WEMG December 2007

UNCLASSIFIED

THIS DOCUMENT IS THE PROPERTY OF HER BRITANNIC MAJESTY’S GOVERNMENT

MARITIME ACQUISITION PUBLICATION No 01-020

MAP 01-020 WARSHIP ENGINEERING MANAGEMENT GUIDE Issue 01

December 2007

© CROWN COPYRIGHT 2007 Sponsored by: DE&S SE Sea - Surface Ship Ship Division, Defence Equipment & Support, MoD Abbey Wood, Bristol, BS34 8JH [email protected] Telephone 0117 91 35761

UNCLASSIFIED

MAP 01-020 Warship Engineering Management Guide

1

INTRODUCTIO INTRODUCTION N ................................ .............................................. .............................. ................................. ................................. ................................ .................... .... 1 1.1 1.2 1.3 1.4 1.5

2

Aim.........................................................................................................................................................1 Scope.....................................................................................................................................................1 Document Structure........................... Structure................................................................................ .................................................................................................... ............................................... 1 Key Concepts ............................................ ................................................................................................. ............................................................................................2 .......................................2 Future Updates to the WEMG ................................................ ..................................................................................................... ...............................................................5 ..........5

WARSHIPS IN MOD ACQUISITION .................. ........ .................... ................... .................. .................... ...................... ..................... ................. ....... 6 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9

3

Aim.........................................................................................................................................................6 Lines of Development................ Development..................................................................... ....................................................................................................... .......................................................6 .....6 Requirement Management............................................................. Management...... ......................................................................................................... .....................................................10 ...10 Acceptance Management.................................. Management......................................................................................... ..................................................................................13 ...........................13 Information Management................................................................ Management..................................................................................................................... ..................................................... 14 Risk Management.............................................. Management..................................................................................................... ..................................................................................15 ...........................15 Cost and Time ........................................... ................................................................................................ ..........................................................................................16 .....................................16 Through Life Management ..................................................... ............................................................................................................ .............................................................17 ......17 Organisational Structure & Responsibilities .................................................... ........................................................................................18 ....................................18

WARSHIP ENGINEERING MANAGEMENT .................. ......... .................... ..................... ................... .................. .................... .............. ... 22 3.1 3.2 3.3 3.4 3.5

4

Aim.......................................................................................................................................................22 Warship Characteristics............................................. Characteristics.................................................................................................... ..........................................................................22 ...................22 Management of Transversals................................................. Transversals ................................................................................................... .............................................................40 ...........40 Standards ................................................. ......................................................................................................... ...........................................................................................49 ...................................49 Warship Project Activities .................................................. ......................................................................................................... ..................................................................54 ...........54

THE PROGRESSION OF A WARSHIP PROJECT ................... ......... .................... ................... .................. .................... .............. ... 67 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14

Aim.......................................................................................................................................................67 Overview..............................................................................................................................................67 The Design Review ........................................... .................................................................................................. ..................................................................................68 ...........................68 Candidate Selection ...................................................... ............................................................................................................ ......................................................................69 ................69 Option Identification................................................... Identification. ......................................................................................................... ..........................................................................72 ...................72 Design Survey ........................................... ................................................................................................ ..........................................................................................75 .....................................75 Outline Capability Design Assessment .................................................. ............................................................................................... .............................................85 85 System Design................................................... Design.......................................................................................................... ..................................................................................87 ...........................87 Contract Design ......................................... .............................................................................................. ..........................................................................................88 .....................................88 Production Design ............................................. .................................................................................................... ..................................................................................90 ...........................90 Production............................................................................................................................................94 Acceptance ................................................ .................................................................................................. ..........................................................................................95 ........................................95 In-service ........................................... ................................................................................................ ................................................................................................ ...........................................101 101 Assessing warship project project maturity ................................................ ................................................................................................... ................................................... 102

5

ACRONYMS AND GLOSSARY ................... ......... ................... .................. ................... ..................... ...................... ...................... ................... ........ 129

6

REFERENCES & BIBLIOGRAPHY.......... BIBLIOGRAPHY.................... .................... ................... .................. ................... ..................... .................... .............. ..... 133 6.1 6.2

References ................................................ .................................................................................................. ........................................................................................133 ......................................133 Bibliography.......................................................................................................................................133

WEMG Issue 01

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December 2007

MAP 01-020 Warship Engineering Management Guide

1

INTRODUCTIO INTRODUCTION N ................................ .............................................. .............................. ................................. ................................. ................................ .................... .... 1 1.1 1.2 1.3 1.4 1.5

