Module 14 Propulsion For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk 1. From where is manifold pressure taken on a supercharged engine? a) Between the carburetor and the supercharger b) Between the supercharger and the throttle c) Between the carburetor and the induction ports 2. On a gas turbine engine, what is the fan driven by? a) HP turbine b) LP turbine c) IP turbine 3. What is an engine stage? a) One rotor plus one stator b) One IGV and one rotor c) One compressor rotor and one nozzle guide vane 4. The air data input to the FADEC fails. The result will be a) a lack of flight data b) uncorrected data from hard wired analogue analogue sensors is utilized c) the FADEC reverts to the failsafe mode 5. Torque measurement is taken from the a) free turbine shaft b) reduction gearbox c) prop shaft 6. A FADEC system consists of a) HMU, sensors and an EEC b) HMU, ADC and sensors c) EEC, ADC and sensors 7. What power supply is required for a thermocouple system to work? a) Direct current b) Alternating current c) Neither of the above 8. In a 24 thermocouple system, one thermocouple goes open circuit. What error is detected at the indicator? a) None b) No indication c) Gauge freezes at last known reading 9. In a thermocouple temperature sensing system, what is the purpose of the compensating resistor? a) To standardise the reading for different different engine types b) To correct for varying ambient temperatures at the cold junction c) To correct for varying ambient temperatures at the hot junction 10. In a dive, with the throttles fixed, the EPR will a) increase b) decrease c) not change 1
How did you do'? Question 1 The coned answer is c Read up on manifold pressure indication systems (The supercharger bills a red herring) Question 2 The correct answer is b Read up on basic gas turbine engine configurations Question 3 The correct answer is a Read up on basic gas turbine engine configurations Question 4 The correct answer is c Read up on FADEC Question 5 The correct answer is b Read up on torque indication systems Question 6 The correct answer is a Read up on FADEC Question 7 The correct answer is c Read up on EGT indication systems Question 8 The correct answer is a Read up on EGT indication systems Question 9 The correct answer is b Read up on EGT indication systems Question 10 The correct answer is c Read up ERR indicating systems
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How did you do'? Question 1 The coned answer is c Read up on manifold pressure indication systems (The supercharger bills a red herring) Question 2 The correct answer is b Read up on basic gas turbine engine configurations Question 3 The correct answer is a Read up on basic gas turbine engine configurations Question 4 The correct answer is c Read up on FADEC Question 5 The correct answer is b Read up on torque indication systems Question 6 The correct answer is a Read up on FADEC Question 7 The correct answer is c Read up on EGT indication systems Question 8 The correct answer is a Read up on EGT indication systems Question 9 The correct answer is b Read up on EGT indication systems Question 10 The correct answer is c Read up ERR indicating systems
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1. How is the N1 and N2 measured on a triple spool engine? a) Pulse type speed probes b) Tachometer connected to the external gearbox c) Tachometer connected to the internal gearbox 2. A twin spool engine has a) one turbine on one shaft b) two turbines on one shaft c) two turbines on two shafts 3. A free turbine aircraft engine is most likely to be used on a a) high bypass engine b) a direct coupled coupled engine c) a helicopter engine 4. Propeller speed is measured from a) a slip ring pulse probe b) a tachometer on the LP turbine shaft c) a pulse probe at the engine side of the reduction gear 5. Propeller torque is analogous to a) engine RPM b) shaft horsepower c) propeller RPM
6. How is power indicated on a fixed pitch propeller? a) RPM gauge b) Torque gauge c) Horsepower gauge 7. What are the units of manifold pressure on a normally aspirated engine? a) PSI b) Inches of water c) Inches of mercury 8. In a FADEC what is the result of Channel A failing to receive information from a sensor? a) Channel B will assume control b) Channel A will take the information from channel channel B c) Channel A will take the information from the backup sensor 9. A synchro pressure measuring system requires a) alternating current b) direct current c) either ac or dc 10. A synchro pressure measuring system works on the principle of changes in pressure related to changes in a) frequency b) voltage c) flux 3
