : The S.C.P. control box is associated with the module M03.

- the recording and indication by a red flag of the use of S.C.P. - the ouput of a duplicate signal to a flashing light in the cockpit to indicate use of S.C.P.

Position The electro-valve is on the FCU, the control box in the helicopter.

Main characteristics - Selection by button on the collective pitch lever.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

S.C.P. ELECTRO-VALVE

S.C.P. CONTROL BOX (associated with module M03)

RED FLAG

ENGINE HOUR COUNTER

ELECTRICAL CONNECTORS

SUPER CONTINGENCY POWER SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

SUPER CONTINGENCY POWER SYSTEM DESCRIPTION - OPERATION Description The electro-valve on the fuel control unit opens when electrically supplied to permit an increase of modulated pressure and therefore an increase of the max available rating. The control box belongs to module n° 03, it indicates the engine hours and the operation of S.C.P. The system includes : • a selector on the collective pitch-lever • an automatic armament switch in the torque indicating system. • a flasher relay • an indicating device (light and flag)

Operation

The detection logic in the torque indicating system closes its contact thus supplying, through the pilot's selector, the S.C.P. electro-valves of both engines and the S.C.P. light in the cockpit. Super Contingency Power will now be available on the operative engine. Rating detection From 50 to 102.5 % N1 the S.C.P. box counts the engine hours. From 102.5 to 103.8 % N1, that is in S.C.P. mode, the engine hours counting is increased by a multiplication factor of 4.4. The S.C.P. light is on. If the N1 remains above 103.8 % for more than 5 seconds the bi-stable relay is supplied and relay (C) is supplied causing the flashing of the S.C.P. light. Simultaneously the red flag is activated and appears in the window.

S.C.P. Arming Two conditions are necessary for the arming of the S.C.P. system: - the pilot must select S.C.P. - there must be a torque difference between the engines ≥ 22 %.


Note 1 : Normal max N1 is 102.4 % for the Arriel 1M1 / 1MN1 without S.C.P. In S.C.P. mode the max N1 is 105 %. Note 2 : The maximum authorised accumulated operating time in S.C.P. is 1 minute. The use of this rating requires replacement of the engine and the S.C.P. box.


ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

TORQUE INDICATOR

+ 28 V

TO OTHER ENGINE (SCP electro-valve)

D ≥ 22%

COLLECTIF PITCH S.C.P. SELECTOR

RELAY TO ELECTRO-VALVES

S.C.P. + 28 V FLASHER UNIT C RELAY

S.C.P. CONTROL BOX

BI-STABLE RELAY + 28 V

FLAG N1 ≥ 103.8 %

T:5 secs

N1 ≥ 102.5 % (T x4.4) SIGNAL FROM N1 TACHO. GEN.

N1 ≥ 50 %

(T x1)

ENG. HOURS COUNTER

S.C.P. ELECTRO-VALVE

WINDOW

TO N1 INDICATOR

SUPER CONTINGENCY POWER SYSTEM DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

ELECTRICAL HARNESSES Function Harnesses link the engine accessories to the aircraft.

Description and operation All engine versions have a multi-pin plug for the engine/ aircraft interface and a second electrical plug for the pyrometric system (except on ARRIEL 1S1 : only one electrical plug for the two harnesses). On the twin-engine version : a harness for the speed detection to stop the engine in case of overspeed.

Note : The starter-generator cables must also be mentioned.



ELECTRICAL SYSTEM

ARRIEL 1

Training Manual

SPEED DETECTION HARNESS FOR THE OVERSPEED SYSTEM (twin-engine version)

PYROMETRIC HARNESS

ACCESSORY HARNESS

ARRIEL 1S1 : only one connector

ELECTRICAL HARNESSES For training purposes only © Copyright - TURBOMECA - 2000


ELECTRICAL SYSTEM

Training Manual

ARRIEL 1

11 - ENGINE INSTALLATION - Engine compartment ..................................................... - Engine mounting............................................................ - Power drive .................................................................... - Air intake........................................................................ - Exhaust system .............................................................. - Engine system interfaces .............................................. • Oil system .................................................................................... • Aircraft LP fuel system .............................................................. • Manual controls .......................................................................... • Air system.................................................................................... - Drain system .................................................................. - Fire protection ............................................................... For training purposes only © Copyright - TURBOMECA - 2000

11.2 11.4 11.8 11.10 11.12 11.14 11.14 11.16 11.18 11.20 11.22 11.24 to 11.25 11.1


ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE COMPARTMENT Function

Description

The engine compartment accommodates the engines and ensures their ventilation.

A typical twin-engine installation includes the following components :

Position

- Two areas separated by a central firewall : • Right engine area • Left engine area

- At the rear of the helicopter main gearbox.

Main characteristics - Insulated compartments - Compartment ventilation by air circulation.

Main components - Firewalls - Cowlings - Support platform.

- Three main firewalls : • Front firewall • Rear firewall • Central firewall. - The main engine mountings - Two main cowlings : • The air inlet cowling which permits access to the air intake • The engine cowling which permits access to the engine and to the exhaust system. The compartment ventilation is ensured by air circulation in order to maintain an acceptable temperature in the various areas. The ventilation can be increased by the compressor bleed valve air discharging into the engine compartment.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

ENGINE

SUPPORT PLATFORM

FRONT FIREWALL

ENGINE MOUNTING

AIR INLET COWLING

MAIN GEARBOX

EXAMPLE OF SINGLE ENGINE INSTALLATION

CENTRAL FIREWALL

REAR FIREWALL

ENGINE COWLING

EXAMPLE OF TWIN-ENGINE INSTALLATION

ENGINE COMPARTMENT For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE MOUNTING - GENERAL Function The engine mountings attach the engine to the airframe. The lifting brackets permit the removal and installation of the engine.

Position - Front mounting : at the front lower part of the accessory gearbox casing - Rear mounting : at the front lower part of the reduction gearbox casing, or on the protection tube (according to version) - Lifting brackets : 2 at the front part and one at the rear.

Main components - Front mounting : flange or yoke (according to version) - Rear mounting : clamps and cradle (according to version) - Engine lifting points : • two brackets on the centrifugal (compressor casing flange) • one bracket on the power turbine casing flange.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

FRONT LIFTING BRACKETS

FRONT FLANGE

REAR LIFTING BRACKET

CRADLE

CLAMPS

ENGINE MOUNTING - GENERAL For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE MOUNTING - FUNCTIONAL DESCRIPTION There are two types of engine mounting depending on the engine variant. - Variants A, B, C, D and M : Front support - ring of bolts on the front flange. Rear support - a cradle under the protection tube, secured by two clamps. - Variants E, K and S : Front support - yoke bolted to the front face of the accessory gearbox, supported on two trunnion mounts. Rear support - a rod connects to the bracket on the bottom of module 5.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

MOUNTING BY THE FRONT SUPPORT CASING FLANGE

MOUNTING BY CLAMPS ON THE PROTECTION TUBE

TYPE A - B - C - D - M

TYPE A - B - C - D - M

MOUNTING BY TWO ATTACHMENT POINTS ON THE AIRFRAME

REAR MOUNTING TYPE E - K - S

TYPE E - K - S

ENGINE MOUNTING - FUNCTIONAL DESCRIPTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

POWER DRIVE Function


The power drive transmits the engine power to the helicopter transmission system.

The engine drive shaft consists of a steel tube, fitted with the following elements at each end :

The link is made by a transmission shaft designed to absorb the engine torque and slight misalignements (supply by aircraft manufacturer or TURBOMECA according to version)

- A triangular flange connected to the MGB input flange with a flexible coupling

Position - Between the engine and the helicopter main gearbox.

Main characteristics - Shaft designed to absorb the engine torque and slight misalignments

- A splined flange, connected to an adaptor flange which is connected to the engine drive shaft flange with a flector. The flexible couplings are installed between the flanges. They transmit torque, absorb shock and vibration and allow slight misalignment.

Note : In single engine versions, the free wheel unit drives the main gearbox and the tail rotor shaft drive.

- Rotation speed : 6000 RPM at 100 %.

Main components The main components are : • The engine drive shaft flange • The flector (engine end) • The adapting flange • The drive shaft • The flexible coupling (MGB end) • The main gearbox input flange.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

FLECTOR

ENGINE DRIVE-FLANGE

DRIVE SHAFT

1S VERSION

SPLINES

ADAPTOR FLANGE (splined) FLEXIBLE COUPLING MAIN GEARBOX INPUT FLANGE 1E VERSION

POWER DRIVE For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

AIR INTAKE Function


The air intake system directs the ambient air into the engine.

A circular flange on the compressor casing permits connection of the aircraft air intake duct. The admission of air can be made through a static or a dynamic intake which can be provided with protection devices (filters, antiicing...). A pressurized seal can also be fitted to improve the connection sealing. Some versions are provided with a device for compressor washing.

Position - In front of the engine.

Main characteristics - Type : Static or dynamic, annular - Air flow : 2.5 kg/s (5.5 lb/sec.).

Main components - Helicopter air intake - Intake duct - Anti-icing system.



ENGINE INSTALLATION

Training Manual

AIR DUCT

ANTI-ICING

ARRIEL 1

SEAL

FILTER

UNION FOR COMPRESSOR WASHING

AIR INTAKE For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

EXHAUST SYSTEM Function


The exhaust system discharges the exhaust gas overboard.

The exhaust expels the gases directly but it can be adapted to the aircraft by means of an extension. The engine compartment ventilation can be accelerated by venturi effect between the engine exhaust pipe and the aircraft duct.

Position - At the rear of the engine.

Main characteristics - Type : divergent - Gas temperature : 600 °C (1080 °F).

Main components - Engine exhaust pipe - Exhaust extension.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

EXHAUST PIPE

EXTENSION

VENTURI TO ACCELERATE THE COMPARTMENT VENTILATION

EXHAUST SYSTEM For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE SYSTEM INTERFACES (1) Oil system interfaces For each engine, the oil system has three interfaces as follows : - Oil return line to the aircraft oil cooler - Oil supply line to the oil pump pack - The vent line : from the oil tank to the accessory gearbox and to the exhaust.



ENGINE INSTALLATION

Training Manual

OIL SUPPLY

AIRCRAFT

ARRIEL 1

BREATHING

ENGINE OIL RETURN TO THE COOLER

OIL SYSTEM INTERFACES

ENGINE SYSTEM INTERFACES (1) For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE SYSTEM INTERFACES (2) Aircraft LP fuel system


Function

The interface comprises the union on the FCU and return to tank union. The aircraft system may include various devices : vent, level indication, filler neck, booster pump, pressure indicator, flowmeter. The booster pump will prime the engine system and prevent cavitation of the pump.

The system supplies the engine with fuel under determined conditions of pressure, flow, temperature and filtering. Main characteristics - Filtering 10 micron. Main components

The filtering unit, normally fitted with a pre-blockage indicator and a by-pass valve is in the line before the shutoff valve which is used to isolate the engine compartment from the aircraft system.

- Fuel tank - Booster pump - Filter assembly

Note : In the 1S, 1E versions, the fuel inlet union is located on the LP fuel system, located under the engine.

- Fuel shut-off valve - Fuel inlet union - Return to tank union.



ENGINE INSTALLATION

Training Manual

ARRIEL 1 HP PUMP PRESSURE (FCU)

FUEL INLET UNION FUEL SHUT-OFF VALVE

RETURN TO TANK UNION FUEL SUCTION FROM TANK FILTER UNIT (filtering 10 microns)

FUEL TANK

1S, 1E VERSIONS

BOOSTER PUMP (except 1S)

AIRCRAFT LP FUEL SYSTEM



ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE SYSTEM INTERFACES (3) Manual controls Function To allow the control of the fuel valves and of the anticipator. Position The engine control lever and the collective pitch lever are in the cockpit and are mechanically connected to the F.C.U. Main components - Control lever - Collective pitch lever - Fuel control unit. Functional description - Engine control lever (Lever actuating 2 valves and a cam in the fuel control unit : see chapter "fuel system" and aircraft manuals for the mechanical linkage). - Anticipator control (Linkage with the helicopter collective pitch : see operation of the anticipator in the chapter "engine control" and details of the mechanical connection in the aircraft manuals).



ENGINE INSTALLATION

ARRIEL 1

Training Manual

FUEL VALVE CONTROL

CONTROL LEVER

ANTICIPATOR CONTROL

COLLECTIVE PITCH LEVER

MANUAL CONTROLS



ENGINE INSTALLATION

Training Manual

ARRIEL 1

ENGINE SYSTEM INTERFACES (4) Air system

Possible uses of the air

Function

- Cabin heating

The system provides warm compressed air to the aircraft for the aircraft services.

- Pressurized seal

Position

- Air intake anti-icing - Particle separator...

One tapping boss on each side of the centrifugal compressor casing. Main components

Note : Refer to aircraft manuals for detailed description of these systems.

Air tapping points (x 2). Functional description Aircraft pipes can be connected to the two tapping points to supply a given flow of P2 air. The flow is limited by restrictors but any air bleed affects engine performance.



ENGINE INSTALLATION

ARRIEL 1

Training Manual

P2 P2 TAPPING

AIR SYSTEM



ENGINE INSTALLATION

Training Manual

ARRIEL 1

DRAIN SYSTEM Function

Description

To drain fluids from certain engine components.

A drain collector is fitted on a bracket at the bottom of the accessory gearbox casing and is connected by a flexible pipe to an aircraft drain.

Position - Various pipelines on the engine connected to the aircraft drain system.

Four drain tubes are connected to the drain collector, the output casing drain, the pump drive drain, the combustion chamber drain and the overspeed and drain valve.


The gas generator rear bearing vent pipe vents into the engine compartment.

- Stainless steel tubes.

The engine breather comprises a T union on the upper right side of the accessory gearbox. Connected to the front of this union is the oil tank breather and to the rear, the pipe which discharges into the exhaust.

Main components -

Combustion chamber drain valve General vent F.C.U. drive drain Overspeed and drain valve Exhaust pipe drain Output shaft casing drain Air vent of the Gas generator rear bearing Rear bearing collector drain.


The rear bearing supply collector has a drain into the engine compartment. The exhaust pipe drain connects into a pipe which is connected to an aircraft overboard drain.


ENGINE INSTALLATION

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Training Manual

COMBUSTION CHAMBER DRAIN VALVE

AIR VENT OF THE GAS GENERATOR REAR BEARING

GENERAL VENT


FCU DRIVE DRAIN

OUTPUT SHAFT CASING DRAIN EXHAUST PIPE DRAIN

TO AIRCRAFT

REAR BEARING COLLECTOR DRAIN

DRAIN SYSTEM For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

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Training Manual

FIRE PROTECTION Function


The fire protection system comprises overtemperature detection in the various engine areas, the indication in the cockpit, the extinguishing function.

The detection is ensured by non sealed detectors with normally closed contact (1A, B, C, D, K, M) or one sealed detector with normally open contact (1E) or by means of an aircraft mounted optical device (1S).


Some detectors have a built-in resistor which permits the discrimination of circuit conditions (1C, D, K, M) : normal, overtemp, harness failed.

- Engine manufacturer supply (except 1S) • Bi-metallic detectors.

In the case of detectors with normally closed contact, the detectors are installed in series and have a setting which corresponds to the engine area of location ("cold" area or "hot" area) and thus they are not interchangeable.

- Aircraft manufacturer supply • Optical detectors (1S only) • Indicating system • Extinguishing system.

Main components - Engine • Six detectors (except : 1E : one detector, 1S : no detector) • Harness (fire proof cables).