2

Aim.........................................................................................................................................................1 Scope.....................................................................................................................................................1 Document Structure........................... Structure................................................................................ .................................................................................................... ............................................... 1 Key Concepts ............................................ ................................................................................................. ............................................................................................2 .......................................2 Future Updates to the WEMG ................................................ ..................................................................................................... ...............................................................5 ..........5

WARSHIPS IN MOD ACQUISITION .................. ........ .................... ................... .................. .................... ...................... ..................... ................. ....... 6 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9

3

Aim.........................................................................................................................................................6 Lines of Development................ Development..................................................................... ....................................................................................................... .......................................................6 .....6 Requirement Management............................................................. Management...... ......................................................................................................... .....................................................10 ...10 Acceptance Management.................................. Management......................................................................................... ..................................................................................13 ...........................13 Information Management................................................................ Management..................................................................................................................... ..................................................... 14 Risk Management.............................................. Management..................................................................................................... ..................................................................................15 ...........................15 Cost and Time ........................................... ................................................................................................ ..........................................................................................16 .....................................16 Through Life Management ..................................................... ............................................................................................................ .............................................................17 ......17 Organisational Structure & Responsibilities .................................................... ........................................................................................18 ....................................18

WARSHIP ENGINEERING MANAGEMENT .................. ......... .................... ..................... ................... .................. .................... .............. ... 22 3.1 3.2 3.3 3.4 3.5

4

Aim.......................................................................................................................................................22 Warship Characteristics............................................. Characteristics.................................................................................................... ..........................................................................22 ...................22 Management of Transversals................................................. Transversals ................................................................................................... .............................................................40 ...........40 Standards ................................................. ......................................................................................................... ...........................................................................................49 ...................................49 Warship Project Activities .................................................. ......................................................................................................... ..................................................................54 ...........54

THE PROGRESSION OF A WARSHIP PROJECT ................... ......... .................... ................... .................. .................... .............. ... 67 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14

Aim.......................................................................................................................................................67 Overview..............................................................................................................................................67 The Design Review ........................................... .................................................................................................. ..................................................................................68 ...........................68 Candidate Selection ...................................................... ............................................................................................................ ......................................................................69 ................69 Option Identification................................................... Identification. ......................................................................................................... ..........................................................................72 ...................72 Design Survey ........................................... ................................................................................................ ..........................................................................................75 .....................................75 Outline Capability Design Assessment .................................................. ............................................................................................... .............................................85 85 System Design................................................... Design.......................................................................................................... ..................................................................................87 ...........................87 Contract Design ......................................... .............................................................................................. ..........................................................................................88 .....................................88 Production Design ............................................. .................................................................................................... ..................................................................................90 ...........................90 Production............................................................................................................................................94 Acceptance ................................................ .................................................................................................. ..........................................................................................95 ........................................95 In-service ........................................... ................................................................................................ ................................................................................................ ...........................................101 101 Assessing warship project project maturity ................................................ ................................................................................................... ................................................... 102

5

ACRONYMS AND GLOSSARY ................... ......... ................... .................. ................... ..................... ...................... ...................... ................... ........ 129

6

REFERENCES & BIBLIOGRAPHY.......... BIBLIOGRAPHY.................... .................... ................... .................. ................... ..................... .................... .............. ..... 133 6.1 6.2

References ................................................ .................................................................................................. ........................................................................................133 ......................................133 Bibliography.......................................................................................................................................133

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MAP 01-020 Warship Engineering Management Guide Introduction

1

Chapter 1

INTRODUCTION

1.1

AIM

1

The Warship Engineering Management Guide (WEMG) gives guidance on the warship engineering process from concept to in-service, including requirements setting, design, manufacture and acceptance by MoD from industry. The WEMG complements complements other naval technical publications including those that are s ponsored by the MoD.

2

The WEMG promotes the coherent development of warship characteristics, which are the highlevel capability-based requirements and acceptance criteria that describe warship capability.

3

It gives guidance on design activities, covering the various stages of acquisition and describes the roles and responsibilities of industry and MoD specialists in warship engineering (see Chapter 4). Furthermore, the WEMG is written to guide in the assessment assessment of the level level of engineering progress of a warship project.