How did you do'? Question 1 The coned answer is a Read up on basic gas turbine engine configurations Question 2 The coned answer is c Read up on basic gas turbine engine configurations Question 3 The co reel answer is c Read up on basic gas turbine engine configurations-a tree turbine allows Ice rotor to be stopped whilst the engine is running Question 4 The correct answer is a Read up on propeller speed indicating systems Question 5 The correct answer is b Read up on torque indicating systems Question 6 The correct answer is a Read up on fixed pitch propeller/engine indicating systems Question 7 The correct answer is c Read up on piston/propeller indicating systems Question 8 The correct answer is b Read up on FADEC Question 9 The correct answer is a Read up on synchro systems - see also module A Question 10 The correct answer is c Read up on synchro systems - see also module A Your total score is 0 Comment A trained chimp could do better! Best you give up now
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1. Pure jet engines use a) stagnation thermocouples b) rapid response c) variable resistance thermocouples 2. Modern oil pressure servo transmitters sense a) differential pressure b) absolute pressure c) HP oil pressure 3. EGT thermocouples are usually made of a) nickel and platinum b) chromel and platinum c) chromel and alumel 4. Thrust is generated in a turboprop system by a) moving a small mass of air quickly b) moving a large mass of air quickly c) moving a large mass of air slowly 5. Power is adjusted in a variable pitch turboprop aircraft by a) increasing RPM b) increasing fuel flow c) increasing pitch For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk 6. Thrust in a high bypass engine is measured by measuring a) N3 RPM b) fuel flow c) neither of the above, thrust is not indicated in flight 7. EPR is a ratio of a) P1 to P4 b) P1 to P fan c) P1 to P6 8. The majority of power in a free turbine engine is used to a) drive the gas generator b) drive the free turbine c) expel gases through the exhaust 9. The total power in a turboprop engine is the a) SHP b) ESHP c) BHP 10. To measure oil temperature, which of the following would most likely be used? a) Resistance temperature measurement b) Thermocouple measurement c) Optical pyrometer
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Question 1 The correct answer is a When you think of he difference in speeds of the jet efflux -on a pure jet and say, a turbofan engine, Then you will understand why a pure jet needs stagnation thermocouples lo slow the gas flow at the sensor Question 2 The correct answer is a Read up on oil pressure sensors Question 3 The correct answer is c Read up on Thermocouples Question 4 The correct answer is c Read up on basic propulsion Theory Question 5 The correct answer is b Increasing fuel flow attempts lo increase RPM, but the governor resets the pitch to a higher settingmaintaining RPM but at a higher thrust Question 6 The correct answer is c Thrust cannot be measured directly (not in flight anyway), so the fan speed is used as an 'indication' of thrust since it varies approximately linearly with thrust Question 7 The correct answer is b ERR is the ratio of output pressure lo input pressures of a gas turbine engine Unless you know how many stages There are, you cannot say whether it is PI lo P4 or to P6 etc But a turbofan engine uses The ratio of pressures across The fan Question 8 The correct answer is b About 85% of the power in the gas from the gas generator is used to drive The propeller (i.e. via The free turbine) Question 9 The correct answer is b Equivalent Shaft Horsepower (ESHP) is The addition of Shaft Horsepower (The propeller shaft) and the thrust of the exhaust efflux (with a little conversion factor involved) Question 10 The correct answer is a Read up on oil temperature measurement Your total score is 0 Comment A trained chimp could do better ! Best you give up now l
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1. Pure jet engines use a) stagnation thermocouples b) rapid response c) variable resistance thermocouples 2. Modern oil pressure servo transmitters sense a) differential pressure b) absolute pressure c) HP oil pressure 3. E.G.T. thermocouples are usually made of a) nickel and platinum b) chromel and platinum c) chromel and alumel 4. Thrust is generated in a turboprop system by a) moving a small mass of air quickly b) moving a large mass of air quickly c) moving a large mass of air slowly 5. Power is adjusted in a variable pitch turboprop aircraft by a) increasing RPM b) increasing fuel flow c) increasing pitch
6. Thrust in a high bypass engine is measured by measuring a) N3 RPM b) fuel flow c) neither of the above, thrust is not indicated in flight 7. EPR is a ratio of a) P1 to P4 b) P1 to P(fan) c) P1 to P6 8. The majority of power in a free turbine engine is used to a) drive the gas generator b) drive the free turbine c) expel gases through the exhaust 9. The total power in a turboprop engine is the a) SHP b) ESHP c) BHP 10. To measure oil temperature, which of the following would most likely be used? a) Resistance temperature measurement b) Thermocouple measurement c) Optical pyrometer