Note : "cold" area or area 1 : area located forward of the junction of the compressor and the combustion chamber mounting flanges. "hot" area or area 2 : area located rear of the same junction.

- Aircraft • Two detectors (1S only) • Extinguishing system • Test system.



ENGINE INSTALLATION

Training Manual

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1A,B,C,D,K,M (6 detectors)

1E (1 detector)

NON SEALED DETECTOR (1A, B, C, D, K, M )

SEALED DETECTOR AT REST (1E )

1S (2 detectors on aircraft) POSITION OF DETECTORS

Area 1 (cold)

Area 2 (hot)

+ Alarm

Detection logic

+ Aircraft

Engine

Test button EXTINGUISHING SYSTEM (bottle, manifold... )

+

Extinguishing button

EXAMPLE OF FIRE DETECTION / EXTINGUISHING SYSTEM

FIRE PROTECTION For training purposes only © Copyright - TURBOMECA - 2000


ENGINE INSTALLATION

Training Manual

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12 - OPERATING LIMITATIONS AND PROCEDURES - Operating limitations ................................................... 12.2 - Operating procedures .................................................. 12.6 to 12.9



OPERATING LIMITATIONS AND PROCEDURES

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OPERATING LIMITATIONS (1) The engine operating limitations are defined in the official manuals, however the following figures provide information for training purposes.

Power turbine rotation speed

Operating envelope

- Overspeed : 120 % N2 (twin-engine).

The engine is designed to operate within a clearly defined climatic range of temperature and pressure altitude e.g. : -50 °C to +50 °C (-58 °F to 122 °F) and -500 m to +6000 m (-1640 ft to 19680 ft).

The main limitation is :

t4 gas temperature These figures vary according to version : - Max during start : 750 °C

The starting envelope also has given limits e.g. : -500 m to 4500 m (-1640 ft to 14760 ft) and -50 °C to +50 °C (-58 °F to 122 °F) depending on the fuel and oil used.

- Max (t < 10 sec.) : 865 °C

Gas generator rotation speed

- Max take-off : 912 °C (< 5 min).

The main limitations are :

- Max OEI (2 min 30 sec) : 941 °C

- AEO max T/O 5 min max continuous : 98 % N1 - OEI max contingency - (2 min 30 sec) inter contingency - unlimited super contingency - according to version.




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Training Manual

FLIGHT ENVELOPE

POWER TURBINE ROTATION SPEED

Zp

Twin-engine : - Power turbine overspeed 120 % N2

- Flight - Starting

t0

GAS GENERATOR ROTATION SPEED - AEO max take-off (< 5 min) - AEO max continuous (98 % N1) - OEI (< 2 min 30 sec) - OEI inter contingency (unlimited) - OEI super contingency (according to version)

GAS TEMPERATURE - Max during start - Max (t < 10 sec.) - Max OEI (2 min 30) - Max take-off

OPERATING LIMITATIONS (1) For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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OPERATING LIMITATIONS (2) Torque The torque limit is imposed by the aircraft transmission. The max torque limits are given for steady power settings and for transitory overtorque in AEO and OEI modes.

Oil There are various limits associated with the oil system, e.g. consumption = 0.3 l/h ; max pressure 800 kPa (116 PSI) ; min pressure 130 kPa or 90 kPa according to version (18.85 PSI), max temperature 115 °C (239 °F).

Starting - shut-down There are many limits associated with engine starting : -

Min voltage before start (e.g. 25 V) Min voltage during start (e.g. 15 V) Start duration : between 25 and 30 sec Ventilation duration : < 15 sec Number of consecutive starts - according to version Waiting time after 3 start attempts (e.g. 20 min) Stabilisation time before shutdown : 60 sec Run-down time : > 30 sec from 30 % to 0 % N1.

Other limitations Max air tapping rate , electrical consumption, load factors, vibration, etc.




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Training Manual

TORQUE

STARTING - SHUT-DOWN

- Stabilised max torque - Transient max torque

- Electrical voltage - Number of consecutive starts - Stabilisation, run-down and ventilation times

MISCELLANEOUS

OIL

- Air bleed - Electrical consumption - Loads factors - Vibration

- Max consumption - Max pressure - Min pressure - Max temperature

OPERATING LIMITATIONS (2) For training purposes only © Copyright - TURBOMECA - 2000



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OPERATING PROCEDURES (1) The operating procedures are considered for training purposes only. Refer to the aircraft manual.

Ventilation - Control lever to "stop"

Pre-start checks - Inspections, checks…

- Cranking button "on" (and maintained). The engine accelerates without ignition and fuel : ventilation should not exceed 15 seconds.

Starting

Relight in flight

- Power "on"

- Procedure identical to start on ground.

- Control lever to "start position" - Start button pressed and held. The engine starts and accelerates. During start, check : N1, N2, t4, oil Pr and t°. At 45 % N1, release the "start button"

Note : Confirm shut-down before start attempt. Wait until N1 has decelerated.

- Control lever moved to "Flight". The engine accelerates up to nominal rotor speed.

Shut-down - Stabilisation - Control lever to "stop". The engine shuts down : check the rundown time.




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Training Manual

STARTING

SHUT-DOWN

90° 52° 5°

45°

RELIGHT IN FLIGHT

VENTILATION

START - SHUT-DOWN - VENTILATION - RELIGHT

OPERATING PROCEDURES (1) For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

OPERATING PROCEDURES (2) Flight

Training to engine failure

- Control lever in "flight" position. Automatic control : monitor engine parameters, especially the N1 indication.

This procedure must be carried out with a reduced helicopter mass, (refer to flight manual).

Engine failure (twin-engine) The engine remaining in operation supplies the power required, within its limitations (MCP : 2 min 30 sec).

Control system total failure The manual control procedure can be applied ("plus" and "minus" range) : close monitoring of parameters.




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Training Manual

ENGINE FAILURE (twin-engine)

FLIGHT

90° 52°

5°

45°

TRAINING TO ENGINE FAILURE

CONTROL SYSTEM TOTAL FAILURE

OPERATING PROCEDURES (2) For training purposes only © Copyright - TURBOMECA - 2000



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13 - VARIOUS ASPECTS OF MAINTENANCE - Maintenance concept .................................................... - TBOs and life limits....................................................... - Preventive maintenance ................................................ - "On-condition" monitoring .......................................... - Corrective maintenance ................................................ - Lubricants - Fuels - Materials ..................................... - Tooling ............................................................................ - Technical publications .................................................. - Product support ............................................................


13.2 13.4 13.6 13.8 13.10 13.12 13.14 13.16 13.22 to 13.23


VARIOUS ASPECTS OF MAINTENANCE

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MAINTENANCE CONCEPT Introduction

Second line maintenance (level "I") : engine maintenance in a workshop.

The engine is designed to have a high availability rate with reduced maintenance. The main aspects of the maintenance concept are the following : - Effective modularity

- Corrective maintenance : SRU and module removal and installation. Third line maintenance (level "H") : deep maintenance which involves module repairs. - Corrective maintenance : component replacement.

- Good accessibility

Fourth line maintenance (level "D") : overhaul and repair in specific workshop.

- Reduced removal and installation times - On-condition facility - Quick repair.

- Maintenance scheduled when the TBO is completed or when the life limits of some components are reached

Maintenance levels

- Corrective maintenance.

Four maintenance levels can be considered :

Other aspects of maintenance

First line maintenance (level "O") : engine installed in the aircraft.

Refer to the following pages.

- Scheduled and preventive maintenance • Checks and inspections • Life limit or time-ex removal.

Note : LRU - Line Replaceable Unit SRU - Shop Replaceable Unit.

- Corrective maintenance • Fault detection • Component replacement (LRU) • Check. For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

MAINTENANCE LEVELS

1st LINE MAINTENANCE (level "O") (engine installed on aircraft) - Scheduled or preventive maintenance - Corrective maintenance

2nd LINE MAINTENANCE (level "I") (engine removed) - Corrective maintenance (modules, SRU)

3rd LINE MAINTENANCE (level "H") (engine removed) - Deep maintenance

4th LINE MAINTENANCE (level "D") (engine removed in specific workshop) - Scheduled maintenance (overhaul, repair) - Corrective maintenance

MAINTENANCE CONCEPT For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

TBOs AND LIFE LIMITS Engine, module and accessory TBOs

TBO components

TBOs (operating Time Between Overhauls) are defined for the engine, the modules and the accessories. These TBOs, determined by tests and experience, are subject to an extension programme.

- Engine

Component life limits

- Modules - Certain accessories.

Life limited components

Certain components (mainly rotating parts such as compressor, turbines, injection wheel, flectors…) have a life limit which requires the part to be scrapped when the limit is reached.

- Axial and centrifugal compressors - Injection wheel - Turbines.

The life is measured in operating cycles.

Counting of hours and cycles A cycle is a clearly defined operating sequence. Cycle counting is effected either manually or automatically. The method of counting cycles and the various limits are described in Chapter 5 of the maintenance manual. A counting check (comparison between automatic counting and manual counting) is a procedure planned in the periodic maintenance. A simple check can be carried out by comparing the two engine readings for a given period of operation.




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Training Manual

TBO

COUNTING

- Engine - Modules - Accessories

- Manual counting - Automatic counting - Counting check

CYCLE COUNTER

LIFE LIMITS Cycles for : - Compressors - Turbines - Injection wheel AUTOMATIC COUNTING

TBOs AND LIFE LIMITS For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

PREVENTIVE MAINTENANCE Preventive maintenance includes the procedures which must be systematically carried out.

Main inspection points of preventive maintenance - Visual inspections

Servicing inspections

- Magnetic plug and filter inspection

- Inspection before the first flight of the day

- Oil sampling for analysis

- Inspection after the last flight of the day.

- Level checks

(Refer to maintenance manual).

- Compressor cleaning (according to operating conditions)

Periodic inspections

- Operating checks and ground run test

- These procedures can be "blocked" (at fixed intervals for all the procedures) or staggered (each procedure is distributed over a period of time to reduce the turnaround time while still respecting the intervals)

- Cycle counting check - Static droop check - Run down check.

- 100 hour, 500 hour, 1500 hour or calendar inspections (18 months) - Special inspections : • Particular inspections • Inspections according to airworthiness.




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Training Manual SERVICING INSPECTIONS

PERIODIC INSPECTIONS - Procedure "blocked" or "staggered" - 100 hour inspection - 500 hour, 1500 hour or calendar inspections (18 months) - Special inspections

- Inspection "after the last flight of the day" - Inspection "before the first flight of the day"

MAIN INSPECTION POINTS - Visual checks : air intake, compressor, exhaust, turbine, casings, attachments, pipes, wiring, controls - Inspection of filters : oil filter, fuel filter, air tapping unions and jets - Inspection of magnetic plugs - Oil sampling (for analysis) - Oil level (and replenishment if required) - Compressor cleaning (depending on operating conditions) - Ground run test - Static droop test - Run down check - Cycle counting check

PREVENTIVE MAINTENANCE For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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ON-CONDITION MONITORING When applying on-condition maintenance, the maintenance procedures are carried out according to the condition of engine components. It requires a monitoring which includes appropriate procedures studied during the engine design.

Objectives of on-condition monitoring The objective is to increase safety and to reduce maintenance costs. This is achieved because the monitoring ensures an early diagnosis of defects which could have seri ous consequences ; on the other hand, monitoring avoids unnecessary maintenance tasks.

On-condition monitoring resources On-condition monitoring implies an appropriate design of the engine which allows the use of monitoring tools.

- Lubricating oil check : various methods are used to check for the contamination of the oil (magnetic plugs, strainers, sampling). Samples of oil are taken at regular intervals and the samples are analysed to measure the contamination and anticipate incipient failures (analysis by magnetoscopy, ferrography, spectrometric oil analysis) - Vibration level check : the vibration level of the rotating assemblies gives an indication of the engine condition. Sensors installed at given points are used to measure the vibration level. This type of check is carried out during periodic inspections or according to engine condition - Visual inspection : conventional visual inspections are also considered for on-condition monitoring (air intake inspection , exhaust pipe inspection , exhaust and engine external inspections…).

The following procedures are considered : - Borescopic inspection : this permits inspection of internal parts which are not accessible without disassembly : compressor, combustion chamber and turbine. A special tool is used to allow direct visual inspection of the parts




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Training Manual

OBJECTIVES OF ON-CONDITION MONITORING - To increase safety - To reduce maintenance costs

BORESCOPIC INSPECTION

VIBRATION CHECK

STRAINERS

MAGNETIC PLUGS

VISUAL INSPECTION

OIL SAMPLING

ON-CONDITION MONITORING For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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CORRECTIVE MAINTENANCE The objective of corrective maintenance is to put the engine back into normal service as soon as possible. Corrective maintenance includes all procedures which must be carried out when required (failure, defect…). It implies general and particular activities.

Corrective maintenance main tasks - Removal and installation : removal and installation of the complete power plant, of the accessories and of the modules and of some engine components as required. Note : Assembly and disassembly of the engine is dealt with in general overhaul and repair - Functional checks : functional check of systems, and accessories… - Condition checks - Adjustments - Miscellaneous procedures : cleaning, storage… - Repairing (components may be repairable or consumable) - Fault finding (refer to chapter 15 "FAULT ANALYSIS AND TROUBLE SHOOTING") - Particular instructions : for example, procedures in the event of oil contamination, surge, heavy landing, handling accident, lightning strike.




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Training Manual

OBJECTIVES OF CORRECTIVE MAINTENANCE - To put the engine back into normal service as soon as possible

CORRECTIVE MAINTENANCE MAIN TASKS - Removal and installation - Functional and condition checks - Adjustments - Miscellaneous procedures (cleaning, storage ...) - Repairing (consumable or repairable components) - Fault finding - Particular instructions

CORRECTIVE MAINTENANCE For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

LUBRICANTS - FUELS - MATERIALS This part deals with information on materials used : fuels, lubricants, greases, fluids.

Lubricants

The maintenance manual (chapter 71.00.02) contains tables indicating the fuel types with the corresponding US, UK, NATO and French specifications. Two types of fuel can be considered :

The engine manufacturer recommends the use of synthetic oils which keep their lubricating properties over a wide temperature range and have a longer operating life. Medium viscosity oils (5 cSt) are more particularly recommended but other types (3 to 3.9 cSt) may be used as an alternative. The maintenance manual (chapter 71.00.02) contains specification tables and precautions.

- The "normal fuels" which can be used without restriction in all the operating envelope - The "emergency fuels" (or replacement fuels) which may be used, but with particular restrictions and for a limited time in order not to affect the engine TBO.

Materials Various products are used for engine parts maintenance.

We shall remind you here that the mixture of oils of different types is not recommended. Therefore the system should be flushed when the oil specification is changed.

For example graphite grease, molybdenum disulphide for the installation of parts, cleaning and inhibiting products.

Fuels

The various products must be used carefully, for instance use of trichlorethylene on titanium alloy parts is forbidden.

The quality of the fuel is essential for the correct operation of the engine. It is particularly important to ensure a proper fuel supply : specification, water content, purity…




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Training Manual

LUBRICANTS (maintenance manual, chapter 71.00.02) - Normal lubricants : medium viscosity synthetic oils - "Emergency" lubricants : medium and low viscosity oils - No mixture of oils of different specifications - Flushing of the system when the oil specification is changed

FUELS (maintenance manual, chapter 71.00.02)

MATERIALS - Part installation : graphite grease, molybdenum disulphide…

- Normal fuels : (without restriction) - "Emergency" fuels (with particular restrictions : operating times, additives…)

- Cleaning : water, fuel, alcohol, detergent… - Storage : waterproof product

LUBRICANTS - FUELS - MATERIALS For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

TOOLING This part deals with information on maintenance tools.