4

The WEMG allows for flexibility in the contractual boundary between MoD and industry by referring to generic roles. These roles, and their their relationships, are shown shown in Figure 1.2. This approach allows a description, within the WEMG, of the activities involved in warship acquisition without assuming a particular commercial model, be this a ‘contract a capability’ or a classic ‘design and build’ build’ arrangement. As a variation, the MoD is beginning to create ‘alliances’ between the MoD MoD and industry that that provide for greater greater risk share. share. The suitability of each each arrangement is beyond the scope of the WEMG.

1.2

SCOPE

1

The WEMG does not intend to be the expert reference on warship engineering. It is intended to provide broad guidance and, where appropriate, highlight other expert areas where additional guidance can be found.

2

The WEMG addresses engineering management - the art and science of planning, organizing, allocating resources, directing and controlling activities relevant to warship engineering. Elements of programme (or project) management (e.g. cost, schedule) will be addressed, but only with respect to how these elements constrain the engineering process.

3

The WEMG is applicable to all surface “warships” and this term is used to include not only those with a clear military capability (frigates, destroyers, carriers) but also auxiliaries and support ships. Additionally, detailed guidance guidance on combat combat systems engineering management management is not covered; the subject will be limited to those aspects, including the combat system, that impact on the whole warship design process.

4

The use of software tools to aid warship engineering management is large and quickly changing. It is beyond the scope of the WEMG to make recommendations about specific tools, although the use of generic tools (e.g. spreadsheets, simple numeric synthesis and analysis programmes, spatial synthesis programmes) is covered where appropriate.

5

Finally, the WEMG discusses the business processes of the MoD in general terms rather than the specific. For example, the Combined Combined Operational Effectiveness and Investment Investment Appraisal (COEIA) will not be discussed in detail as this is covered in other guidance publications, but how to achieve cost effective solutions to meet customer needs will be discussed.

1.3

DOCUMENT STRUCTURE

1

It is the intention of the WEMG that it should be accessible by all personnel involved in warship engineering, and not just by engineering engineering technical specialists. specialists. It is not expected expected that non technical personnel read read the entire document. Instead, the WEMG should should be read to a point point where explanation of the guidance is needed.

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MAP 01-020 Warship Engineering Management Guide Introduction 2

There are four chapters: •

•

•

•

3

Chapter 1

Chapter 1 provides an introduction to the WEMG, as a document, identifying its objectives, scope and background. Chapter 2 sets the acquisition of a warship in the context of wider MoD acquisition policies and processes. There are a number of activities that are generic and applicable to all MoD equipment acquired for use by the armed forces. These include the various boundaries that affect or are affected by the equipment (lines of development), requirements management, acceptance, knowledge management, risk and learning from experience. Furthermore, the organisations within the MoD that have an interest in the equipment, termed “stakeholders”, are also described. Chapter 3 describes the activities, which are used in warship engineering (within the constraints listed in Chapter 2). Chapter 4 relates the processes described in Chapter 3 of the Engineering Management Lifecycle.

The relationship between Chapters 3 and 4 is shown in Figure 1.1. Chapter 4 Progression of a Warship Project Concept… …Design… Concept… …Design… …Production… …In-service …In-service

t n e m e Warship Warship Characteristics Characteristics g a n a M g n i r Transversals e e n i g n E p i h Standards s r a W 3 r e t p a Management Activities h C

Figure 1.1 - Warship Engineering Management Guide (WEMG) Structure 1.4

KEY CONCEPTS

1.4.1

The V-Diagram

1

Figure 1.2 uses the ‘V’ diagram to represent how, with time, the engineering processes are broken down into lower levels of design detail until a point is reached where manufacture and assembly can begin. The process continues through integration, trials and testing until finally capability can be demonstrated.

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Chapter 1

TIME AGENCIES

User (eg Cust 1) (egCust1)

Define capability

Assured capability URD

Procurement Authority (eg DPA) (egDPA)

Accept into service

Define performance and architecture

Management Management of acceptance acceptance

Final trials

SRD System Designer Designer (eg PCO)

Accept off contract

Design system against performance

Production

Design for production

Sub-systems

Equipment supplier supplier

Test and Acceptance Plan lan

Test Test forms fo

Module construction

Assembly sembly

Sub-system design

Installation

SATS

Inspection and HATS

Setting to work and test

Equipment manufacture under quality oversight

Figure 1.2 - The Warship V-Diagram – Agencies and Boundaries 1

2

The left-hand side of Figure 1.2 identifies the agencies involved in procurement .