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Question 1 The correct answer is a When you think of he difference in speeds of the jet efflux -on a pure jet and say, a turbofan engine, Then you will understand why a pure jet needs stagnation thermocouples lo slow the gas flow at the sensor Question 2 The correct answer is a Read up on oil pressure sensors Question 3 The correct answer is c Read up on Thermocouples Question 4 The correct answer is c Read up on basic propulsion Theory Question 5 The correct answer is b Increasing fuel flow attempts lo increase RPM, but the governor resets the pitch to a higher settingmaintaining RPM but at a higher thrust Question 6 The correct answer is c Thrust cannot be measured directly (not in flight anyway), so the fan speed is used as an 'indication' of thrust since it varies approximately linearly with thrust Question 7 The correct answer is b ERR is the ratio of output pressure lo input pressures of a gas turbine engine Unless you know how many stages There are, you cannot say whether it is P1 to P4 or to P6 etc But a turbofan engine uses The ratio of pressures across The fan Question 8 The correct answer is b About 85% of the power in the gas from the gas generator is used to drive The propeller (i.e. via The free turbine) Question 9 The correct answer is b Equivalent Shaft Horsepower (ESHP) is The addition of Shaft Horsepower (The propeller shaft) and the thrust of the exhaust efflux (with a little conversion factor involved) Question 10 The correct answer is a Read up on oil temperature measurement Your total score is 0 Comment A trained chimp could do better ! Best you give up now l For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk
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1. The principle of operation of a DC ratio meter is a) one coil moving in a uniform magnetic field b) two coils moving in a uniform magnetic field c) two coils moving in a non-uniform magnetic field 2. A thermocouple indicator is basically a a) mill voltmeter b) milliohmeter c) milliameter 3. If a FADEC loses its ADC input, in the short term it will a) go into soft redundancy b) go into hard redundancy c) go to limit protection mode 4. With an aircraft with a fixed pitch propeller, what indication has the pilot got of the output power? a) fuel flow b) oil pressure c) engine speed indicator 5. The primary purpose of an EEC is a) to change analogue inputs into digital format to provide glass cockpit information and reduce flight crew workload b) to change analogue inputs into digital format to reduce flight crew workload and provide maintenance information c} to save fuel. reduce crew workload and reduce maintenance costs
6. If a tacho generator indicated in reverse, the probable cause is a) wrong input frequency b) two phases cross connected c) supply and transmitter cross connected 7. A sensing element goes open circuit in a ratio meter. What will be happen? a) Temperature indicates below ambient b) Full scale deflection c) Hairspring takes indicator off scale 8. A thermocouple is constructed of a) two dissimilar metals welded together b) two dissimilar metals with an air gap between them c) three dissimilar metals welded together 9. A thermocouple indication is taken from the a) hot junction b) cold junction c) difference between the hot junction and the cold junction 10. On a twin spool engine, the HP compressor is driven by a) ram air over the compressor 9
b) early stages of the turbine c) later stages of the turbine
How did you do'? Question 1 The correct answer is c E 1-1 J Pallet Aircraft Instruments and Integrated Systems page 31 G refers Question 2 The correct answer is a E H J Pallet Aircraft Instruments and Integrated Systems page 323 refers Question 3 The correct answer is a Soft redundancy is also known as the Alternate Mode Question 4 The correct answer is c RPM or Manifold pressure are The only indications of power in a fixed pitch propeller/engine Question 5 The correct answer is c The FADEC system provides greater operating and maintenance efficiency Question 6 The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 348 refers (ills also The same As with an AC motor) Question 7 The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 318 refers Question 8 The correct answer is a Commonly Alumel and Chromel in GTE applications Question 9 The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 320 refers Question 10 The correct answer is b The HP Compressor is always driven by the turbine nearest the combustion chamber
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1. In a multiple probe thermocouple system, what is the effect if one probe fails? a) No noticeable effect b) Reduction in temp reading c) Increase in temp reading 2. In a gas turbine if air is tapped from the H.P bleed a) EPR decreases and EGT increases b) EPR stays constant and EGT decreases c) EPR increases and EGT decreases 3. The vane on a vane type fuel flow measuring device becomes stuck. What safety backup is available for the engine fuel flow? a) A fuel bleed valve b) A bypass valve c) A differential pressure bypass valve 4. In a FADEC engine with a hydro mechanical fuel system, how is fuel flow controlled? a) By fuel pressure b) By electro-hydraulic servo valves (EHSVs) c) By oil hydraulics 5. In the HEIU the discharge resistors a) allows sufficient voltage to be stored to provide relight facilities up to 55,000 ft. b) protects the unit from excessive voltages. c) allows the capacitors to discharge when the unit is switched off.