- Packing equipment (e.g. : wooden or metal container)

Tools

- Tools used for removal and installation (e.g. : extractors, wrenches, supports for module removal and installation)

Maintenance requires certain tools, but in addition to the normal standard tools, a certain number of special tools and test equipment can be used. During a training course, these tools are used to carry out practical work : current maintenance and modular maintenance tools. The tools are described in an illustrated catalogue and also in the maintenance manual. In the catalogue, tools can be identified either by the function, or by the aspect or the reference.

Tool classification

- Tools for miscellaneous procedures and checking equipment : • Oil drain • Compressor washing • Vibration check • Borescopic inspection • Pressure transmitter inspection (torquemeter, fuel, oil) • Ignition system inspection • Harness inspection • Electrical measurement • Fuel injection system permeability.

We can distinguish : - Tools used for standard practices (e.g. : thread insert replacement)

Note : The tools are to ISO standard.

- Blanking devices - Handling equipment (e.g. : lifting device, engine support, transport trolley)




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Training Manual

TOOLS

TOOL CLASSIFICATION

- Normal - Specific

- Standard practices - Blanking devices - Handling equipment - Packing equipment - Removal and installation - Checking procedures: • Oil drain • Compressor washing • Vibration check • Borescopic inspection • Pressure transmitter inspection • Ignition system inspection • Harness inspection • Electrical measurement • Fuel injection system permeability

CATALOGUE Identification by : - Function - Picture - Reference

TOOLING For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

TECHNICAL PUBLICATIONS - GENERAL This part deals with the engine technical documentation.

Operation documents The operation documents are :

- The general overhaul and repair documents : • Overhaul manual • Standard practices manual • Work specification.

- The control documents (e.g. : flight manual)

- The deep maintenance documents (specific manual).

- The management documents : • Flight log book • Engine log book (records and provides information on the engine status).

Identification documents

Maintenance documents - The current maintenance documents are the following : • Maintenance manual (describes the engine and its systems and all the maintenance procedures) • Service bulletins (approved by the authorities, and issued to inform the operators of a modification or an instruction which affects the operational aspects) • Service letters (letter sent to inform the operator of certain instructions related to the operation of the engine) • Modification index


The identification documents are : - The current maintenance documents : • Spare parts catalogue (list and reference of all the spare parts) • Special tool catalogue (tool designations and references). - Overhaul and repair documents : • Illustrated parts catalogue (illustrates in detail all the engine and accessory parts ; only used for general overhaul) • Descriptive list and drawings.

Note : Before all maintenance procedures : - Refer to official documentation - Use the documentation "in a rational way" - Make sure that documentation is up-to-date.



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Training Manual

DOCUMENTS

OPERATION

MAINTENANCE

Current maintenance

Control

Management

Example : Flight manual

Example : - Engine log book

CURRENT MAINTENANCE

- Maintenance manual - Service bulletins and letters - Modification index

IDENTIFICATION

Overhaul repair

- Spare parts catalogue - Special tool catalogue

GENERAL OVERHAUL REPAIR

- Overhaul manual - Standard practices manual - Work specification

- Illustrated parts catalogue - Descriptive list and drawings

DEEP MAINTENANCE

- Specific manual

TECHNICAL PUBLICATIONS For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

TECHNICAL PUBLICATIONS MAINTENANCE MANUAL It describes the engine and its systems and all the maintenance procedures.

Layout This document has been compiled according to the requirements in the American standard "A.T.A. 100" as follows :

Installation .............................................from 401 to 499 Cleaning .................................................from 601 to 699 Replacement ..........................................from 701 to 799 Check, inspection...................................from 801 to 899 Servicing ............................................from 1101 to 1199 Storage ...............................................from 1201 to 1299 Tests ...................................................from 1301 to 1399

Layout of a chapter

CHAP

DESIGNATION

00 05 26 70 71 72 73 74 75 77 78 79 80 83

Introduction Time Between Overhauls and life limits Fire protection system Standard practices Power plant Turboshaft engine Fuel system Ignition system Air system Engine indicating Exhaust system Oil system Starting Accessory gear-box

0. 1. 2. 3. 4.

5. 6. 7.

Page numbering (ATA 100) Description and operation ............................from 1 to 99 Fault analysis .........................................from 101 to 199 Special procedures .................................from 201 to 299 Removal .................................................from 301 to 399


8.

Introduction General Purpose Complementary documentation Breakdown A. Chapters B. Page numbering C. Item numbering D. Illustration Effectivity Revisions A. Normal revisions B. Temporary revisions Use of this manual A. Systematic maintenance operation B. Optional maintenance operations C. Replacement of modules List of abbreviations



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Training Manual

OBJECTIVE

LAYOUT

- Description / operation of the engine and its systems - Maintenance procedures

- Chapters - Sub-chapters - Paragraphs

CONSULTATION

NUMBERING

- Consultation method - Up-dating

- Gives the subject treated by the page

TECHNICAL PUBLICATIONS - MAINTENANCE MANUAL For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

TECHNICAL PUBLICATIONS - TURBOMECA ENGINE LOG BOOK Function

- Section C : accessory replacement : when an accessory is replaced, the details should be entered on the right hand page.

This log book is used for : - Recording all information about the engine, the modules and the accessories, including the hours and cycles used and work carried out

- Section D : TBO : the TBO of a replacement module should be recorded here

- Recording the basic modification standard of the engine.

- Section E : • "Daily" column : record the daily hours and cycles

Contents

• "Total since new" column : record the accumulated hours and cycles

- Test bed results sheet - Section A : test certificate and record of modifications embodied on non modular parts

• "Total since start of life" column : record the accumulated hours and cycles since the last modular rebuild.

- Section B : record of modules Note : After changing a module the "total since start of life" column should be returned to zero.

- Section C : record of equipment - Section D : availability state - Section E : operation, maintenance and servicing - Maintenance and accessory log cards.

Use of the log-book - Test bed results sheet and section A : completed in the factory, may not be modified by the operator - Section B : when a module is replaced, record the reference number, the serial number and the date on the right hand page


• "Observations" column : Record : - The type of work carried out - The reference, serial N°, hours/cycles and reason for change of module or accessory replaced - The embodiment of a modification. • Module/Component log card : record fitting/removal details.



ARRIEL 1

Training Manual SECTION B R

Désignation / Identity

Fabricant - Référence Manufacturer - Reference

N° Série Serial No

Date Signature

R


Fabricant - Référence Manufacturer - Reference


Date Signature

SECTION C R


Fabricant Manufacturer

Référence / Reference Fabric. / Manuf. Motorist. / Eng. M.


Tot. h. moteur / Total eng. hrs Prévi. dépose Pose / Fitting Forecast rmv.

h équipt pose Accy hrs when fitted

Date Signature

SECTION D

1 - POTENTIEL / T.B.O. Moteur non modulaire ou modules / Nonmodular engine or modules

Total h

Effectué Consumed h

2 - VIE LIMITE / LIVE LIMIT Disponible Available h

Pièces / Parts

Total Cycles

Effectué Consumed Cycles

Disponible To be run Cycles

Boîte accessoires Accessory gearbox Compresseur axial Axial compressor

Roue compresseur axial Axial compressor wheel

SECTION E FONCTIONNEMENT / TIME RUN Total depuis neuf Total depuis état de disp. Total since new Total since stat. of life Cycles Cycles Cycles H H Gas T.L. Gas T.L. Gas T.L. Gen P.T. Gen P.T. Gen P.T.

Journalier Daily Date H

Observations - Travaux effectués - Signature Observations - Works carried out - Signature

TECHNICAL PUBLICATIONS - TURBOMECA ENGINE LOG BOOK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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PRODUCT SUPPORT General TURBOMECA provides the operator with the training and the assistance required to maintain the product in good operating condition.

Main aspects of the support The support covers the following fields : - Training - Technical documentation - Spare part provision - Technical assistance - Engine overhaul and repair - Contracts.

Subsidiaries and support centres Subsidiaries and support centres have been set up to provide a world wide support network.




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Training Manual

TRAINING

TECHNICAL DOCUMENTATION

SUBSIDIARIES AND SUPPORT CENTRES

CONTRACTS

SPARE PART PROVISION

TECHNICAL ASSISTANCE

PRODUCT SUPPORT For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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14 - MAINTENANCE PROCEDURES - General .......................................................................... 14.2 - Inspection and check procedures ................................ 14.4 - Removal and installation procedures ......................... 14.52 - Deep maintenance.......................................................... 14.62 - Repair and overhaul ..................................................... 14.64 to 14.65



MAINTENANCE PROCEDURES

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MAINTENANCE PROCEDURES - GENERAL This part is an introduction to the different maintenance procedures, which are described in the following pages for training purposes only.

- Permeability check

These procedures are dealt with in discussion and practical work during a training course.

- Removal and installation of the accessories

Procedures described

- Repair, general overhaul.

- Engine removal and installation

- Module removal and installation

- Standard practices - Cautions (Cautions, Warning) - Storage

Note : Refer to the maintenance manual and ensure that it is up to date before carrying out any maintenance procedure.

- Compressor washing - Oil checks - Miscellaneous checks - Borescopic inspection - Axial compressor inspection - Operating checks - Vibration check - Electrical harness check.




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Training Manual

PROCEDURES

LISTS OF PROCEDURES

- Definition - Instructions and operating modes

- Standard practices - Cautions - Storage - Washing - Miscellaneous checks - Miscellaneous procedures - Removal, installation - Repair - Adjustments

Note : Refer to the maintenance manual before carrying out any maintenance procedure.

MAINTENANCE PROCEDURES - GENERAL For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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STANDARD PRACTICES General "Standard practices" are all the common procedures and practices, required for the maintenance and repair of engines. These "standard practices" are dealt with in one chapter of the maintenance manual (chapter 70). They are also dealt with in a specific document, called The Standard Practices Manual, mainly used by repairers.

Main practices Standard practices mainly deal with : - Torque loading - O'ring seal installation - Locking of assemblies - Pipe and union assembly - Thread insert replacement - Magnetic seal replacement - Application of miscellaneous products (loctite, graphite grease…) - Repair techniques (exhaust pipe welding, crack stop drilling…) - Installation of electrical connectors - Check and inspection (ex. : fuel/oil dilution check). For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

O'RING SEAL INSTALLATION

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TORQUE LOADING (torque wrench) STANDARD PRACTICES - Manual - Chapter 70 of the maintenance manual

LOCKING OF ASSEMBLIES

THREAD INSERT REPLACEMENT

PIPE AND UNION ASSEMBLY

STANDARD PRACTICES For training purposes only © Copyright - TURBOMECA - 2000



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ADVISORY NOTICES Three types of advisory notice are used in the technical publication :

NOTE : take the oil sample before carrying out any replenishment.

- WARNING

List of the main notices

- CAUTION

WARNING :

- NOTE.

- Toxicity of engine oil, cleaning products and extinguishing products

Interpretation

- Eye protection

WARNING : warns the reader of the possibility of physical harm (e.g. : wounding, intoxication, electrocution).

- Fire risk

CAUTION : warns the reader of the possibility of damaging the engine or tooling.

CAUTION :

NOTE : gives the reader advice on how best to carry out a task.

- Electrical discharge from HE ignition unit.

- Use of the correct tool - Use of certain products - Weak points of the engine or tools

Examples WARNING : do not breath the oil fumes. Do not leave oil in contact with the skin. CAUTION : if the flush is being carried out because of metal particles in the oil system, change the filter and thoroughly clean the tank.

- Tightening torques. NOTE : - Oil analysis - Cycle counting - Engine storage - Parameter measuring.




ARRIEL 1

Training Manual

WARNING (physical harm)

- Toxicity of engine oil and vapours - Toxicity of cleaning products - Toxicity of extinguishing products - Eye protection - Fire risk - Electrical discharge from HE ignition unit : - electrocution - risks with use in an inflammable atmosphere

CAUTION (possibility of damage)

- Titanium part cleaning - Scrapping of O'ring seals - Use of the correct cleaning products - Engine cooling - Engine cleaning after use of extinguishing product - Orifice protection during removal - Borescope fragility - Tightening torque

NOTE (advice)

- Oil analysis - Cycle counting - Installation of O'ring seals - Engine storage - Insulation measurements - Procedural change with modification

ADVISORY NOTICES For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

STORAGE General When an engine is not used for a long time, it must be protected against corrosive agents. The most efficient protection consists of : - Washing and protecting the air path by spraying a specific product - Housing the engine in a waterproof metal container with dessicant bags. If there is no container, the engine can be housed in a water and vapour proof cover with desiccant bags.

- "Short term" storage : procedure which protects the engine for a duration of less than 3 months if the engine is not installed in the helicopter. If the engine is installed in the helicopter : • When the engine is not used for less than 7 days, install the air intake and exhaust blanking devices and close the cowlings • When the engine is not used between 7 days and 6 months, drain and replace the oil, do a 5' ground run check every 7 days • When the engine is not used for more than 6 months, remove the engine and do the "long term" storage procedure.

Type of storage - "Long term" storage : procedure which protects the engine for a duration of more than 3 months if the engine is not installed in the helicopter. The engine is then inhibited in the package (in non sealed case or in metal container)


Note : Refer to maintenance manual for storage limits (eg. : 10 years in metal container).



Training Manual

GENERAL

ARRIEL 1 TYPE OF STORAGE

- Protection against corrosive agents - Cleaning, internal and external protection

- "Long term" : duration more than 3 months (storage in a container) - "Short term" : duration less than 3 months (protection cover)

PROCEDURES - For engine installed in aircraft (less than 7 days or between 7 days and 6 months) - For uninstalled engines (3 months and more than 3 months) - Internal and external protection - System protection - Inhibiting products - Blanking devices

PACKAGE - In non sealed case - In metal container : procedure, storage and periodic inspections Note : Package of engine, modules and accessories

STORAGE For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

CLEANING AND PROTECTION General Given procedures are applied to clean and protect the engine.

Main procedures - Internal cleaning and protection (rinsing, washing, cleaning, protection : refer to compressor washing) - External cleaning and protection - Procedure after usage of extinguisher - Procedure to protect the equipment (ex. : water in fuel…).

Note : Follow the instructions for the use of the cleaning products. Refer to maintenance manual, chapter 71.




Training Manual

ARRIEL 1

GENERAL - Cleaning - Protection

PROCEDURES - For internal parts (refer to compressor washing) - For external parts - For equipment

NOTES - Precautions - Ref : Maintenance manual chap. 71

CLEANING AND PROTECTION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

COMPRESSOR WASH General

Procedures

Compressor washing avoids dirt accumulation and corrosion in the air path, particularly the compressor.

Compressor washing mainly consists of spraying a suitable product in the air intake during one or several ventilation sequences (water, Ardrox…).

Types of treatment - Washing and/or rinsing : removal of corrosive deposits (particularly salt deposits)

Note : Many aircraft are fitted with a compressor washing system. Washing and cleaning during a ventilation is considered the most efficient.

- Cleaning : removal of deposits likely to accumulate on the internal parts - Protection : protection of surfaces against corrosion. Frequencies - Washing : frequently in salt laden atmosphere - Cleaning : periodic inspection before storage, if necessary - Protection : before storage or in case of long grounding.

Note : Frequencies depend on operating conditions.