3

What is important in the application of the V diagram is to recognise that contractual boundaries, internal or external, exist. To ensure that the user gets what he expects, each contractual boundary must have a clear statement of need, requirements, expected deliverable(s) and how the compliance of the deliverable(s) will be demonstrated.

1.4.2

Constraints

1

Warship engineering does not exist in isolation; there are many external influences (or constraints) that directly influence the warship engineering activities that should not be ignored. Depictions of these constraints and how they are perceived to influence the warship engineering process are given in Figure 1.3 and Table 1.1. Chapter 2 puts these in context by relating them to some of these wider constraints.

2

Constraints need to be recognised and understood so that the appropriate trade offs can be conducted.

1 The WEMG does not assign a role to a MoD Integrated Project Team (IPT) or an Industry Prime Contract Organisation (PCO) because the contractual boundaries between these two organisations may change to suit circumstances. Instead the WEMG will discuss the roles of these agencies.

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Chapter 1

INITIAL REQUIREMENTS OR PREVIOUS DESIGN STAGE

REQUIREMENTS

LENGTH

(eg SPEED,PAYLOAD, STANDARDS)

BEAM DEPTH DRAUGHT

SELECT

COST POSSIBLY INCLUDING LIFE STRUCTURE CYCLE COST LONGITUDINAL BALANCE

EMPERICAL FORMULAE

CONSTRAINTS DIRECTLY ON THE DESIGN

FORM SELECT LIKELY MACHINERY

INITIAL CHECKS

SEAKEEPING MANOEUVRING

CONSTRAINTS ON THE DESIGN PROCESS

POWER

CALCULATIONS

SELECT BROAD COEFFICIENTS

ENDURANCE

CONSTRAINTS ORIGINATING FROM THE DESIGN ENVIRONMENT

UPPER DECK MAJOR SPACES

BASED ON TYPE OF SHIP

AREAS

TO NEXT PHASE DESIGN AFTER APPROVAL PROCEDURE

OVERALL PICTURE THE DESIGN SPIRALS DOWN THE SURAFCE OF MODE L

BASED ON TYPE OF SHIP

WEIGHT

AREA / WT BALANCE

GENERAL LAYOUT

DISPLACEMENT

SECTION THROUGH MODEL SHOWING TYPICAL STEPS IN SPIRAL

Figure 1.3 - Warship Engineering process showing influence of Constraints Design Constraints on the Design

Constraints on the Design Process

•

Minimise building time

•

•

Consider foreign sales potential

•

•

Reduce manpower on the ship

•

•

•

•

•

Reduce specialised manpower on the ship Minimise the maintenance load required at the ship Simplify production process in the shipyard Fit up-to-date equipment which is being concurrently developed with the ship

•

•

•

•

•

Minimise time in refit

•

•

Minimise time in port

•

•

•

Comply with international rules existing or likely to come into force Minimise training load to operate ship

•

•

•

Structure of the design organisation Relationship of designer with customer Attitude of design organisation to the latest design techniques Past design type ship data available Countries of origin of designer or design methods The need or ability to buy-in talent to the design team Specialisation and training of the design team State of the art in various fields

Constraints Originating from The Design Environment •

Physical and natural environment

•

Political climate

•

•

•

•

•

•

The exact manner in which money is funded The need to comply with new laws (eg health and safety during build) The political necessity to support ailing shipyards The strategic and political necessity to spread work around shipyards The decision to reduce direct government research Collaboration with NATO allies on equipment

Computer facilities directly on tap and their limitations Quality of general engineering data directly available Research facilities directly under designers’ control The idiosyncrasies, prejudices, rivalries, personalities of the design team

Note: The above examples are not comprehensive. They serve to illustrate the difference in the three categories of “constraints”.

Table 1.1 Constraints in Ship Design – some typical examples

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Chapter 1

1.4.3

Warship Acquisition and Systems Engineering

1

Systems engineering is a generalised model and framework for managing an engineering process. Therefore, it is self-evident that marine products have always been designed and produced using a form of “systems engineering”, even if those particular words were rarely used. It is also true that much of naval architecture and marine engineering concerned with design management is undoubtedly an example of systems engineering.

2

The positive aspects of systems engineering with respect to warship acquisition are considered to be: •

•

•

•

3

Placing the focus on engineering as t he creative heart of the management of projects; Encouraging “joined-up” engineering, although this also needs to be followed-up by the development of a greater variety of practical tools suitable for real situations, products and technologies; A disciplined approach towards software/computer systems as marine products become more influenced by such systems; Encouraging careful planning of the testing and integration process, including the need to trace requirements through the design process to acceptance.