6. A modular constructed gas turbine engine means that a) its major assemblies can be removed and replaced b) all engines have a specific component layout c) the engine is constructed by the vertical assembly technique 7. The purpose of a high bypass ducted fan engine is to a) improve efficiency b) improve thrust c) reduce size 8. When using a test set to test an EGT thermocouple circuit a) no compensation for ambient temperature is required b) only consider ambient temperature compensation if the ambient temperature is over2u°C c) always compensate for ambient temperature
9. Where is EGT measured? a) In the combustion chamber b) Downstream of the combustion chamber c) Upstream of the combustion chamber 10. How does a boost gauge compensate for altitude changes? a) Spring sealed bellows b) Two bellows against atmospheric pressure c) There is no compensation 11
How did you do'? Question 1 The correct answer is a All thermocouples are connected in parallel therefore the loss of one will not affect the output voltage Question 2 The correct answer is a Jeppessen Gas Turbines page 8-7 refers to a shift in EPR Also note that a standard test of bleed valves opening is an increase of EGT is observed Question 3 The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 3G9 refers Question 4 The correct answer is b. All FADEC engines have a hydro-mechanical unit within which are contained EHSVs Question 5 The correct answer is c Rolls Royce The Jet Engine Page 129 refers Question 6 The correct answer is a Rolls Royce The Jet Engine page 2G5 refers Question 7 The correct answer is a Rolls Royce The Jet Engine page 17 refers Question 8 The correct answer is a All EGT systems have automatic cold junction compensation See EHJ Pallet Aircraft Instruments and Integrated Systems page 322 Question 9 The correct answer is b EGT is exhaust gas temperature therefore it is after the combustion system Question 10 The correct answer is a Read up on the manifold pressure gauge-Pallet Aircraft Instruments and Integrated Systems Pg 35G
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1. An EMF is produced by a thermocouple. This is sensed a) at the hot junction b) at the cold junction c) between the hot and cold junctions 2. Supervisory EEC sends its output to the a) fuel valve b) HMU/FFG c) EGT thermocouple circuit 3. Ratiometer pointer movement is achieved by a) one coil providing a torque against a permanent magnet b) two opposing coils providing a torque in a varying magnetic field c) two opposing coils providing a torque in a permanent magnetic field 4. A fuel flow transmitter requires a motor or a synchronous motor to have a a) constant voltage within small tolerances b) constant frequency within small tolerances c) low EMF as it is immersed in fuel 5. A boost gauge measures a) absolute pressure on the inlet port b) brake mean effective pressure c) gauge pressure at the injector For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk 6. On a thermocouple circuit on a non FADEC engine, what is the purpose of the ballast resistor? a) To compensate for ambient temperatures b) To standardise both engine's EGT readings c) To compensate for altitude 7. Boost pressure is measured in a) inches of Hg b) inches of water c) PSI 8. Power is adjusted in a gas turbine engine by a) increasing airflow to the combustion chamber b) increasing air and fuel flow c) increasing fuel flow 9. The EPR reading is taken from a ratio of a) jet pipe pressure to compressor inlet pressure b) compressor delivery pressure to compressor inlet pressure c) turbine inlet pressure to compressor delivery pressure 10. The basic gas turbine engine cycle is a) induction, compression, combustion, expansion, exhaust b) induction, compression, expansion, combustion, exhaust c) compression, combustion, induction, expansion, exhaust 13
How did you do'? Question 1 The coned answer is b Read up on The Thermocouple operation Question 2 The coned answer is b Read up on EEC Question 3 The correct answer is c Read up on The ratio meter Question 4 The correct answer is b Read up on fuel flow transmitters Question 5 The correct answer is a Read up on The boost gauge Question 6 The correct answer is b Read up on The Thermocouple operation Question 7 The correct answer is a CAPS leatlelAL/10-3 states that the boost pressure can be measured in in Hg orlbt/in2leaflet EL/'M Para 13 2 quotes over boost figures in both Also Pallet aircraft Instruments &. Integrated Systems Pg 355-357 mentions both Worth making a comment on the exam answer paper if you get this Question Question 8 The correct answer is c Fuel flow is adjusted, which in turn increases The airflow and hence power output Question 9 The correct answer is a Read up on EPR indication systems Question 10 The correct answer is a Read up basic gas turbine engine Theory
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1. The high bypass duct a) drives a cabin air compressor b) provides engine cooling c) improves propulsive efficiency 2. If an engines fadec system loses air data permanently the pilot will a) select alternate pilot static b) switch to alt on the relevant EEC c) turn that EEC off 3. An EPR system reads slightly over 1, this would mean a) the transmitter datum point has moved and needs replacing b) no action required this is normal c) the indicator needs re-calibrating back to 1 4. Manifold pressure is measured a) at inlet port above and below ambient conditions b) at inlet port above and below standard atmosphere at sea level c) at inlet port indicating boost pressure 5. A temperature indicating system incorporating a resistance bulb on a selected range has pointer movement a) proportional to bulb resistance b) inversely proportional to bulb resistance c) resistance does not affect pointer movement