Training Manual

ARRIEL 1

GENERAL

TYPES OF TREATEMENT

- To avoid dirt accumulation and corrosion in the air path, particularly the compressor - Preventive operation

- Washing and / or rinsing : removal of corrosive deposits (particularly salt deposits) - Cleaning : removal of deposits likely to harm the internal parts - Protection : protection of surfaces against corrosion

FREQUENCIES PROCEDURES

- Washing : frequently in salt laden atmosphere - Cleaning : at periodic inspection before storage, if necessary - Protection : before storage or in case of long grounding

- Spraying a suitable product in the air intake during one or several sequences - Spraying device - Products (water, ardrox)

COMPRESSOR WASH For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

OIL SYSTEM SERVICING This part summarizes the maintenance procedures for the oil system.

- Sampling procedure - Word definition (ppm, concentration, contamination speed, thresholds…)

Particular instructions Maintenance manual instructions must be followed in the following cases :

- Result interpretation (warning threshold and immediate stop table).

- Oil specification change

Oil change

- Mixing with a product which is not in conformity with oil specification

- Drain conditions (blockage, particles, before removal) - Drain procedure (engine through magnetic plugs, cooling unit and tank according to aircraft manufacturer's procedure).

- Oil life limitation - Oil filter blockage

Oil filling

- Dilution.

- Aircraft manufacturer's procedure.

Particle sampling

Oil system flushing - Particle sampling procedure with magnetic plugs - Particle interpretation - Particle analysis.

Spectrometric oil analysis

- Conditions (oil specification change, contamination, life limitation…) - Procedure (draining, filling, ground run, draining, filter inspection, final filling).

- Purpose of the spectrometric analysis - Sampling frequency




Training Manual

ARRIEL 1 SPECTROMETRIC OIL ANALYSIS

PARTICULAR INSTRUCTIONS - Oil specification change - Mixing - Life limitation - Filter blockage - Oil dilution

- Purpose - Frequency - Procedure - Definition - Interpretation

OIL CHANGE - Conditions - Procedure

PARTICLE SAMPLING - Procedure - Interpretation - Analysis

OIL SYSTEM FLUSHING - Conditions - Procedure

OIL FILLING - Tank (aircraft manufacturer's procedure)

OIL SYSTEM SERVICING For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

MISCELLANEOUS PROCEDURES This part only mentions procedures which are part of the maintenance activity.

Introduction into service

- Exceeding of limits : particular instructions in case of temperature, torque and speed exceedance, and in case of engine flame out, compressor surge - Heavy landing

The introduction into service includes :

- Damage during transport.

- The preparation of an engine delivered in a wooden case

Treatment after use of extinguishers - The preparation of an engine delivered in a metal container - Installation in the aircraft - A ground run check.

The treatment required after use of a fire extinguisher or an accidental operation of the extinguishing system, minimises corrosion by extinguishing products. The treatment is different according to the conditions of the extinguisher use and to the extinguishing products (CO2, foam, powder, halon…).

Adjustments The engine is designed to require no current maintenance adjustments. Refer to corresponding pages and to maintenance manual for more details.

Particular instructions - Fuel : follow particular instructions in case of use of an alternative fuel and additives and in case of filter blockage - Foreign Object Damage (FOD) : procedure according to the nature of the body ingested (direct visual inspection, borescopic inspection, vibration check) For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

INTRODUCTION INTO SERVICE

ADJUSTMENTS

- Preparation of an engine delivered in a wooden case - Preparation of an engine delivered in a metal container - Ground run check

- The engine is designed not to require current maintenance adjustments. (refer to maintenance manual)

TREATMENT AFTER USE OF EXTINGUISHERS PARTICULAR INSTRUCTIONS

- Normal or accidental use - Treatment to reduce corrosion by extinguishing products - Treatment according to use conditions (fire or accidental use) and to the extinguishing product (CO2, foam, powder, halon...)

- Fuel - Foreign Object Damage - Exceeding of limits - Heavy landing - Damage during transport

MISCELLANEOUS PROCEDURES For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

BORESCOPIC INSPECTION General Borescopic inspection allows the inspection of the internal parts which are not accessible without disassembly. This type of inspection uses a special tool which allows a direct visual inspection of the parts. Borescopic inspection can be carried out with the engine in or out of the helicopter, and on removed modules.

Combustion chamber borescopic inspection To do this inspection, it is necessary to remove an igniter plug. The combustion chamber inspection is done by entering the borescope through the igniter plug orifices

Borescopic inspection of the gas generator turbine It allows the visual inspection of the nozzle guide vane and the wheel (blades, blade roots...). The inspection is carried out using a flexible borescope and a guide in one of the igniter plug orifices.




Training Manual

ARRIEL 1

Combustion chamber and turbine - Inspection of the internal parts which are not accessible without disassembly - Use of special tools - Borescopic inspection with the engine in or out of the helicopter

- Rotation of the N1 rotating assembly through one of the accessory drives or the compressor - Rotation of the N2 rotating assembly either through the rotor (engine on aircraft) or through the main power drive (engine removed)

BORESCOPIC INSPECTION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

AXIAL COMPRESSOR INSPECTION Function

Criteria

This check permits the detection of dents, cracks and erosion.

The maintenance manual details the procedure to be followed, the number of dents permitted, their max depth and the max permitted erosion value. No cracks permitted.

Conditions This check can be carried out with the engine installed or uninstalled, and on a removed module.

Refer also to the maintenance manual for the rework procedure of the axial compressor 1st stage blades.

Procedures - Visual inspection of the blades - Erosion inspection using a gauge.

Visual inspection The blades must be inspected for cracks, folding, pitting, dents and nicks.

Erosion inspection This is carried out by placing the template on the inlet cone, with the indicator plate butted up against the blade root. The calibrated gauge is then introduced between blade and template to measure the erosion.




ARRIEL 1

Training Manual

GAUGE

L Max limit sector D = 3 mm

D

Max limit sector A = 1 mm

2 mm (0.0787 inch) A B C D

TEMPLATE

3 mm (0.1181 inch)

EROSION INSPECTION

VISUAL INSPECTION

AXIAL COMPRESSOR INSPECTION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

FREEWHEEL CHECK On single engine version :

Function To check the oil level (single engine).

Conditions This check can be carried out engine installed or removed from the helicopter.

Procedure The free wheel is equipped with two plugs, for oil level check and oil draining. The filling port must be correctly positioned. On some versions, the oil supply is assured by means of a lubricating jet located inside the accessory gearbox.




ARRIEL 1

Training Manual

OIL LEVEL CHECK POSITION :2 O'CLOCK OIL FILLING PORT

FREEWHEEL CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

CHECK OF INJECTION FUEL INLET UNION Purpose To check for leaks of fuel or P2 air.

Conditions This check is carried out in the aircraft during a ground run.

Procedure With the blanking screw removed and the engine running there must be no leaks from the orifice. In the event of leaks the seals must be replaced and a further check carried out.




ARRIEL 1

Training Manual

"O" RING

COPPER SEAL

LEAK CHECK POINT (normally blanked)

CHECK OF INJECTION FUEL INLET UNION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

VIBRATION CHECK Conditions The vibration check is systematically made at regular intervals and in the following cases : - After any failure due to an excessive vibration level - In case of doubt about the engine vibration level - After a modular maintenance operation.

Procedure This check is carried out with a vibration sensor fixed on the engine (on the HE unit support or on the rear flange of the turbine casing). The accelerometer measures the vibration generated by the gas generator and the power turbine. There are many vibration checking sets (refer to the maintenance manual).




Training Manual

ARRIEL 1 VIBRATION SENSOR

REAR SENSOR BRACKET (on the HE unit support or on the rear flange of the turbine casing)

Examples of a vibration measurement system. (Other systems can be used)

VIBRATION TEST SET

VIBRATION CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

ENGINE POWER CHECK Conditions An engine power check can be carried out in flight by recording certain parameters and plotting them on a graph. For further details see the flight manual.




ARRIEL 1

Training Manual

GOOD

Tq %

BAD

N1

NR

Zp

t0

Example of a diagram with an operating point shown with dotted lines

ENGINE POWER CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

TORQUE TRANSMITTER AND LOW OIL PRESSURE SWITCH CHECK Purpose To check the operation of the torque transmitter and the low oil pressure switch.

Conditions The component to be checked must be removed from the engine.

Procedure The check can be carried out either using the Turbomeca test set or a Barfield pump. Torque transmitter : the pressure corresponding to 100 % torque is written on the module 5 log card. With the transmitter fitted on the test set the pressure is raised to the log card figure and the indication can then be checked and adjusted. Low oil pressure switch : with the unit fitted on the test set the pressure can be increased & decreased to check at what pressure the switch makes & breaks.




ARRIEL 1

Training Manual

DIGITAL INDICATOR

REFERENCE CAPSULE

COCK

TORQUE TRANSMITTER

CONTROL

BARFIELD PUMP TEST SET LOW OIL PRESSURE SWITCH

TORQUE TRANSMITTER AND LOW OIL PRESSURE SWITCH CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

IGNITION SYSTEM CHECK Purpose To check the operation of the engine ignition system.

Conditions This check can be carried out with the engine installed or uninstalled. The test set requires a 28 volt supply.

Procedure The test set is connected to the HE unit input connector. Selection of "ignition" on the test set supplies the HE unit, a light indicates a complete circuit and the igniters operate.

Note : The same test set can be used for testing the start injector electro-valve.




ARRIEL 1

Training Manual

TO H.E. IGNITION UNIT

28 VDC SUPPLY

TEST SET

IGNITION SYSTEM CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

OVERSPEED SYSTEM CHECK Purpose To confirm the integrity of the overspeed system.

Conditions The check can be carried out engine installed or uninstalled, tacho box installed or uninstalled.

Procedure With the test set supplied with 28 V and connected to the tachometer box signals of overspeed frequency can be supplied to the box to check its operation.

Note : The same test set can be used to check insulation and resistance of the overspeed pick-up probe.




ARRIEL 1

Training Manual

TACHOMETER BOX

TEST

TEST SET

OVERSPEED SYSTEM CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

COMPRESSOR BLEED VALVE OPERATION CHECK Purpose To check that the bleed valve operates at the correct RPM.

Conditions This check can only be carried out with the engine running at high RPM, perhaps necessitating a take-off.

Procedure For the electro pneumatic valve check that the N1 threshold (opening and closing) is correct. For pneumatic valves, the threshold is function of altitude and atmospheric temperature. It is necessary to refer to a graph in the maintenance manual.




ARRIEL 1

Training Manual

N1

Z = 2000 m Z=0

t0

Example of curve showing the N1 threshold as a function of t0 and Z. (pneumatic bleed valve)

COMPRESSOR BLEED VALVE OPERATION CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

OIL PRESSURE CHECK Purpose To accurately check the engine oil pressure in case of doubt, after a module change or after assembling a repaired or overhauled engine.

Conditions Engine installed & running, the pressure is checked at 2 points using a calibrated pressure measuring tool.

Procedure Connect the measuring tool to the test point, start the engine and allow it to warm up to the normal operating temperature. Set the RPM at 85 % then read the temperature & pressure. Plot the temperature & pressure on the graph in the maintenance manual to see if the pressure is within tolerance.

Note : There are several graphs to allow for different oil viscosities.




ARRIEL 1

Training Manual

P

t°

Example of graph to check oil pressure for a given oil specification on a given tapping point.

OIL PRESSURE CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

START INJECTOR AND IGNITER PLUG PENETRATION CHECK Conditions In the event of starting problems on replacement of a plug or injector the penetration of the plug and injector must be calculated and adjusted using spacers and seals.

Procedure It is necessary to measure the length under the head of the injector and igniter and then measure the distance from the turbine casing face to the mixer unit, using a special gauge supplied by Turbomeca. Using the figures thus obtained, and the calculation table in the maintenance manual, the thickness and quantity of spacers and seals can be calculated.

Note : There must always be a seal against the face of the injector/igniter and against the face of the turbine casing.




ARRIEL 1

Training Manual

L C

X

e

START INJECTOR

COMBUSTION CHAMBER

e' X'

IGNITER PLUG

C'

GAUGE

L'

MEASUREMENTS OF THE INJECTORS AND IGNITER PLUGS PENETRATION IN THE COMBUSTION CHAMBER

START INJECTOR AND IGNITER PLUG PENETRATION CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

PERMEABILITY CHECK Conditions A permeability check of the fuel injection wheel must be carried out during periodic servicing. It may also be carried out in case of suspected problems.

Procedure The permeability test tool is connected to the injection wheel inlet union ; it is then filled to the top with water. After opening the cock at the inlet to the engine the time taken for the water level to pass between the two marks A and B on the tube is measured. A table in the maintenance manual shows the action to be taken according to the time recorded, e.g. t < 8 sec. - next check in 450 hours. t > 11 sec. - carry out wheel cleaning procedure.




ARRIEL 1

Training Manual

FUNNEL A MEASUREMENT OF FLOWING TIME BETWEEN A AND B B

COCK

INLET UNION

PERMEABILITY CHECK For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

STATIC DROOP CHECK AND ADJUSTMENT This is mandatory check in the event of an anomaly such as :

It is particularly important to use high precision digital indicators for the readings during the check.

- drift of max N1 Note : Any adjustment of the temperature bulb must be recorded in the engine log book to ensure that the maximum adjustment limit is not exceeded.

- drift of NR - N1 difference between 2 engines.

Procedure The procedure is carried out with the engine running on ground and is defined in the Maintenance Manual. This check verifies the relationship between N1, the anticipator angle at min. pitch end the NR. The procedure then determines the necessary action. This may require adjustment of the temperature compensating bulb or its replacement if the adjustment limit is reached.




ARRIEL 1

Training Manual

N1 % 89

87

85

83 82.3

22°

82 81.1

81

79

77 B = 0°

B = 10°

B = 20°

B = 30°

75 322

325

330

335

340

BEFORE TEMPERATURE COMPENSATOR ADJUSTMENT

345

350 346.2 347.7

355

358

NR min rpm

AFTER TEMPERATURE COMPENSATOR ADJUSTMENT

STATIC DROOP CHECK & ADJUSTMENT For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

CHECK OF NR AND OF N1 MATCHING This check verifies the instrumentation and the adjustment of the components of the fuel flow control system. The check procedure is defined in the Flight Manual.

Note : It is particularly important to use high precision digital indicators.


Any anomaly will be either an indication anomaly (indication of NR, N1 or torque) or incorrectly rigged controls e.g. anticipator or an anomaly in the F.C.U. (temperature compensation bulb). Normally the first action to take is to carry out a static droop check.



ARRIEL 1

Training Manual

TEMPERATURE COMPENSATING CAPSULE

N1

NR

N1

CHECK OF NR AND OF N1 MATCHING For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

CHECK OF MAX. N1 The max. N1 check ensures that the maximum engine power is available.

Note : This check must be carried out using very accurate instruments such as digital RPM indicators.

The check procedure is described in the Flight Manual. Generally the check will show, according to the engine type : - Either that the engine reaches the max N1 stop - Or that the stop is beyond the normal max N1. This check may identify an anomaly such as fuel system blockage, leak in the fuel system, drift at the fuel control caused by the temperature compensator.