However, a few words of caution are offered in the following areas: •

•

•

The traditional language of systems engineering is heavily software based. Thus, engineers who are involved in the “engineering of systems” need to understand the background to “systems engineering” and only incorporate appropriate practice into their own specialisation; Systems engineering is no magic panacea. For example, the over elaboration of requirements in computer databases, under the banner of “requirements engineering”, without progressive design modelling to establish feasibility in terms of cost and inservice date; Whilst the concept of applying systems engineering methods and techniques to different product areas is valuable, systems engineering cannot be taught or applied in isolation from domain knowledge or experience.

1.5

FUTURE UPDATES TO THE WEMG

1

It is the role of the Naval Technical Publications Policy Committee (NTP PC) to be a joint forum to guide the development and use of Naval Technical Publications in support of warships from concept to disposal. The NTP PC is a DPA/DLO Joint Committee responsible to the DPA XB and the DLO MLPB for ensuring that Naval Technical Publications support the aims of Smart Acquisition.

2

Under the authority of the NTP PC, the Sea Systems Group - Surface Ship division will maintain this document, collating feedback from readers and updating it when appropriate. As such, comments on the WEMG should be sent to [email protected].

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MAP 01-020 Warship Engineering Management Guide Warships in MoD Acquisition

2

Chapter 2

WARSHIPS IN MOD ACQUISITION

2.1

AIM

1

This Chapter sets the acquisition of a warship in the context of wider MoD acquisition policies 2 and processes . There are a number of activities that are generic and applicable to all MoD equipment. These include the various boundaries that affect or are affected by the equipment (Lines of Development), requirements management, acceptance, knowledge management, risk and learning from experience. Furthermore, the organisations within the MoD that have an interest in the equipment, termed “ stakeholders”, are also described.

2.2

LINES OF DEVELOPMENT

2.2.1

Introduction

1

Smart Acquisition is the principle framework within which warship engineering is conducted. The warship is only one part of the system which is required to provide a military capability.

2

There are 8Lines of Development (LoDs) that together deliver capability; these are sometimes referred to as the Eight Pillars of Military Capability or Other Elements of Military Capability (OEMC) and these are shown in Figure 2.1.

Interoperability Organisation

Logistics

Concept & Doctrine

Military Capability

Training

Equipment

Personnel

Information

Infastructure

Interoperability Figure 2.1 - The Lines of Development (LoDs) necessary to deliver Military Capability 3

It is important for warship engineering management is that there is consistency as to what constitutes each LoD, and how each contributes to the overall capability need.

4

Knowing the LoDs, and who is responsible for their delivery, is key to supporting an integrated cost effective military capability. It should also be noted that full capability may not be achieved at a single event, such as In-Service Date (ISD), and may be planned to be a staged or incremental process (see Section 2.4).

2

Chapters 3 and 4 then go into the more specific detail relating to warships.

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Chapter 2

5

Therefore, warship acquisition can be seen to require a wider vision and appreciation beyond just the warship itself. This necessitates identification and interaction with a wide range of project stakeholders, both in the MoD and industry. Maintaining these relationships is a key activity in the acquisition of a warship. In the following paragraphs each of the LoDs is developed under the official MoD definition.

2.2.2

Concepts of Operations & Doctrine A Concept is an expression of the capabilities that are likely to be used to accomplish an activity in the future. Doctrine is an expression of the principles by which military forces guide their actions and is a codification of how activity is conducted today. It is authoritative, but requires judgement in application.

1

Concepts and Doctrine is normally loosely referred to in warship engineering as ‘CONOPS’, however, there needs to be a distinction made between: •

•

•

Concept of Use (CONUSE) - how Equipment & Technology is operated (i.e. relating to SRD boundary); Concept of Employment (CONEMP) - how the Capability is deployed (i.e. relating to URD boundary); Concept of Operations (CONOPS) - how a force is deployed (e.g. Carrier Strike).

2

The distinction is important because there is a need to place requirements in ‘context’ in order to aid their understanding and to support the scrutiny process. This ‘context’ complements the detailed requirement and should not provide unnecessary, and potentially contradictory, duplication to the requirement.

3

The Concepts and Doctrine LoD illustrates the user’s intention of how the capability will be employed once in-service. For the MoD, this LoD will be derived through an iteration process; each stage increasing the definition. The CONEMP will evolve into a CONUSE. As a warship approaches its Acceptance into Service, the CONUSE will usually identify limitations in Doctrine and Tactics, Techniques and Procedures (TTP). These shortcomings will be addressed before at Acceptance into Service.