6. In a ducted fan engine, the fan is driven by the a) accessory gearbox b) turbine c) air passing over the compressor 7. In a FADEC system, active control switchover occurs a) on shutdown b) when channels A and B are healthy c) on engine startup only 8. Gas turbines work on the a) otto cycle b) brayton cycle c) diesel cycle 9. Oil systems consists of a) 2 systems b) 3 systems c) 4 systems 10. With the EEC in control the throttle levers are always a) in the fully forward position b) in the fully aft position c) anywhere between the fully fwd and fully aft positions How did you do'? 15
Question 1 The coned answer is c Read up on advantage of high bypass ratio Question 2 The correct answer is a This is retelling lo The 7G7 CFG engine This is known as soft reversionary mode Engine uses last known T12 data Pressing The ALTN light switch puts it into hard reversionary mode where it will use ISA conditions (on both engines) Question 3 The correct answer is b Engine Pressure Ratio (EPR) is The radio of turbine output pressure to compressor input pressure It is normal for it to be more than 1 Question 4 The correct answer is a When The engine is not running, The manifold pressure gauge will indicate ambient conditions Question 5 The correct answer is a As the temperature increases, The resistance increases-therefore 'directly proportional' Question 6 The correct answer is b Read up on engine configurations Question 7 The correct answer is a on the CF6 FADEC, each startup uses an alternative channel But the switch over occurs on shutdown of the previous run The reason for it is that a switch over on startup might interrupt the startup sequence Question 8 The correct answer is b Gas turbines work on the Brayton Cycle Piston engines work on The Otto cycle Question 9 The correct answer is b An oil system has 3 sub-systems Suction, Pressure and Scavenge Question 10 The correct answer is c The pilot sets the throttle to any position and The EEC controls to that commanded setting
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1. Turboprop thermocouple probes are a) rapid response b) stagnation c) surface mounted 2. Propelling nozzle provide a) pressure thrust b) velocity thrust c) pressure and velocity thrust 3. How are the combustion chambers cooled? a) By l.p compressor air b) By h.p compressor air c) By fan pressure air 4. Fan blade speed is measured by a) phonic wheel b) drag cup and tachometer c) eddy currents 5. Fadecs operate by a) 2 controlling 1 operating b) 1 controlling 1 operating c) 2 units each capable of independent control
6. When a thermocouple fails, the temperature reading will a) over read b) under read c) stay the same 7. An aircraft flying at 500rnph would typically use a) turbojet b) turbofan c) turboprop 8. The inlet of a turbo fan is a) divergent b) convergent c) convergent-divergent 9. What is the pressure increase over one stage of a centrifugal compressor? a) 5:1 b) 1.2:1 c) 8:1 10. The bleed valve on a engine at start up is a) open b) closed c) modulating How did you do'? 17
For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk Question 1 The correct answer is a Turboprop Thermocouples are rapid response This is because the gas flow is low speed in a turboprop exhaust Question 2 The correct answer is c A propelling nozzle is used where gas flows are al sonic speed, and thus produce pressure thrust a swell as Velocity thrust Question 3 The correct answer is b About 60% of the air exiting the compressor (HP compressor air) is used for cooling the combustion chamber and dilution of the flame Question 4 The correct answer is a Since The tan does not normally drive The gearbox", a phonic wheel and an impulse pickup is used to measure the speed Question 5 The correct answer is c FADECs have 2 independent systems, each capable of controlling The engine Question 6 The correct answer is c Thermocouples on a large engine EGT systems are wired in parallel and The indicators a voltmeter Therefore it one Thermocouple tails, The voltage across The indicator will not change However The reading will be less accurate due to a lower sampling of the temperature Question 7 The correct answer is a 500mph is supersonic Supersonic aircraft are powered by a turbojet Question 8 The correct answer is a A turbofan engine has a divergent engine lo convert: airspeed into a pressure rise (ram pressure recovery) Question 9 The correct answer is a centrifugal compressor has a pressure ratio of About 5:1 (per stage) An axial compressor has a pressure ratio of About 1.2:1 (per stage) Question 10 The correct answer is a Choking of a compressor normally occurs on startup, Therefore The bleed valves are open at this time to prevent choking and subsequent surge
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1. EPR is measured between inlet and a) jet pipe b) cold and hot exhaust c) front of turbine 2. One stage of a turbine is a) n.g.v then turbine blade b) turbine blade then n.g.v c) i.g.v then turbine blade 3. In a flow type fuel system, fuel shutoff is done by a) mechanical ball valve b) FCU torque motor c) l.p fuel cock 4. The fuel flow transmitter is downstream of a) pr sov b) h.p pump c) l.p pump 5. How is fuel flow varied in a variable displacement pressure type pump? a) Alter the cam plate angle b) Remote servo pressure c) Direct cable to cam plate