ARRIEL 1

Training Manual

TEMPERATURE COMPENSATING CAPSULE (PRE-MOD TU183)

MARK

BIMETALLIC CORRECTOR (POST-MOD TU183) TEMPERATURE CAPSULE ADJUSTING SCREW (ADJUSTMENT, IF NECESSARY)

N1 max % Correct adjustment range

104,8

103,8

Fuel temperature °C -50

-40

-30

-20

-10

0

10

20

30

40

50

FCU SEEN FROM THE FRONT

CHECK OF MAX N1 For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

CYCLE COUNTING Cycle counting enables the calculation of usage of life limited parts such as compressors, injection wheel and turbine wheels.

Power turbine cycle

Two types of cycles must be counted : gas generator cycles and power turbine cycles.

Refer to the maintenance manual, chapter 5 for full details of the cycle counting including the exclusions and obligations.

For the power turbine one flight equals one cycle.

Gas generator cycles There are two formulas which can be used, the recommended method and the lump method. The recommended method takes into account the max N1 (K1) and min N1 (K2) reached, as well as the number of partial cycles (n) during the flight. The lump method takes into account only the partial cycles during the flight. A partial cycle corresponds to a significant deceleration followed by a significant acceleration without stopping the engine.




ARRIEL 1

Training Manual

Lump method

Recommended method CALCULATE N = K1 + nK2

CALCULATE N = 1 + n x 0.15 Highest N1 %

K1

100 99 98 97 96 95 94 93

1 0.9 0.8 0.7 0.65 0.6 0.55 0.5

N1%

Where : N = Number of cycles K = Number from chart for highest N1 n = Number of accelerations K2 = Number from chart for each accel.

Thus : N = 1 + 1 x 0.15 = 1.15

Lowest N1 %

Thus : N = 0.8 + 1 x 0.1 = 0.9 Gas Gen cycles

85 84 83 82 81

0.05

80 79 78 77 76

0.1

75 74 73 72 71 70 <70

Start

Stop

K2

0.15

0.15 TIME

EXAMPLE OF A FLIGHT PROFILE

CYCLE COUNTING For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

REMOVAL AND INSTALLATION OF THE POWER PLANT Removal - Installation

Installation of the engine on the support stand

The procedure for engine installation in the airframe is the responsibility of the aircraft manufacturer. The removal and installation procedures are therefore described in the aircraft maintenance manual. Nevertheless, this section deals with these procedures generally for training purposes.

The installation procedure requires the use of a special sling and support.

During installation, some points must be checked, such as :

The engine can be put in the vertical position by means of two struts mounted at the front of the support stand.

The engine is secured on its rear support by a clamp and on its front support by bolts.

- Before installation : • Check the engine general condition (casings, harnesses, pipes, accessories…) • Check the free rotation of the rotating assemblies • Check the condition and attachment of equipment • Remove the various blanks. - After installation : • Do a general check (attachments, levels, various connections…) • Do a ground run (starting, operation, stop, ventilation) • Do a flight test.




ARRIEL 1

Training Manual

REMOVAL - INSTALLATION - Aircraft manual - Checks : • Before installation • After installation

Pulley bloc

Lifting tool

INSTALLATION ON STAND

Trolley

- Horizontal position - Vertical position

Support stand

REMOVAL AND INSTALLATION OF THE POWER PLANT For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

REMOVAL AND INSTALLATION OF THE ACCESSORIES This part summarizes the accessories which can be replaced on the flight line (Line Replaceable Units).

Consumable or repairable components The accessories are considered as either consumable or repairable.

List of the accessories

Some accessories which are considered as consumable : fire detector, start injector, igniter plug, ignition unit, speed sensors, filters, strainers, magnetic plug…

Refer to the following pages. The table gives : - The accessory identification - The method of attachment - Remarks.

Removal and installation procedure Refer to maintenance manual. In a training course, procedures are dealt with in a video course and practical sessions.

Caution - Warning - Note Strictly follow the maintenance manual instructions : ignition unit, oil… Refer to ADVISORY NOTICES in this chapter.




ARRIEL 1

Training Manual

PROCEDURES

LIST OF ACCESSORIES - Identification - Method of attachment - Remarks

- Maintenance manual

PRECAUTIONS

CONSUMABLE OR REPAIRABLE COMPONENTS

- Note - Caution - Warning

- Consumable components - Repairable components - TBO / on-condition

REMOVAL AND INSTALLATION OF THE ACCESSORIES For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

REMOVAL AND INSTALLATION OF THE ACCESSORIES List of the engine accessories. ACCESSORY

ATTACHMENT

Front attachment

Bolted onto the accessory gearbox

Rear attachment

Two bolts on protecting tube rear mounting flange

Exhaust pipe

Ring of bolts on the power turbine casing

Pipes

Standard unions

Front lifting bracket

4 bolts on combustion chamber mounting flange

Rear lifting bracket

3 bolts on exhaust pipe mounting flange


REMARKS

1S, 1K, 1E



ARRIEL 1

Training Manual

REMOVAL AND INSTALLATION OF THE ACCESSORIES (CONTINUED) List of oil system accessories. ACCESSORIES

ATTACHMENT

Oil pumps

3 bolts on the accessory gearbox

Oil filter

Cover & bolt

Pre-blockage indicator

Screwed into the filter base

Oil pressure transmitter

Screwed into the filter base


3 bolts on the filter base

Electrical magnetic plug assy.

Screwed into the housing

Oil cooler

REMARKS

Installed in the aircraft

Magnetic plugs

Bayonet type attachment

Strainers

1 bolt

Rear bearing strainer in pump inlet

ACCESSORIES

ATTACHMENT

REMARKS


Clamp

List of air system accessories.




ARRIEL 1

Training Manual

REMOVAL AND INSTALLATION OF THE ACCESSORIES (CONTINUED) List of fuel system accessories. ACCESSORIES

ATTACHMENT

REMARKS

Fuel Control Unit

2 half-shells + clamp

Don't forget N2 drive coupling

Fuel filter

2 screws

Blockage indicator

Screwed into the FCU

1S, 1E, 1K

LP fuel filter

Threaded bowe

1S , 1E

Start purge valve

Installed on start electro-valve

Overspeed & drain valve

2 bolts on turbine casing

Pressurazing valve

Installed on overspeed and drain valve

Start injectors

2 screws on the combustion chamber casing

Combustion chamber drain valve

Screwed into the combustion chamber casing

Astatic Valve

Installed on ejector

1S, 1E

Ejector

Installed on protection tube

1S, 1E




ARRIEL 1

Training Manual

REMOVAL AND INSTALLATION OF THE ACCESSORIES (CONTINUED) List of indicating system accessories. ACCESSORIES

ATTACHMENT

REMARKS

N1 & N2 speed sensors

Two screws

1S only

Torque transmitter

Screwed into casing

Adjustable except 1S, 1E

N1 & N2 tacho-generators

2 bolts on Acc. gearbox

N2 optional

Tachometer box

Fitted in aircraft

Thermocouple harness

Thermocouples screwed into casing

Fragile probes

Overspeed sensor

Screwed into casing

Locating pin

ACCESSORIES

ATTACHMENT

REMARKS

Starter

Collar & clamp

Supply by a/c manufacturer

Ignition unit

Screws on a bracket

Igniter plug

2 screws on the combustion chamber casing

Ignition cables

Threaded union at each end

List of starting system accessories.


Post mod TU 271A



ARRIEL 1

Training Manual

REMOVAL AND INSTALLATION OF ENGINE MODULES Modular design The engine is of modular construction. This concept avoids the return of the complete engine to a specialized workshop and thus provides a higher operational availability and a reduction of maintenance costs.

Module replacement Each module is a unit which can be replaced without balancing or adaptation work.

- Inspection after replacement • Ground run check • Condition checks • Functional checks • Performance checks - Module follow-up • Engine log book and module log card

However, some precautions must be taken when replacing a module. This page mentions the main points related to this question :

- Interfaces • Intermodular parts • Equipment • Mounting.

- Reasons for module removal • Inspection (access to some components) • Replacement

Note : Refer to maintenance manual.

- Module identification • Identification plate on module • Compatibility table • Engine log book - Removal and installation conditions • Engine installed (or uninstalled) • Installation on working stand • Particular position (horizontal or vertical) - Tools • Standard tools • Special tools For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

M02 / M03 1 TIE BOLT NUT & 1 RING OF BOLTS

MODULE REPLACEMENT - Reasons - Identification - Conditions - Tools - Inspection after replacement - Module follow-up - Interfaces

MODULE M02

M03 / M04 1 RING OF BOLTS MODULE M03

MODULE M04

M02 / M01 4 BOLTS

MODULE M01

MODULE M05

M01 / M05 1 RING OF BOLTS

REMOVAL AND INSTALLATION OF ENGINE MODULES For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

DEEP MAINTENANCE In the future :

Deep maintenance, also called 3rd line or H Level, covers certain defined operations to repair an engine, module or accessory by replacing some parts without necessitating machining or test bed checking.

- Replacement of the axial compressor

It requires specific training, tooling and approved documentation.

- Any other operation that may be dearmed necessary.

- Replacement of the power turbine and/or the bearings

The following operations are possible : - Fuel injection manifold cleaning - Replacement of the gas generator turbine casing - Replacement of the gas generator rear bearing - Replacement of the nozzle guide vane - Operations on components of module 3 e.g. cleaning of the turbine shaft.




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Training Manual

AXIAL COMPRESSOR WHEEL

INJECTION MANIFOLD

GAS GENERATOR TURBINE CASING

REAR BEARING

GAS GENERATOR HOLLOW SHAFT

POWER TURBINE

NOZZLE GUIDE VANE

DEEP MAINTENANCE For training purposes only © Copyright - TURBOMECA - 2000



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REPAIR AND OVERHAUL Overhaul

Main procedure steps

Overhaul is a maintenance operation which is carried out when the engine (or module) has reached the end of its TBO, either operating hours or cycles.

- Engine reception

The overhauled engine (or module) is then put back into service with zero hours for a new TBO.

- Cleaning

Repair

- Inspection - Investigation

Repair is a maintenance operation which must be carried out when the engine (or module) is unserviceable. After a repair (IRAN), the engine (or module) is put back into service with its old TBO.

Note : TBO : Time Between Overhaul

- Disassembly

- Repair - Installation (of engine and accessories) - Tests - Delivery.

IRAN : Inspect & Repair As Necessary.




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REPAIR AND OVERHAUL SHOP ENGINE OR MODULE DELIVERY AFTER OVERHAUL WITH FULL TBO, OR REPAIRED

ENGINE OR MODULE AT THE END OF TBO OR FOR REPAIR

ENGINE ASSEMBLY

TESTS

DISASSEMBLY - REPAIR ACCESSORY ASSEMBLY DELIVERY DISASSEMBLY

INVESTIGATION REPAIR ENGINE RECEPTION CLEANING

INSPECTION

REPAIR AND OVERHAUL For training purposes only © Copyright - TURBOMECA - 2000



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15 - FAULT ANALYSIS AND TROUBLE SHOOTING - Fault analysis ................................................................ 15.2 - Trouble shooting ........................................................... 15.32 to 15.47



FAULT ANALYSIS AND TROUBLE SHOOTING

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FAULT ANALYSIS General

Fault analysis

Fault analysis is based on a school hypothesis which will bring about a better knowledge of the engine and will prepare the technician for all events.

The faults analysed in this chapter concern : - The bare engine

Fault analysis involves finding the effects of a given failure, even if it is unlikely to happen or results from particular circumstances.

- The oil system

During a training course, each case is commented on and discussed with the trainees.

- The fuel system

The analysis can be made at the end of each chapter or in the section devoted to maintenance.

- The air system

- Engine control - Engine indicating - Starting - The electrical system - The engine installation.




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FAILURE HYPOTHESIS (anomalies)

EFFECTS (symptoms)

Example : OIL FILTER

PARTIAL BLOCKAGE

PRE-BLOCKAGE INDICATOR AND PRESSURE DECREASE

COMPONENT HYPOTHESIS (or chosen case)

EFFECT (S)

FAULT ANALYSIS For training purposes only © Copyright - TURBOMECA - 2000



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Training Manual

FAULT ANALYSIS - BARE ENGINE (1) The air path

Foreign object ingestion

Dirt in the air path causes a reduced air flow and thus reduced power with a higher gas temperature and a reduced surge margin.

The damage of course depends upon the object ingested.

Compressor

Fuel injection system

Two main problems : - Erosion : it has the same effect as dirt with reduced strength of the components - Corrosion : it also causes reduced strength of the components.

Combustion chamber According to the combustion chamber anomaly (deformation, cracks…) : starting difficulties, overheat, instability of control system or, in the extreme, flame out.


The effects can be : power loss, vibration and in the extreme, engine shut-down.

A partial blockage can cause control instability, starting difficulties, and loss of power (max N1 unobtainable).

Turbines Erosion of the blades causes a loss of power, and corrosion of the blades causes reduced strength of the components. Blade creep can cause rubbing which causes abnormal noises and a short run-down time. In the event of blade breakage, the broken parts are retained by the containment shield.



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AIR PATH

COMPRESSOR - Erosion - Corrosion

- Dirt

COMBUSTION CHAMBER - Deformation - Cracks

TURBINES AIR INTAKE

FUEL INJECTION SYSTEM

- Foreign object ingestion

- Partial blockage

- Erosion, corrosion - Blade creep - Blade breakage

FAULT ANALYSIS - BARE ENGINE (1) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - BARE ENGINE (2) Exhaust system Any obstruction or damage to the exhaust system affects the engine operation : performance drop, tendency to surge...

Abnormal wear of the bearings and gears causes oil contamination which can be detected by magnetic plugs and by oil analysis. More serious damage will cause vibration and possibly an accessory drive failure.

Power transmission

Bearings Abnormal wear causes oil contamination, detected by the magnetic plugs and the oil analysis.

A failure of the power shaft causes overspeed and automatic shut-down (twin-engine version). Imbalance of the shaft will cause vibration.

A bearing failure causes vibration, instability of control and performance drop. A failure or major damage can also cause engine hang up during start or blockage of the rotating assembly.

Accessory drive

Sealing An internal seal leakage causes either a fluid or gas leak ; consequences according to the system concerned. Any external leak is generally visible.

A failure of the accessory drive shaft will cause an engine shut-down (oil and fuel pump stop...). A failure of one accessory drive shaft will cause an effect according to the accessory concerned.




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EXHAUST SYSTEM - Deformation - Obstruction

BEARINGS - Wear - Failure

ACCESSORY DRIVE - Accessory drive shaft failure - Accessory shaft failure - Wear of gears and bearings

SEALING

POWER TRANSMISSION

- Internal leak : Gas, air, oil, fuel - External leak

- Failure - Imbalance

FAULT ANALYSIS - BARE ENGINE (2) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - OIL SYSTEM (1) Oil tank

If the pump pressure relief valve is jammed :

When the oil level is too high, the expansion volume becomes insufficient, and could cause a leak through the air vent.

- Open : loss of pressure

When the oil level is too low, there is a risk of insufficient lubrication (the loss of pressure is obviously indicated).

Cooling unit

Oil filter

If the cooling coil is obstructed, the flow is ensured through the by-pass valve and causes an increase of oil temperature.

- Closed : dormant fault.

A partial blockage is indicated by the pre-blockage indicator. When a complete blockage occurs, the lubrication is ensured through the by-pass valve, with a risk of system contamination.

Note : In case of a pressure drop being confirmed by the indicating system, the engine should be shut-down to prevent more serious damage. An increase of pressure also indicates a fault in the system (obstruction of jets for example).

Oil pumps A drive shaft failure causes a rapid pressure drop and lubrication failure, with cockpit indication. The seizing of a pump causes shaft overtorque with the risk of failure.