4

However, a warship is inherently adaptable, so making the production of a single, specific CONUSE unlikely. Adjustments will be made as to how the warship is operated using adaptability in order to increase operational effectiveness.

2.2.3

Training The provision of the means to practise, develop and validate, within constraints, the practical application of a common military doctrine to deliver a military capability.

1

For a warship it may be better to consider the Training LoD as ‘Collective Training’, which is defined as ‘…training which is aimed at improving the ability of teams, units, or formations, to function as a cohesive entity and so enhance Operational Capability.' (Director General Training and Education’s Glossary of Defence Training Terminology).

2

This LoD covers all aspects of training conducted both ashore and afloat. Decisions on equipment design and selection should take into account training requirements (on board and ashore).

3

The training needs of the warship should be assessed throughout the design process in order to maintain a focus on minimising through-life costs.

2.2.4

Equipment The provision of military platforms, systems and weapons, expendable and non-expendable (including updates to legacy systems), needed to outfit/equip an individual, group or organisation.

1

This is the most familiar LoD in warship engineering; it is the ‘Warship’, the extent of which is defined by the SRD boundary. It is reiterated that equipment alone does not deliver military capability. To deliver the capability required by the URD, all LoDs need to be considered.

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MAP 01-020 Warship Engineering Management Guide Warships in MoD Acquisition 2.2.5

Chapter 2

Infrastructure The acquisition, development, management and disposal of all fixed, permanent buildings and structures, land, utilities and facility management services (both Hard & Soft facility management (FM)) in support of Defence capabilities. It includes estate development and structures that support military and civilian personnel.

1

This includes all the facilities required to support the warship through all its life phases, without which it would be quickly become ineffective.

2

Examples are: •

Ship repair facilities, ship building industry and facilities;

•

Graving docks, ship lifts, floating docks;

•

Weapons supplies;

•

Material suppliers;

•

Electronic supplies;

•

Post facilities and craneage;

•

Stores.

3

Most of these are beyond the influence of the designs and often serve as constraints unless there is a (political) will to redress the situation.

4

The infrastructure elements required for the support of the warship should be identified early. This will enable other specialists to develop and maintain the facilities.

5

Note that the adoption of digital systems, computer networks, etc., necessitates new forms of infrastructure.

2.2.6

Information The provision of a coherent development of data, information and knowledge requirements for capabilities and all processes designed to gather and handle data, information and knowledge. Data is defined as raw facts, without inherent meaning, used by humans and systems. Information is defined as data placed in context. Knowledge is Information applied to a particular situation.

1

The preferred method of storage of information and data is tending towards digital means and it is important that it can be easil y accessed.

2

Implicit is the need for strict management and access to the data and its configuration over its lifespan of more than 50 years.

3

This involves the configuration of: •

The storage system i.e. CD, DVD etc.;

•

The file types used, the software and operating systems;

•

The data and information including: •

The translation of data and information for its working format to storage format; Verification and validation of the t ranslated data;

•

The documentation of the stored data.

•

2.2.7

Personnel The timely provision of sufficient, capable and motivated personnel to deliver D efence outputs, both now and in the future.

1

Along with the Equipment LoD, the Personnel LoD is a major through-life cost driver. This LoD includes the provision of manpower, the supply of the i ndividual training solution and acceptability of the personnel solution.

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Chapter 2

2

Manpower includes all MoD personnel (military and non-military) as well as the embarked contractors required to operate, maintain and support the warship during both the entry into service and in-service phases. Training includes both First Of Class (FOC) and in-service training needs, encompassing the provision of training systems and course delivery, in order to develop Training/Operational Performance Statements.

3

Equipment design and selection decisions influence the complement required for both operation and maintenance. An example of this would be the level of automation of a stores system. A fully automated system that required no manual loading would require maintainers with a higher level of training and few handlers to load pallets (for example). A manual system would require fewer, less qualified maintainers but more handlers.

4

Both solutions offer similar performance but different non-technical merits. The automatic system would have a higher initial cost with a lower operating cost (as well as lower complement numbers to be accommodated). It should be noted that a warship is a ‘system of systems’ and that automatic systems tend to be inflexible. It may be that pallet handlers are preferable since they can also be used in other warship operations.