6. Advantage of flow type over pressure type is a) it has lower pressure so greater reliability b) it can take into account rpm, pressure (ambient) and e.g.t. c) has no need for fly weights and governors 7. When the full authority fuel control unit is changed, the rating plug a) stays with the engine b) stays with the FAFC c) is replaced every time 8. The EEC is powered and able to operate via a) only a dedicated alternators b) the aircraft electrical system c) The EEC is capable of being powered by both independently depending on conditions 9. The EEC uses a) ARINC 429 formatted data b) ARINC 629 formatted data c) uses neither ARINC 429 or 629 formatted data 10. The fuel metering unit has direct inputs via a) only the EEC b) the EEC and the fire control handle c) the EEC, fire control handle and the engine master switch Question 1 19
The correct answer is a EPR is the engine pressure ratio of engine inlet to jet pipe pressures Question 2 The correct answer is a One sage of a turbine includes one guide vane (stator) + turbine (rotor) Question 3 The correct answer is a Fuel shut of is done with a valve incorporated with The throttle Question 4 The correct answer is c Fuel Flow Transmitters downstream of the LP pump but before the HP pump and pressure regulating shut off valve (pr sov) - Ret RR Jet Engine pg 113 Question 5 The correct answer is a Fuel flow is varied by altering The cam-plate angle (greater angle produces a greater stroke lo The pistons) However cam pi ale angle is controlled by The servo pressure, so Question is a little dubious Question 6 The correct answer is b The flow type fuel system can take into account rpm ambient pressure, EGT and other variables Ret RR Jet Engine pg 103 Question 7 The correct answer is a The rating plug provides discrete engine information to the
EEC Therefore The plug slays with The engine Question 8 The correct answer is c 28VDC bus is required on start The dedicated generator
lakes over as N2 or N3 increases (changeover occurs before 20%) Question 9 The correct answer is a ARINC429 is The standard data bus for all Boeing /airbus
engine systems Question 10 The correct answer is c The pilot must retain control of non normal and fire
shutdowns
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1. The optimum turbine speed is defined as a) the most efficient speed of the turbine b) 100% rpm of the engine c) 95 % rpm of the engine 2. An increase in fuel flow through the impeller type fuel flow transmitter is measured by a) drum lags impeller b) impeller lags turbine c) decreasing angle between the two 3. No power to EGT is indicated by a) yellow flag in front counter b) bug moves in the x direction c) bug moves in the y direction 4. Connection to a tachogenerator a) 3 phase star b) 3 phase delta c) 2 phase star For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk 5. A short circuit in a d.c ratio meter will give a) max scale reading b) zero scale reading c) min scale reading
6. An open circuit in a d.c ratio meter will give a) max scale reading b) zero scale reading c) min scale reading 7. A compressor shaft rotates on a) sintered bearings b) ball and roller bearings c) plain bearings 8. The EEC changes power settings by a) changing the throttle lever angle b) changing the fuel flow input c) changing the airflow input
9. A torque pressure measuring indicator is fed by a) direct oil pressure b) differential pneumatic pressure c) servo operated 10. The tachogenerator output has: a) A fixed frequency 21
b) A Variable frequency c) A DC Current output Question 1 The correct answer is a Answer A is coned by elimination 100% is not a maximum and whilst 95% might be the most efficient (optimum) RPM for one engine type it will not before another Question 2 The correct answer is b Pallet Aircraft Instruments 2nd edition page 334 refers The reference shows The impellor lagging the turbine greater speed gives
greater lag NB some references use The word rotor instead of impellor Question 3 The correct answer is a Pallet Aircraft Instruments 2nd edition page 293 refers Question 4 The correct answer is a Pallet Aircraft Instruments 2nd edition fig 10 13 el al refers Question 5 The correct answer is c Pallet Instruments and Integrated systems Peters Page 318Ashorlwill remove all power from both windings and The pointer will go to minimum scale Question 6 The correct answer is a CAAIPS (Old edition)AL10-Para11-10 states: An open circuit in the temperature sensing bulb or signal line will be indicated by max scale deflection Also see Pallet Instruments and Integrated systems Question 7 The correct answer is b Jeppessen Aircraft gas turbine Power plants Page 5-33 Question 8 The correct answer is b Jeppessen Aircraft gas turbine Power plants Page 7-17 Question 9 The correct answer is a Pallet Instruments and Integrated Systems Page 357 Question 10 The correct answer is b The faster the engine goes The faster The tacho generator goes
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1. On a fuel flow measuring device located on the engine a) no adjustments can be made b) external adjustments can be made for maximum rate fuel flow c) external adjustments can be made for minimum rate fuel flow 2. Where is the hot junction of a EGT thermocouple system found? a) In the indicator b) Upstream of the combustion chamber c) Downstream of the combustion chamber 3. The fan on a turbofan engine is turned by a) induction of the air across the fan into the compressor b) the turbine section c) the combustion chamber gases 4. When terminating connections for a EGT sensing system a) ensure that the pins and sockets are correctly crimped and brazed b) ensure that all connections are silver soldered c) ensure that the pins and sockets are of the same material as the leads 5. An EPR gauge indicates '1'. You should a) adjust the indicator back to zero b) replace the indicator, there is no adjustment c) do nothing this is what it should read with the engine shut down.