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OIL TANK

OIL FILTER

- Oil level too high - Oil level too low

- Partial blockage - Complete blockage

OIL PUMPS COULING UNIT

- Drive shaft failure - Pump seizing - Pressure relief valve : open, closed

- Cooling coil obstructed

FAULT ANALYSIS - OIL SYSTEM (1) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - OIL SYSTEM (2) Internal supply

Oil contamination

A local lubrication problem results in a rather quick process of deterioration.

It is already the consequence of an anomaly. Example : fuel dilution of the oil, oil contamination, particles on magnetic plugs or in the filter, oil sampling analysis results (out of tolerance).

It can be detected by abnormal pressure and/or temperature, by particles on magnetic plugs or by the oil sampling analysis.

Breathing The obstruction of a breathing line (or anomaly of the centrifugal breather) may cause overpressure, lubrication problem, or a leak through the sealing system… The obstruction of the general air vent causes foaming in the tank.

Sealing anomaly An "external" leak is indicated by a visible leak and increased oil consumption. An "internal" leak causes an oil leak into the air system, increased consumption, pressure fluctuations, smoke…




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INTERNAL SUPPLY

BREATHING

- Local anomaly (obstruction of jet)

- Breathing line obstruction - Centrifugal breather - Air vent line obstruction

OIL CONTAMINATION - Dilution - Contamination - Particles on magnetic plugs - Oil sampling analysis results

SEALING ANOMALY - "External" sealing - "Internal" sealing

FAULT ANALYSIS - OIL SYSTEM (2) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - AIR SYSTEM Internal pressurisation system

FCU air supply

Any anomaly (obstruction, abnormal clearance) will result in operating problems :

A leak, breakage or clogging of the restrictor will give an incorrect signal to the FCU affecting the engine acceleration and deceleration (according to version). A complete loss of the pressure will cause very low N1.

- Internal oil leak (as labyrinth pressurisation is affected) - Local overheat (as the system is used to cool the internal parts)

Start injector supply

- Loss of power if too much air is tapped.

If P2 air tapping is obstructed : Starting problems.

Power turbine bearing pressurisation

Injector ventilation ball valve

Breakage or obstruction of the P2 air pipe. The labyrinths are therefore not pressurised : - Oil leak from hot section

If the valve sticks closed there will be no injector ventilation, causing injector clogging.

- Consumption - Smoke emission.


Air tappings for the aircraft If the air supply is obstructed : refer to aircraft system concerned. If too much air is tapped, it affects the engine performance (W, t4, CH…).


If the valve sticks open this can cause a leak of fuel into the air system and cause starting difficulty.

If the valve remains open, it causes a permanent air discharge and a decrease of available power. If the valve remains closed, it can lead to engine surge at low N1 speeds.



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INTERNAL PRESSURISATION SYSTEM

POWER TURBINE BEARING PRESSURISATION

COMPRESSOR BLEED VALVE

START INJECTOR SUPPLY - P2 air tapping blockage

- Obstruction - Abnormal clearance - Leak

- Broken pipe - Obstruction

- Valve remains "open" - Valve remains "closed"

A

AIRCRAFT AIR TAPPINGS - Air supply anomaly - Excessive tapping

B

FCU AIR SUPPLY

INJECTOR VENTILATION BALL VALVE

- Leak - Broken pipe - Obstruction

- Valve jammed "open" - Valve jammed "closed"

FAULT ANALYSIS - AIR SYSTEM For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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FAULT ANALYSIS - FUEL SYSTEM (1) Aircraft fuel system

Fuel filter

An aircraft fuel system anomaly will cause an incorrect supply to the engine fuel system.

In case of partial blockage : indication by the pre-blockage indicator.

The effects depend upon the anomaly. For example :

In case of blockage : by-pass flow with possible fluctuations of engine ratings.

- Reduced performance - By-pass valve jammed closed : dormant fault - Starting difficulties. - By-pass valve jammed open : by-pass flow with system contamination.

Fuel pump Total failure (i.e. : drive shaft breakage) : engine shutdown and/or no start. - Pressure relief valve jammed closed : dormant fault, overpressure hazard - Pressure relief valve jammed open : reduced performance or even engine shut-down - Drive shaft seal leak : fuel leak from the drain.




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AIRCRAFT FUEL SYSTEM

FUEL PUMP - Total failure (shaft breakage) - Pressure relief valve (jammed open or closed) - Shaft seal leak

- Fuel supply to the engine fuel system

FUEL FILTER - Partial blockage - Blockage - By-pass valve (jammed open or closed)

FAULT ANALYSIS - FUEL SYSTEM (1) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - FUEL SYSTEM (2) Start electro-valve

Overspeed and drain valve

Electro-valve : the valve remains closed, no supply to the injectors, no start.

Pressurising valve jammed "closed" : no supply to the injection wheel and therefore no start ; there is however a fuel supply to the injectors which causes a slight gas temperature increasing.

Pressure switch : if the pressure switch does not operate, the re-injection prohibit function is lost. If the switch contact is failed, no supply to the electro-valve and therefore no start.

Pressurising valve jammed "open" : premature fuel supply to injection wheel causing difficult ignition.

Clogging : starting difficulties or no starting.

Dual valve : no start if the valve remains in "drain" position, clogging of the injection wheel distributor, if it remains in "injection" position.

Incorrect penetration of injectors : starting difficulties (clogging or deterioration of injectors).

Overspeed electro-valve inoperative : no shut-down in case of power turbine overspeed.

Loss of ventilation : clogging after a certain operating time.

Fuel injection wheel

Start injectors

Insufficient sealing : internal fuel leak, possible contamination of P2 air and coking of internal parts. Note : Starting with only one injector operative is possible.

Clogging of the fuel distributor : fuel flow limited and therefore max N1 speed unobtainable.

Note : Refer to maintenance manual for check procedure and corrective action.




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START INJECTORS

- Solenoid - Pressure switch

- Blocked - Incorrect penetration - No ventilation

OVERSPEED AND DRAIN VALVE INJECTION WHEEL

- Pressurising valve : • jammed "open" • jammed "closed" - Dual valve anomaly - Overspeed electro-valve inoperative

- Leak - Clogging

FAULT ANALYSIS - FUEL SYSTEM (2) For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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FAULT ANALYSIS - CONTROL SYSTEM (1) Engine control lever Breakage (or disconnection) of the linkage : the FCU lever remains in its initial position. Manual control is not possible for starting, stopping or emergency. Seizing of the mechanism (or of the valves) : more force required to move the control lever. Incorrect adjustment of the lever : the control lever position does not correspond to the FCU lever position. Effect depending upon maladjustment (eg : starting or shut-down difficulties).

Anticipator control Breakage of the collective pitch FCU mechanism : the governing system operates on one static droop line. Therefore no droop compensation. In twin-engine configuration, this will result in an N1 desynchronisation of the engines. Incorrect adjustment of the control : the datum does not correspond to the collective pitch position. The rotor speed is affected. In twin-engine configuration, split of the two N1 if the two data are different.




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ENGINE CONTROL LEVER

ANTICIPATOR CONTROL

- Linkage broken or disconnected - Seizing - Incorrect adjustment

- Linkage broken - Incorrect adjustment

ENGINE CONTROL LEVER

ANTICIPATOR CONTROL

FAULT ANALYSIS - CONTROL SYSTEM (1) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - CONTROL SYSTEM (2) Power turbine governor

Acceleration control unit

Failure of the drive shaft : max N1 datum, the engine accelerates to max N1 stop. In twin-engine configurations, the other engine decelerates to compensate.

P2 air supply pipe failure : the engine decelerates to minimum fuel flow. In twin-engine configuration, the other engine accelerates to compensate.

Problem in the hydraulic system : wrong modulated pressure, the required N1 is not obtained, possible fluctuations.

P2 air supply anomaly : any supply anomaly will affect the acceleration time and therefore the response time. A P2 supply problem to the deceleration control unit (for the engines provided with this device) could cause flameout in extreme transient conditions.

Anticipator : see previous page.

Gas generator governor

Fuel metering device

Failure of the drive shaft : the engine acceleration to maximun fuel flow and an overspeed is probable (extremely remote as the shear section of the drive is on the fuel pump shaft). Compensating capsule anomaly : N1 will tend to vary with fuel temperature. The "sagging" of the capsule will reduce max N1. Hydraulic system anomaly : instability, response time out of tolerances.


Any anomaly (eg : jamming of metering valve or constant ∆P valve) results in an incorrect fuel flow control and therefore instability. Note : Remember that fuel flow can be controlled manually with the engine control lever.

Working piston Any operation anomaly (a blockage) of the working piston causes starting difficulties : start impossible or slow, rapide start with overheat.



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GAS GENERATOR GOVERNOR

- Drive shaft failure - Hydraulic system anomaly

- Drive shaft failure - Compensating capsule anomaly - Hydraulic system anomaly

WORKING PISTON - Operating anomaly

METERING DEVICE


- Any anomaly

- P2 air supply pipe failure - P2 air supply anomaly




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FAULT ANALYSIS - ENGINE INDICATING Rotation speed indication

Oil pressure indication

- Most problems lead to a complete loss of signal and therefore no indication

Min oil pressure switch : two possibilities : - No indicating light

- Check other parameters to confirm the failure of the indicating system (Refer to flight manual for operating instruction to be applied).

- Indicating light permanently "on".

Gas temperature indication

Note : Check oil pressure and torque indication to confirm the pressure switch anomaly.

Thermocouple anomaly : possible alteration of the indication ; the mean value of the remaining probes is read.

Oil pressure transmitter : no indication at all or incorrect indication an case of failure.

Broken wire of the pyrometric harness : loss of the indication.

Note : Check torque and min pressure light to confirm the failure.

Loose thermocouple probe : fluctuations or wrong indication.

Torque indication Hydraulic torquemeter : jamming or leak will cause an incorrect indication. Note : The system does not operate in case of lubricating pressure failure. Torquemeter transmitter : no indication or incorrect indication in case of malfunction or incorrect adjustment. Note : Pressure check to determine the failed component of the system.




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ROTATION SPEED INDICATION

GAS TEMPERATURE INDICATION

- Anomaly of the speed sensor indication

- Thermocouple anomaly - Broken wire of the pyrometric harness - Loose thermocouple probe

TORQUE INDICATION

OIL PRESSURE INDICATION

- Hydraulic torquemeter anomaly - Torquemeter transmitter anomaly

- Min oil pressure switch anomaly - Oil pressure transmitter anomaly




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FAULT ANALYSIS - STARTING Electrical power supply

Starting control system

A low DC supply voltage will cause difficult engine starting and excessive gas temperature.

With a total power supply failure there is no voltage on the accessories so no cranking and no ignition.

Note : The voltage should not decrease below 15 Volts during starting.

With no starter power supply there is no cranking ; but the ignition operates (operation of the ignition system can be heard).

Starter

With no ignition power supply there is no ignition ; but the starter operates.

If the starter is failed : - Insufficient torque during starting, slow acceleration with high gas temperature - No starting.

Ignition unit A High Energy ignition unit failure causes no ignition at all or insufficient energy to obtain the correct pulse rate. Note : Starting is nevertheless possible with one unit inoperative.

Igniter plug In case of an igniter plug problem, no sparks are produced, or the sparks do not have enough energy to ignite the fuel. Note : Starting is possible with one plug inoperative.




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ELECTRICAL POWER SUPPLY

STARTER

STARTING CONTROL SYSTEM

- Low DC supply voltage

- Starter motor anomaly

- Total power supply loss - Starter power supply loss - Ignition power supply loss

IGNITION UNIT

IGNITER PLUG

- HE ignition unit anomaly

- Igniter anomaly

FAULT ANALYSIS - STARTING For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

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FAULT ANALYSIS - ELECTRICAL SYSTEM (1) Electrical power supply - DC power supply anomaly during start : no starting or starting "difficulties" (sluggish start, high gas temperature) - DC power supply anomaly in "normal operation" : • Total failure : the engine remains in operation but without some indicating and without overspeed safety. • Battery failure : back-up by DC generator • Generator failure : back-up by battery or other source. - Internal supply anomaly of the tachometer box : an internal supply anomaly will cause the non operation of the system (the light remains illuminated).

Start control system Refer to fault analysis of starting.

Indicating systems Refer to fault analysis of indicating systems.




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ELECTRICAL POWER SUPPLY - Anomaly of DC supply : • during start • in normal operation - Internal supply anomaly of the tachometer box

START CONTROL SYSTEM - Refer to fault analysis of starting

INDICATING SYSTEMS - Refer to indicating systems

FAULT ANALYSIS - ELECTRICAL SYSTEM (1) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - ELECTRICAL SYSTEM (2) Overspeed pick-up

Super Contingency Power system

One pick-up : fault indicated by the light (remaining "on" above 25 % N2).

Abnormal operation of the control system : no arming of super contingency rating.

Overspeed electro-valve

Abnormal operation of SCP box : no indicating of "SCP" or recording of life not correct.

Electro-valve failure : no engine shut-down in case of overspeed; dormant fault which would be detected during the periodic test. Valve jammed open : no start (remote probability).

Tachometer box Inoperative : no overspeed system capability but the problem is indicated by the test. Unwarranted operation : extremely remote probability considering the design of the system.




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OVERSPEED PICK-UP

OVERSPEED ELECTRO-VALVE

- One pick-up

- Electro-valve failure - Valve jammed "open" TEST OSCILLATOR

S

120 %

N2

120 %

N2

V


25 %

TACHOMETER BOX

SCP SYSTEM

- Inoperative - Unwarranted operation

- Arming circuit inoperative - SCP box

FAULT ANALYSIS - ELECTRICAL SYSTEM (2) For training purposes only © Copyright - TURBOMECA - 2000



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FAULT ANALYSIS - ENGINE INSTALLATION Engine compartment

Drains and air vents

Lack of ventilation can cause an increase of temperature which can be, in extreme cases, detected by the fire detection system.

In case of obstruction of a drain, effect according to the drain system (refer to system concerned).

Engine attachment

Particular attention to obstruction hazard caused by deformation during engine removal and installation or caused by insects in some countries.

Incorrect adjustment, abnormal clearance or misalignment will cause vibration or abnormal stresses with all the usual consequences.

Power transmission

Air intake and gas exhaust

A failure of the power shaft causes a power turbine overspeed and automatic engine shut-down by the overspeed protection system (twin-engine only).

A partial obstruction affects the engine performance. Particular instructions are given in the maintenance manual, for engine operation in a "hostile atmosphere" : - Sand : increases erosion - Salt : causes corrosion - Pollution : both erosion and corrosion.

Misalignment of the shaft causes vibration and possible failure.

Fire protection The engine fire protection system is described in the aircraft manual.

Air tappings Any air tapping affects the engine performance. An excessive air tapping reduces the power available ; or increases the gas temperature for a given power rating.




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ENGINE COMPARTMENT

ENGINE ATTACHMENT

- Lack of ventilation

- Incorrect adjustment - Abnormal clearance - Misalignment

AIR INTAKE AND GAS EXHAUST - Partial obstruction - Dirty atmosphere POWER TRANSMISSION - Shaft failure - Misalignment

FIRE PROTECTION

AIR TAPPING

DRAINS AND AIR VENTS

- Refer to aircraft documentation - Detector anomaly

- Excessive air tapping

- Obstruction

FAULT ANALYSIS - ENGINE INSTALLATION For training purposes only © Copyright - TURBOMECA - 2000



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TROUBLE SHOOTING General

Repair procedure

Trouble shooting is a very important aspect of maintenance.