2.2.8

Logistics The science of planning and carrying out t he operational movement and maintenance of forces. In its most comprehensive sense, it relates to the aspects of military operations which deal with; the design and development, acquisition, storage, transport, distribution, maintenance, evacuation and disposition of materiel; the tr ansport of personnel; the acquisition, construction, maintenance, operation, and disposition of facilities; the acquisition or furnishing of services, medical and health service support.

1

The facilities must be available to provide the appropriate material whenever and wherever it is needed.

2

The aim is to optimise the whole life cost by careful management of the support systems through encouraging designs for supportability and the determination of support requirements. The goals are:

3

•

To influence the design with regard to whole life cost;

•

Identify and develop support requirements;

•

Acquire support resources;

•

Provide in-service support.

The majority of the life cycle costs, whilst not incurred are committed during the early stages of the design development. Note that disposal is becoming a more importable issue.

2.2.9

Organisation Relates to the operational and non-operational organisational relationships of people. I t typically includes military force structures, MOD civilian organisational structures and Defence contractors providing support.

1

This relates to how the various groups of specialists are organised such that the appropriate expertise is available in a timely manner.

2

The performance of a warship is dependent not only upon its physical characteristics, the support structure and personnel but also on how they are organised.

3

This is in the form of command structure, and hierarchy, and it works with training to improve the efficiency and effectiveness of the team as a whole. This applies both to military and civilian establishments.

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2.2.10

Interoperability

1

In addition to the DLODs, Interoperability is included as an overarching theme that must be considered when any DLOD is being addressed: The ability of UK Forces and, when appropriate, forces of partner and other nations to train, exercise and operate effectively together in the execution of assigned missions and tasks. In the context of DLODs, Interoperability also covers interaction between Services, UK Defence capabilities, Other Government Departments and the civil aspects of interoperability, including compatibility with Civil Regulations. Interoperability is used in the literal sense and is not a compromise lying somewhere between integration and deconfliction.

2

Each of the discrete LODs is an optimised system; however, it is important that the system of systems which integrates them is also optimised. Similarly interoperability extends this system of systems to cover interaction between the discrete LODs of the other services and establishments.

2.3

REQUIREMENT MANAGEMENT

2.3.1

Introduction

1

A guiding principle in procurement is the development and specification of smart requirements, which is a structured approach to setting goal-based requirements and acceptance criteria. It aims to put the responsibility for specifying requirements with the organisation best placed for the task.

2

The setting of requirements is achieved by the application of the framework for Naval Ship Specifications, Standards and Assurance (see figure), which comprises the General Naval Specification (that is a template for requirements that draws on Maritime Platform Characteristics owned by DEC) linked to key Naval Standards (capturing MoD corporate knowledge and adapted to fit into this framework), a Naval Ship Code (for safety) and Naval Classification (in lieu of Merchant Classification); all linking as a coherent set.

2.3.2

Traditional Approach

1

Historically the MoD has managed requirements by sponsoring a large portfolio of Naval Engineering Standards (NESs), approximately 700, underpinned by operating experience and additional research and development work. These were then called up in ship specifications which were typically developed as an evolution from a previous and appropriate ship specification.

2

These NESs were applied to the ship design and equipment selection. Assurance of compliance was provided through ship approval, inspection activities etc. by MoD organisations.

3

The subject matter of the NESs was wide ranging. However, with reduced resources the MoD struggled to maintain even those standards which addressed essential features and practices unique to the MoD. From the year 2000 onwards NESs have been replaced (renamed in the majority of cases) by Defence Standards (DefStans) these too have been maintained in the most part, however as for NESs the validity of many DefStans has come into questions as technology/RN good practice moves forward and resource within the MoD to update the standards remain scarce. The approach in the future is to maintain a number of key DefStans (in doing so, changing their thrust from a solution to a functional base document) and to retain the remainder DefStans as reference documents only.

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2.3.3

Current/Future Approach

1

As previously discussed the approach to future surface ship requirements setting will be centred on the tailoring of the General Naval Specification. The tailoring process starts with the GNS Part 1 template (Doors® Based, with an exported EXCEL version available), sponsored by TES-SSG. Part 1 being a representative of a combined URD and SRD requirements set, this being divided in to seven main headings:

2

•

•

Role;

•

Interoperability;

•

Operability;

•

Mobility;

•

Habitability;

•

Supportability;

•

Survivability;

•

Adaptability;

•

Safety & Environmental Protection;

•

Constraints.