6. A Gas Turbine's propulsion force is produced by a) reaction of the rearward moving gasses b) impingement of the gasses on the surrounding air c) induced airflow into the engine 7. In a single spool gas turbine engine the compressor rev/min is a) more than the turbine speed b) less than the turbine speed c) equal to the turbine speed 8. A tacho pointer is moved by a) drag cup coupling b) ac servo motor c) synchronous motor 9. In a twin spool engine a) the HP turbine drives both LP and HP compressors b) the LP turbine drives the LP compressor and the HP turbine drives the HP compressor c) the HP turbine drives the LP compressor and the LP turbine drives the HP compressor 10. Relative permeability of fuel is also known as a) density of the fuel b) weight of the fuel c) dielectric constant of the fuel Question 1 23
The correct answer is a Pallet Aircraft Instruments and Integrated Systems Page 3G8-375 shows no on engine adjustment Question 2 The correct answer is c EGT stands for 'exhaust gas temperature 'Pallet Aircraft Instruments and Integrated Systems Page 320 refer Question 3 The correct answer is b See Rolls Royce The Jet Engine Page 5 Question 4 The correct answer is c Pallet Aircraft Instruments and Integrated Systems Page 32A refers Question 5 The correct answer is c With the engine shutdown pressure al the intake and aft of the turbine is the same Question 6 The correct answer is a Newton’s Third Law- Every action has an equal and opposite reaction Question 7 The correct answer is c See Rolls Royce The Jet Engine Page 5 In a single spool engine There is just a single speed for all rotating assemblies Question 8 The correct answer is a Pallet Aircraft Instruments and Integrated Systems Page 349 refers Question 9 The correct answer is b See Rolls Royce The Jet Engine Page 5 The HP spool is either side of the combustion chamber Question 10 The correct answer is c Pallet Aircraft Instruments and Integrated Systems Page 328 refers
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1. The cycle of a gas turbine engine is a) completed in one revolution of engine. b) completed in two revolution of the engine. c) continuous 2. Engines having two independent moving systems are a) compound engines b) twin spool engines c) complex engines 3. Compression ratio of compressor of gas turbine Engine is a) outlet pressure to Inlet pressure. b) measured across all rotor stages of compressor c) mass of airflow to combustion. 4. Torque pressure indication to measure power output of an engine is a) used in all Gas Turbine engines. b) not used in Gas Turbine engines. c) only used when engine output pressure is used for torque not for thrust. For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk 5. Manifold pressure is measured in a) direct absolute pressure in Bars b) differential pressure in mill bars c) direct absolute pressure in inch of Hg
6. Typically a torque pressure indication system is a) differential pressure type b) remote synchronous type c) direct Oil Pressure sensing type 7. A tachometer used to measure Rev/Min in turbine engines a) develops its own power for the system b) 28V dc is required c) 115V ac is required 8. Primary power for electronic engine control a) 115V ac essential bus. b) on side 115V ac bus bar supply. c) Permanent Magnet Alternator 9. Leads to measure thermocouple temperature are a) calibrated for circuit in used and cannot be shortened b) affected by Magnetic and electrical interference c) insulated by heat legging device to reduce errors in the indication end 10. A thermocouple sensing system test set requires a) a serviceable battery b) No power c) 24V dc 25
Question 1 The correct answer is c The Brayton cycle is a continuous cycle -A major advantage over the Otto Cycle (Piston Engine) Question 2 The coned answer is b The 2 spools are known as LP Spool and HP spool Question 3 The correct answer is a Rolls Royce The Jet Engine Page 25 refers Question 4 The correct answer is c Torque is used to measure power in turbo prop aircraft Question 5 The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 355 Question 6 The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 357 Question 7 The correct answer is a It develops an alternating current proportional to the speed of the engine Question 8 The correct answer is c Driven by The Engine's High Speed external Gearbox", it provides a discrete power supply for the engine Question 9 The correct answer is a A&P Power plant Handbook EA-AC-65-12A page 494(4} refers Question 10 The correct answer is a A&P Powerplant Handbook EA-AC-65-12A page 494 refers