The corrective maintenance actions should be guided by two main considerations :

An "efficient" diagnosis reduces the extra maintenance costs due to unjustified removals and additional diagnosis time.

- Minimum downtime - Justified removal of components.

In fact, even with a very high reliability product, failure is inevitable and required actions should be taken efficiently. After the fault analysis which consists of finding the effect of a given failure, this section considers the case in reverse ; i.e. : finding the probable cause of a fault.

The procedure to be applied depends on the case but in general, a good knowledge of the product and a methodical research would permit a safe diagnosis and a quick corrective action. Generally, the procedure includes failure identification, its analysis, the isolation of the component, and the repair choice.




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Inevitable

Random

Fault (single, double, dormant)

Trouble shooting - Diagnosis - Remedy - Repair - Check

MTTR (Mean Time To Repair)

- Adequate means and procedures - Training of personnel

Or other perception

Symptoms (and other additional indications…) All factors should be taken into consideration as well as the interactions. Analysis of the fault Identification of the faulty component

Additional checks

Total time required for repairing

Deduction

Substitution

Remedy (adjustment, replacement, cleaning, repair...)

TROUBLE SHOOTING For training purposes only © Copyright - TURBOMECA - 2000



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No effect after selecting start N doesn't increase

Is ventilation possible ? Yes

No

- Overspeed not rearmed - Starting circuit (circuit breaker, selector switch, relay …)

- Starter contactor - Electrical supply - Starter

Note : Further tests (engaging noise of the contactor...) help locate the failure.

TROUBLE SHOOTING - STARTING FAULTS (1) For training purposes only © Copyright - TURBOMECA - 2000


15.34


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On selection of start, N increases, but no t4

Yes

The ignition system operates (noise of HE components)

- Start electro-valve - Injectors Start is possible with one injector and one igniter plug provided they are on the same side

No

- HE ignition units - Igniter plugs Note : Refer to the test procedure for discrimination

Or fuel supply problem

Note : It is also possible to check for a fuel flow through the combustion chamber drain.

Yes

Fuel flows

Ignition system

No

- Start electro-valve - Fuel supply




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Abnormal t4

t4 ≈ 200°

Increase due to the injectors, but the main fuel system is not supplied

- Pressurising valve - Overspeed and drain valve

t4 > 200° but insufficient

t4 too high

- Overspeed drain valve - FCU - Control lever - Inadequate fuel supply (LP system, filters...)

- FCU - Control lever - Procedures

Note : In all cases, check the electrical supply (battery voltage)

Variant : N and t4 increase, but the starting is not effective, so no N2

Failure of the accessory drive shaft



15.36


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Shut-down selected by moving the throttle lever rearwards

N1 deceleration Yes

No

Stop selection

Control lever disconnected

The engine stops N1 , t4 No Yes

Yes

Correct rundown time

Normal shut-down

Poor sealing of the fuel system No

The engine shut-down can then be affected by the manual control system or by the fuel shut-off (fire) valve. Further checks required.

Abnormal friction of the rotating assembly

TROUBLE SHOOTING - FAULTS DURING SHUT-DOWN For training purposes only © Copyright - TURBOMECA - 2000



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Ventilation selection (press and hold)

Note : 15 sec. max to avoid starter overheat

N1 indication

Yes

No

The gas generator is driven

The starter turns

Yes

No

Yes

"Normal" ventilation

Accessory drive train

N1 indication

No

Starting is possible Yes

No

Ventilation selector

- Starter contactor - Starter - Electrical supply

TROUBLE SHOOTING - FAULT DURING VENTILATION For training purposes only © Copyright - TURBOMECA - 2000


15.38


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Abnormal oil pressure indication

Low

No pressure

- Oil condition - Sealing - Internal blockage - Pressure relief valve

Fluctuation

High

- Filter blockage - Pressure relief valve

- Measuring system - Blockage of a jet

Min oil pressure light illuminated Yes

- Failure of the pump shaft - Pressure relief valve - Internal blockage - Large internal or external leak

No

Pressure indicating system : - Transmitter - Indicator - Harness

TROUBLE SHOOTING - LUBRICATION FAULTS (1) For training purposes only © Copyright - TURBOMECA - 2000



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Abnormal oil temperature indication

High

Low

Measuring system

- Measuring system - Insufficient cooling - Local lubrication problem (blockage of a jet)

Abnormal oil consumption

Yes

Pipe or accessory

No

Visible leak

External leak

Oil contamination

Detection

Internal leak

Contamination of the bleed air Leak from the cold section labyrinth seals (front section)

Smoke and oil in the exhaust pipe Leak from the hot section labyrinth seals. (rear section)

General vent pipe failure (blockage, wrong indication)

P2 air pipe failure

- Magnetic plugs - Analysis - Color, aspect

Corrective action

According to amount, origin and rate of contamination...

TROUBLE SHOOTING - LUBRICATION FAULTS (2) For training purposes only © Copyright - TURBOMECA - 2000


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Uncommanded engine shut-down

N2, N1, Tq, t4, oil pressure

Operation of the power turbine overspeed system Yes

No

Water or ice ingestion

Actual overspeed Yes

Doubt

- Failure of the power transmission shaft - FCU

No

Engine internal anomaly

Abnormal fuel supply : - Pump shaft failure - Pipe failure - Water in fuel - FCU

- Loss of signal - Tachometer box Note : Unlikely

Rearming and corrective actions

Note : In a twin-engine configuration, the engine which remains in operation supplies the required power within its limits.

TROUBLE SHOOTING - FAULTS LEADING TO ENGINE SHUT-DOWN IN FLIGHT For training purposes only © Copyright - TURBOMECA - 2000



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Abnormal gas temperature indication

Dirty compressor

Measuring system

Engine internal problem

Compressor surge

Bleed valve (closed)

FCU acceleration controller

Engine anomaly (air intake, compressor...)

Loss of power

Max N1 reached Yes

No

- Torque and gas temperature indication - Engine : dirty compressor, turbine creep,etc ...

- Blockage of the injection system - Isufficient fuel supply (pumps, filters...) - FCU - temperature compensation device - Anticipator, adjusment

Note : Particular attention : check of the max N1.

TROUBLE SHOOTING - MISCELLANEOUS CASES (1) For training purposes only © Copyright - TURBOMECA - 2000



ARRIEL 1

Training Manual

Gas generator rotation speed N1

Incorrect response time

Overspeed

FCU

Uncommanded acceleration

FCU

- FCU - Anticipator - Gas generator internal problem Uncommanded deceleration

- Abnormal fuel supply - FCU - Abnormal operation of one of the fuel system accessories (refer to the chapter "fuel system") - Loss of P2 supply to FCU

Fluctuation

- Air in the fuel system - Dirt in the fuel system - Constant ∆P valve - Blockage of the centrifugal wheel - FCU




ARRIEL 1

Training Manual

Power turbine rotation speed N2

Incorrect speed

Overspeed

- Indicator - FCU - Anticipator adjustment

- Failure of the transmission shaft - Control system failure

Vibration

Power transmission shaft

Engine - aircraft alignment

Engine attachment

Gas generator or power turbine rotating assembly



15.44


ARRIEL 1

Training Manual Note : Failures which cause abnormal indication. - Inaccurate indication (transmitter / receiver) - Systems associated with the engine

Instruments

Refer to other cases Lights Fire "failure"

Fire warning

Chip detection

Low oil pressure

Oil filter pre-blockage Fuel filter pre-blockage (according to version)

Unjustified illumination

Refer to aircraft documentation

No illumination in test mode

Refer to aircraft documentation

Justified illumination

Overheat or fire


Detector failure

No illumination in test mode

Test system

No illumination in the event of overheat

Detection circuit


Deposit of particles


Sensor "sensibility"

No illumination despite particles

Electrical magnetic plug or wiring failure


Pressure drop


Pressure switch

No illumination despite effective pressure drop

Pressure switch

Justified indication

Blockage

Unjustified indication

Indicator

No indication despite the differencial pressure increase

Indicator




Training Manual

ARRIEL 1

TROUBLE SHOOTING - CONCLUSION Despite the high reliability of the product failures remain inevitable and happen at random. But their rate and effects can be reduced if the "enemies" of the engine are taken into consideration. When the failure occurs, you have to be in a position to correct it.

"Enemies" of the engine The traditional adverse conditions for this type of engine are : - Supply (air, oil, fuel, electricity) - Operation ("non respect" of instructions and procedures) - Maintenance ("non respect" of inspection frequencies and of the strict application of the procedures).




ARRIEL 1

Training Manual

OPERATION

FUEL - Not in conformity with specifications - Water in fuel - Sulphur + salt in the air = sulfidation.

- "Non respect" of instructions and procedures - Severe operating conditions.

OIL

AIR

- Not in conformity with specifications - Miscellaneous contamination.

- Sand - Salt - Miscellaneous pollution.

MAINTENANCE ELECTRICITY

- "Non respect" of inspection frequencies - Various mistakes - Wrong logistics.

- Too low voltage during starting - Interference.

TROUBLE SHOOTING - CONCLUSION For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

16 - CHECKING OF KNOWLEDGE - Introduction .................................................................. 16.2 - Questionnaire 1 ............................................................. 16.3 - Questionnaire 2 ............................................................. 16.6 - Questionnaire 3 ............................................................. 16.12 - Questionnaire 4 .............................................................. 16.15 to 16.30



CHECKING OF KNOWLEDGE

ARRIEL 1

Training Manual

INTRODUCTION Method

Types of questionnaires

Continuous checking helps to ensure the information is assimilated. It is more a method of work than a testing in the traditional sense.

Several types of questionnaire can be employed during a course : - Traditional written questionnaire

Objectives of the questionnaires

- "Short answer" questionnaire

The questionnaires permit a progressive assimilation and long term retention. The questionnaires are a subject for discussion (effects of group dynamics). They also permit students to consider important subjects several times under different aspects.

- Multi Choice Questionnaire (MCQ) - Oral questionnaire - Learning Through Teaching (LTT ; the student has to explain a given subject).

Integration into the training programme - First hour every day for revision of the subjects previously studied - After each chapter (or module) of the course - At the end of the training course.


Examination The final examination at the end of the course consists of three tests : written, oral and practical. A certificate and an approval card are given to the student if the results are satisfactory.



ARRIEL 1

Training Manual

QUESTIONNAIRE 1 This traditional questionnaire is established according to the same plan as the training manual in which the answers can be found.

Engine 1 - List the main components of the gas generator. 2 - State the following characteristics :

Power plant

• Compression ratio

1 - List the main functional components of the power plant.

• Turbine entry temperature • N2 speed at 100 %

2 - Explain the thermodynamic operation of the engine. 3 - State the following features (at take-off, in standard atmosphere) :

• N1 speed at 100 % 3 - Describe the power turbine assembly.

• Power on the shaft

4 - Describe the fuel injection system.

• Output shaft rotation speed

5 - List the engine driven accessories.

• Mass of the engine with specific equipment

6 - List the bearings which support the gas generator.

• Main overall dimensions of the power plant

7 - Describe the system used for bearing sealing.

4 - Explain the principle of engine adaptation to helicopter power requirements. 5 - Give a definition of the operating ratings. 6 - How do temperature and altitude affect the engine performance.


8 - Describe the modular construction of the engine. 9 - Describe the engine air intake. 10 - List the manufacturing materials of the engine main components.



ARRIEL 1

Training Manual

QUESTIONNAIRE 1 (continued) Oil system

Control system

1 - Draw a simplified diagram of the oil system.

1 - List the main functions of the control system.

2 - Explain the general operation of the oil system.

2 - Explain the basic principle of the control system.

3 - Describe the oil filter assembly.

3 - Explain the operating principle of the speed control.

4 - State the location of strainers and magnetic plugs.

4 - Describe the purpose and operation of the anticipator control.

Air system

5 - Explain the operation of the acceleration controller.

1 - List the functions ensured by the internal air system (secondary system).

6 - What are the main sections of the FCU.

2 - List the function of the various air tappings. 3 - Why are the start injectors ventilated ? 4 - Explain the purpose and the operation of the compressor bleed valve.

7 - Describe and explain the operation of the power turbine overspeed system. 8 - Describe the principle of load sharing in a twin engine configuration.

Indicating system and manual control

Fuel system

1 - Describe the manual control system.

1 - What is the purpose of the Booster pump.

2 - Describe the power turbine speed indicating system.

2 - Describe the fuel pump.

3 - Explain the operating principle of the torquemeter system.

3 - Describe the fuel metering unit.

4 - Describe the gas temperature indicating system.

4 - What is the purpose of the constant ∆P valve. 5 - Explain the principle of fuel injection (main and starting injection). 6 - Explain the operation of the overspeed & drain valve.




ARRIEL 1

Training Manual

QUESTIONNAIRE 1 (continued) Starting

Limitations and engine handling

1 - Describe the cranking function of the engine.

1 - List the main operating limitations of N1.

2 - Describe the ignition system (ignition unit and igniter plugs).

2 - Describe the engine starting procedure.

3 - List the main phases of the starting cycle.

Various aspects of maintenance

4 - Describe the starting control electrical system.

1 - List the main practices of a periodic inspection. 2 - List the methods used for "on condition monitoring".

Electrical system

3 - List the technical publications used for engine maintenance.

1 - List the engine electrical accessories. 2 - List the sensors (state the type of signal produced). 3 - Describe the electrical harnesses and connectors.

Maintenance procedures 1 - Describe the compressor cleaning procedure.

Engine installation

2 - Name the LRUs of the air system.

1 - Describe the attachment of the engine to the aircraft.

3 - Explain the attachment of each of the modules.

2 - Describe the engine power drive and the power transmission.

Fault analysis and trouble shooting

3 - List the various engine / aircraft interfaces.

1 - Carry out the fault analysis exercises.

4 - Describe the fire protection system of the engine.

2 - Carry out the trouble shooting exercises.




ARRIEL 1

Training Manual

QUESTIONNAIRE 2

Questions

The following questions require short and accurate answers. The student can answer orally or in the space provided for the answers. Questions

Answers

Answers

10 - Flight envelope - Max altitude ? 11 - Flight envelope Max temperature ? 12 - Start envelope - Max altitude ?

1 - ARRIEL 1 power class ?

13 - Engine air flow at 100 % N1 ?

2 - Power turbine rotation speed at 100 % ?

14 - Overall compression ratio ? 15 - Max turbine entry temperature ?

3 - Type of main fuel injection ? 4 - Number of engine modules ? 5 - Number of power turbine stages ?

16 - Gas generator rotation speed at 100 % N1 ? 17 - Direction of rotation of the gas generator ?

6 - Meaning of AEO ? 7 - Mass of the equipped engine ?

18 - Direction of rotation of the power turbine ?

8 - Power evolution when altitude increases ?

19 - Manufacturing material for the axial compressor ?

9 - Specific fuel consumption at 350 kW ?

20 - What type of bearing is the axial compressor bearing ?




ARRIEL 1

Training Manual

QUESTIONNAIRE 2 (continued) Questions 21 - How is the axial compressor mounted on the gas generator module ? 22 - Axial compressor compression ratio ? 23 - Manufacturing material for the centrifugal compressor wheel ? 24 - Number of stages of the centrifugal compressor diffuser ? 25 - Type of combustion chamber ? 26 - Manufacturing material for the combustion chamber ?

Answers

Questions

Answers

30 - Type of power turbine front bearing ? 31 - Type of gas generator rear bearing ? 32 - To which module does the power turbine nozzle guide vane belong ? 33 - Type of power turbine ? 34 - Does the exhaust pipe belong to one module (yes or no) ? 35 - Type of exhaust pipe attachment ? 36 - Number of gears in the reduction gearbox ?

27 - Type of main fuel injection ?

37 - Rotation speed of the intermediate gear of the reduction gearbox ?

28 - Pressure drop in the combustion chamber ?

38 - Number of driven accessories on the accessory gearbox ?

29 - Number of stages of the gas generator turbine ?

39 - Manufacturing material for the accessory gearbox casing ?




ARRIEL 1

Training Manual

QUESTIONNAIRE 2 (continued) Questions 40 - Is the oil pressure adjustable ?

Answers

Questions

Answers

50 - Setting of the low oil pressure switch ?

41 - Number of pumps in the oil pump pack ?

51 - Max oil temperature ?

42 - Type of oil pumps ?

52 - Location of the centrifugal breather ?

43 - What is the setting of the check valve at the pressure pump outlet ?

53 - Air tapping for the pressurisation of the power turbine front bearing ?

44 - Filtering ability of the oil filter?

54 - Air pressure at the centrifugal compressor outlet ?

45 - Setting of the oil filter by-pass valve?

55 - Temperature at the centrifugal compressor outlet ?

46 - Which bearings are ball bearings ? 47 - Type of seal for the gas generator rear bearing sealing ? 48 - Max oil consumption ? 49 - Type of oil pressure transmitter ?


56 - When does the start injector ventilation begin ? 57 - Max air tapping flow ? 58 - Type of compressor bleed valve ? 59 - Position of the bleed valve during starting ?



ARRIEL 1

Training Manual

QUESTIONNAIRE 2 (continued) Questions

Answers

Questions

Answers

60 - What are the bleed valve control signals ?

71 - How is the anticipator signal transmitted ?

61 - Where is the bleed valve fitted ?

72 - Setting of the fuel pressurising valve?

62 - Type of fuel filter ? 63 - Filtering ability of the fuel filter ? 64 - Setting of the fuel filter by-pass valve ? 65 - Type of fuel pump ?

73 - Fuel flow through the start injectors? 74 - Number of start injectors ? 75 - Position of the combustion chamber drain valve when the engine is stopped ?

66 - Position of the pump pressure relief valve in normal engine running ?

76 - Type of fuel control system ?

67 - Type of fuel metering device ?

77 - Signals for the acceleration controller

68 - Position of the constant ∆P valve when the engine is stopped ?

78 - Average response time of the control system

69 - Type of manual fuel flow control ?

79 - Is the static droop compensated

70 - Type of valve for injector ventilation ?

80 - Position of the main valve with lever in emergency plus




ARRIEL 1

Training Manual

QUESTIONNAIRE 2 (continued) Questions 81 - Meaning of OEI ?

Answers

Questions

Answers

91 - Where is the oil pressure transmitter located ?

82 - Type of N2 controller ? 83 - Position of the auxiliary valve with the lever in the emergency minus range ?

92 - How are the thermocouples connected (parallel or series) ? 93 - Location of the torquemeter ?

84 - Closing threshold of the reinjection prohibition switch 85 - What keeps the metering needle closed when the control lever is closed ? 86 - Position of the manual control lever in normal engine running ?

94 - Type of torque sensor ? 95 - Type of signal output by the torque sensor ? 96 - Is the torque transmitter associated with a particular module ?

87 - Type of speed sensors ? 88 - What is the average torque pressure at 100 % torque ?

97 - Type of starter ? 98 - Type of ignition system ?

89 - How does the low oil pressure switch sense the pressure ? 90 - Number of thermocouple probes ?


99 - Gas generator rotation speed at starter cut-off ?



ARRIEL 1

Training Manual

QUESTIONNAIRE 2 (continued) Questions 100 - Number of igniter plugs ?

Answers

Questions

Answers

111 - Max gas temperature during starting ?

101 - Max duration of a ventilation ? 112 - Low oil pressure switch setting ? 102 - Is the ignition cable integral with the igniter plug ? 103 - Number of electrical connectors ?

113 - Max oil temperature ? 114 - Min electrical supply voltage before starting ?

104 - Location of the tachometer box ? 115 - Type of recommended lubricant ? 105 - Type of seal on the power shaft ? 116 - Meaning of IPC ? 106 - Type of connection engine/MGB ? 117 - Meaning of TBO ? 107 - Number of engine drains ? 108 - Engine operating envelope ; min and max altitude pressure? 109 - Max starting altitude ? 110 - Power turbine max overspeed ?


118 - Is borescopic inspection of the combustion chamber possible ? 119 - Procedure in case of operation in super contingency rating ? 120 - Is there an adjustment of the torquemeter ?



ARRIEL 1

Training Manual

QUESTIONNAIRE 3 This multi-choice questionnaire is used to review, in a relatively short time, certain important points and to test the acquired knowledge. Answers to the questions can be found at the end of the questionnaire. 1 - The ARRIEL 1 engine is : a) a free turbine turboshaft engine b) a turbo-jet engine c) a fixed turbine turboshaft engine. 2 - Section of passage of the compressor diffusers : a) regular b) divergent c) convergent. 3 - Type of combustion chamber : a) annular with centrifugal injection b) annular, reverse flow c) annular, indirect flow. 4 - The power turbine nozzle guide vane belongs to : a) module M04 b) module M03 c) module M02. 5 - Type of exhaust pipe attachment : a) bolts b) mounting pads c) clamp.


6 - How many bearings support the gas generator : a) 4 b) 2 c) 3. 7 - The engine includes : a) a hot section and a cold section b) 5 modules c) 4 modules. 8 - Type of oil system : a) dry sump b) constant pressure c) lubrication by splashing. 9 - Setting of the oil filter pre-blockage indicator : a) lower than the by-pass valve b) higher than the by-pass valve c) the same as the pump valve. 10 - The oil strainers are located : a) at the outlet of the pumps b) on the inlet of the scavenge pumps c) at the inlet of the lubricated components. 11 - Is there a max oil temperature : a) yes, 60 °C b) no c) yes, 115 °C maxi.



ARRIEL 1

Training Manual

QUESTIONNAIRE 3 (continued)

12 - The air tapped at the centrifugal wheel outlet pressurises : a) some labyrinth seals b) the tank c) the pumps. 13 - Position of the bleed valve during flight ? a) open b) closed c) depends on conditions. 14 - Ventilation of start injectors : a) does not exist b) is made with air from the compressor c) is made with atmospheric pressure air. 15 - The injection centrifugal wheel is drained : a) permanently b) to enable the ventilation cycle c) during engine shut-down. 16 - The max speed of the gas generator is : a) limited by a hydraulic stop b) limited by a mechanical stop c) not limited by the Fuel Control Unit.


17 - The gap between the metering needle & the fork : a) represents the instant flow step b) varies with N1 c) provides a smoother acceleration. 18 - The fuel pump is : a) vane type b) gear type c) centrifugal. 19 - The fuel system pressurising valve : a) is electrically controlled b) operates when overpressure occurs c) gives priority to the start injectors. 20 - The starter is de-energised : a) automatically b) by air pressure c) manually. 21 - The thermocouples are wired : a) in series b) in parallel c) on the turbine casing.



ARRIEL 1

Training Manual

QUESTIONNAIRE 3 (continued) 22 - The torque indicating system : a) is hydraulic b) is not used c) is of phase displacement type.

28 - HE ignition means : a) Hot Electrode b) High Energy c) High Emission.

23 - Number of thermocouple probes : a) 3 b) 4 c) 5.

29 - Borescopic inspection is used to check : a) the external parts condition b) the condition of internal parts which are not accessible without removal c) the reduction gearbox condition.

5-a 10 - b 15 - c 20 - c 25 - b 30 - abc ?

Answers


4-b 9-a 14 - b 19 - c 24 - c 29 - b

27 - Starting is possible with one igniter : a) yes b) no c) yes, in emergency.

3-a 8-a 13 - c 18 - b 23 - a 28 - b

26 - The starter is supplied via a : a) relay b) micro switch c) transistor.

2-b 7-b 12 - a 17 - a 22 - a 27 - a

25 - Bleed valve position is transmitted by : a) a pressure switch b) a micro switch c) an RVDT.

30 - The reliability of the engine is : a) good b) fairly good c) extremely good.

1-a 6-c 11 - c 16 - b 21 - b 26 - a

24 - Max oil pressure ? a) 3 bars b) 6 bars c) 8 bars.



ARRIEL 1

Training Manual

QUESTIONNAIRE 4 2 - Name the reference stations :

This questionnaire is a sort of drill which is also used to test and perfect the knowledge acquired. 1 - Complete this table (with values) :

G

Max take-off power

C

T1

T2

........................ CC

Compression ratio

.......................

Engine air flow

.......................

N2 speed at 100 %

......................

N1 speed at 100 %

.......................


0

1

2

3

Q

4

5

0 - .................................

3

- ..................................

1 - .................................

4

- ..................................

2 - .................................

5

- ..................................



ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 3 - Engine description - Complete the legend of the diagram : 1

2

3

4

5

9

8

7

6

1 - ...................................................

2 - ......................................................

3 - .................................................

4 - ...................................................

5 - ......................................................

6-

................................................

7 - ...................................................

8 - ......................................................

9-

................................................




ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 4 - Oil system - Complete the legend of the diagram : AIRFRAME

4

ENGINE

2

1

5

3

6

1 - ...................................................

2 - ......................................................

3 - .................................................

4 - ...................................................

5 - ......................................................

6-


................................................



ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 5 - Complete the following table :

P0

P1'

P2

Injector ventilation Acceleration control unit Bleed valve control pressure Injection wheel pressurisation Axial compressor bearing pressurisation Gas generator rear bearing cooling Power turbine bearing chamber labyrinth pressurisation Gas generator turbine disc cooling




ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 6 - Complete the legend of the compressor field diagram :

COMPRESSION RATIO P2 / P0

A B

C

AIR FLOW G

A - ...................................................


B - ......................................................

C - .................................................



ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 7 - Fuel system - Complete the legend : 1

2

3

4

5

6

7

8

9

12

11

10

1 - ...................................................

2 - ......................................................

3 - .................................................

4 - ...................................................

5 - ......................................................

6-

................................................

7 - ...................................................

8 - ......................................................

9-

................................................

10 - ...................................................

11 - ......................................................

12 - ................................................




ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 8 - Control system - List the components :

1 2

3

8

P2

4 Q

7 + N1

6 +

N1*

N2

5 +

N2*

1 - ...................................................

2 - ......................................................

3 - .................................................

4 - ...................................................

5 - ......................................................

6-

7 - ...................................................

8 - ......................................................


................................................



Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 9 - Complete the following table :

Engine stopped

Engine in stabilised flight

Fuel pump .......................................................... Pump pressure relief valve ................................ Constant ∆P valve .............................................. Metering needle ................................................. Start injector electro-valve................................. Overspeed electro-valve .................................... Pressurising valve .............................................. Main valve ......................................................... Combustion chamber drain valve ......................




Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 10 - Complete the following graphs during a load C increase :

Power turbine speed N2

time

Load C Fuel flow Q

time

time Gas generator speed N1

time




ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (suite) 11 - Fuel system - List the components : 21

22

20

23

24

1 19 2 18

3

17

4 6

16

5

15

7

14

9 13 8 12

10

11

1 - ..........................

2 -

..........................

3 -

.........................

4 - ..........................

5 - ..........................

6 -

..........................

7 -

.........................

8 - ..........................

9 - ..........................

10 -

..........................

11 -

.........................

12 - ..........................

13 - ..........................

14 -

..........................

15 -

.........................

16 - ..........................

17 - ..........................

18 -

..........................

19 -

.........................

20 - ..........................

21 - ..........................

22 -

..........................

23 -

.........................

24 - ..........................




ARRIEL 1

Training Manual

QUESTIONNAIRE 4 (continued) 12 - Drain system - List the drains :

4

3

5

6

7

8

1

2

1 - ..........................

2 -

..........................

3 -

.........................

4 - ..........................

5 - ..........................

6 -

..........................

7 -

.........................

8 - ..........................




Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 13 - Complete the following table : Number of lifting points ? Type of fire detectors ? Number of drain points ? Air used for intake anti-icing ? Max air tapping flow for aircraft use ? Loss of power due to aircraft tapping ?

14 - List the main resources for on condition monitoring : 1 - .............................................................................................................. 2 - .............................................................................................................. 3 - .............................................................................................................. 4 - .............................................................................................................. 5 - .............................................................................................................. 6 - .............................................................................................................. 7 - .............................................................................................................. 8 - .............................................................................................................. For training purposes only © Copyright - TURBOMECA - 2000



Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 15 - Define of the following documents :

Maintenance manual

Spare parts catalogue

Tool catalogue

Service bulletin

Service letter

Engine log book

Flight manual




Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 16 - Maintenance procedures

1 - List 2 advisory notices of "warning" category. 2 - Time of non operation requiring long term storage. 3 - Compressor washing - Product and procedure. 4 - Procedure to rotate the power turbine for borescopic inspection. 5 - Location of the vibration sensor Installation. 6 - Type of attachment compressor bleed valve.

of

the

7 - Type of attachment of the fuel control unit.




Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 17 - Fault analysis. Indicate (briefly) the effects of the following faults. 1 - Dirty compressor. 2 - Fracture of the power shaft. 3 - Fracture of the accessory drive shaft. 4 - Obstruction of the power turbine pressurisation pipe. 5 - Blockage of the fuel filter element. 6 - Partial clogging of the centrifugal fuel injection wheel. 7 - Jamming of the constant ∆P valve. 8 - No electrical supply of the start injector valve. 9 - Fracture of the P2 pipe to the FCU. 10 - Fuel leak from the start purge valve.




Training Manual

ARRIEL 1

QUESTIONNAIRE 4 (continued) 18 - Trouble shooting. Indicate the probable cause(s) of the following faults. 1 - On start selection, N increases but not the gas temperature. 2 - On start selection, N and t4 increase but not sufficiently to obtain start. 3 - Surge of the compressor. 4 - Max power not obtained. 5 - On stop selection, the engine does not completely shut-down. 6 - Incorrect speed of the helicopter rotor. 7 - Power turbine overspeed. 8 - Drop of oil pressure. 9 - Abnormal t4 temperature. 10 - N1 overspeed.




END of this manual and (maybe also) of the course but n o t th e E N D o f y o u r tra in in g w h ic h mu s t b e co n tin u e d , ha rmon izin g k n o w led g e an d ex p e rie nc e . T H A N K Y O U fo r y o u r k in d atte n ti on . Au revoir Good bye Adiós Auf Wiedersehen Adeus Arrivederci Farvel To t z i e n s Adjö Näkemiin Antio Ma salaam

REMARKS Remarks (appreciations, criticisms, suggestions...) should be forwarded to : TURBOMECA CENTRE D'INSTRUCTION 40220 TARNOS - FRANCE

REMARKS CONCERNING THE TRAINING AIDS

REMARKS CONCERNING THE TRAINING COURSE

Name ....................................................................................................................................... . Address .................................................................................................................................... . Course .............................................................. from............................to ............................. .

TURBOMECA Training Centre

C E N T R E

D ' I N S T R U C T I O N

40220 TARNOS - FRANCE Tel: France .............................. 05 59 74 40 07 International ................. 33 5 59 74 40 07 Fax: France .............................. 05 59 74 45 16 International ................. 33 5 59 74 45 16 E-mail: [email protected] www.turbomeca-support.com

Arriel_1 12-00 En

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