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1. The HP compressor is powered by a) the first set of turbines b) the last set of turbines c) the intermediate compressor 2. Torque is measured in gas turbine engines a) never b) where there is a free turbine providing the power c) on small pure jet engines 3. What is the supply voltage to tacho generators? a) 28vdc b) 115vac c) It has no supply 4. A FADEC takes measurements of engine speed, a) temperature and pressure b) temperature c) pressure 5. The fuel metering valve in the hydro mechanical unit of a FADEC system is operated by a) hydraulic servo pressure b) fuel servo pressure c) electrical servo
6. Boost pressure is a) atmospheric above ambient b) atmospheric below ambient c) the absolute of the manifold chamber 7. To check/test a temperature indicator you would a) connect a decade box in place of the temperature sensing element b) connect a decade box in series with the temperature sensing element c) connect a decade box in parallel with the temperature sensing element 8. Calibration for a ratiometer type temperature indicator takes into account a) the material of the coils b) the material of the sensing element c) the type of representation on the dial 9. Reverse thrust can only be selected when the throttle is a) 75% power position. b) open. c) at the idle stop 10. On a FADEC engine the EEC a) has electronic control of the hydro-mechanical fuel control unit in all modes b) has electronic control of the hydro-mechanical fuel control in some modes c) has mechanical control of the hydro-mechanical fuel control system Question 1 The correct answer is a The HP Compressor spool has the shortest shaft 27
Question 2 The correct answer is b A Free turbine always powers a shaft or propeller Question 3 The correct answer is c The Tacho generates its own voltage Question 4 The correct answer is a All three are need to determine The fuel flow.. and the rate of acceleration Question 5 The correct answer is b CFG course notes show that fuel is used to drive The FMV Question 6 The correct answer is c EHJ Pallet Aircraft instruments and Integrated Systems page 356 Question 7 The correct answer is a By replacing The sensor with a known resistance you can simulate temperature increase See Question 8 below Question 8 The correct answer is b RTD's use platinum or nickel wire see EHJ Pallet Integrated Instruments page 409 table 3 Question 9 The correct answer is c A mechanical interlock on The Throttle slops The reverse thrust lever from moving it fwd thrust is anything but idle Question 10 The correct answer is a The HMU is The interlace between The EEC and the fuel distribution system
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1. EPR is a measure of a) exhaust pressure compared to compressor inlet pressure b) exhaust pressure compared to combustor pressure c) combustion pressure compared to compressor inlet pressure 2. What exactly does a thermocouple measure? a) The difference between the hot and cold junction. b) Hot junction temperature. c) Cold junction temperature. 3. In a temperature sensing ratio meter what determines the actual temperature? a) The material of the sensor b) The material of the sensing coil c) The material of the balancing coil 4. Torque is a useful measure a) on engines where a portion of thrust produces torque b) on engines which only produce thrust c) on all engines 5. Boost pressure is a measure of a) manifold pressure b) atmospheric pressure plus turbocharger inlet pressure c) atmospheric pressure less turbocharger inlet pressure
6. The test switch of a continuous loop fire detector gives a a) continuity check b) bonding check c) insulation check 7. What are the types of continuous fire detection system? a) Capacitive and resistive b) Capacitive c) Inductive and capacitive 8. During normal running conditions a) combustion is continuously supported by ignition b) combustion is intermittently supported by ignition c) combustion is self supporting 9. What indication does the pilot receive that thrust reversers have deployed ? a) A feeling of rapid deceleration b) An audible warning c) A sequence of lights 10. On a fixed pitch propeller single engine aircraft, what is indicated as a measure of power? a) Oil pressure b) Engine speed c) Cylinder head temperature Question 1 29