Initially DEC will take the GNS template, populate and modify as necessary to allow their requirements to be clearly, and in a standard format, populated in the Part 1 at a high level. This will then be passed to the ship IPT who will continue tailor and populate the further detail below DEC’s requirements. It should be reiterated at this point that future ship procurement will be undertaken using Classification Rules (either Merchant Ship or Naval) for all vessel sizes. In additional the Naval Ship Code (naval SOLAS equivalent) provides, in conjunction the principles of JSP430, the backbone of the safety element. A greater use of national and international standards combined with tailored key Naval Standards (DefStans etc.) provides industry the flexibility to deliver a timel y cost effective solution. Moving forward in the design process the GNS comes in to play again in the form of GNS Part 2 Specifications. Again a set of GNS specifications (Part 2) are used in the development of the ship specific specifications, these interface with the tailored Part 1, Classification Rules, Naval Ship Code, JSP 430 and key Naval Standards (Key DefStans, JSPs etc.). Part 2 is broken-down in to a number of discrete technical subjects areas defined by the Product Breakdown Structure (PBS), at a higher level the specifications are grouped as follows: •

Ship Design and Layout (000 series)

•

Platform (100 series)

•

Propulsion (200 series)

•

Electrical (300 series)

•

Combat, Command & Control Systems (400 series)

•

Auxiliary (500 Series)

Figure 2.2 shows the relationship between the elements of the Naval Ship Specification framework.

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Figure 2.2 - Ship Specification Generation 3

A number of useful documents have been developed which assist the authors in the development of a tailored GNS, these are: •

•

General Naval Specification - Guide to the Tailoring Process - Provides some useful hints and tips; GNS Product Breakdown Structure General Naval specification - this document relates to the ship specification breakdown, for example, 301 - Power Distribution Equipment.

Naval Ship Rules 4

The Rules and Regulations for the Classification of Naval Ships are rules developed by an independent organisation for the assessment of the essential features of naval ships. When that assessment is undertaken by Lloyd’s Register and a ship is found to comply with them, the ship is eligible for classification. Naval Ship Code

5

The Merchant Class exists within the framework of international legislation overseen by IMO, a key part being SOLAS. However, IMO SOLAS is unattractive for many naval ships because the military role demands design and operating solutions that are not all compatible with some provisions of SOLAS (i.e. Safety of Life at Sea vs Float, Fight, Move). Disengaging naval ships from conventions such as IMO SOLAS in order to create Naval Class leaves Naval Class in a void which can leave Naval Authorities, Statutory Authorities and Classification Societies confused and result in misinterpretation, or at worst, failure to achieve acceptable levels of safety.

6

This void is filled by the “Naval Ship Code”, funded jointly by Navies, which delivers the following: •

•

•

•

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Safety assurance - Demonstrable evidence that naval ships have been bench-marked against statute, a sound foundation for a robust safety framework and a legitimacy based on the large number of participants (NATO, PfP and NSCA). Capability - Protection of military capability, common standards for interoperability, and enabling responsible competition between Classification Societies under the umbrella of an intergovernmental naval body (NATO). Forum - A framework for Navies and Classification Societies to share ideas and experiences, and reach a common understanding and a world body of knowledge to protect and sustain naval capability. In summary the Naval Ship Code provides a framework for a naval surface ship safety management system based on and benchmarked against IMO conventions and resolutions.

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Key Naval Standards 7

There remains a number of very naval standards required for the warship role. These include subject such as

2.4

ACCEPTANCE MANAGEMENT

1

Acceptance is a process to confirm that a user’s need for military capability (MC) has been met by the system supplied.

2

It cannot be over-emphasised that acceptance is not something to think about ‘later’; acceptance management is as important as requirement management in the early stages of a project when the SRD is being created. Therefore, it requires an indicative design to articulate the acceptance process. This is shown in Figure 2.3 where a list of contract acceptance events is tightly linked to a mature and verifiable SRD within the contract boundary between System Designer and Procurement Authority (i.e. formally agreed). Mature & Verifiable URD

Outline SRD

Reference Design Solution

List of Contract Acceptance Events

Mature & Verifiable SRD Modification controlled by Configuration Management

URD, SRD, Design ‘Trade-Off Triangle’

Integrated, Test, Evaluation and Acceptance Plan (ITEAP)

Other Lines of Development (LODs)

Acceptance in to Service

Acceptance Off Contract

Tests,Trials Inspections

Equipment & Technology LOD Contract Boundary

Mature Design Warshi

Figure 2.3 - Typical Acceptance Process 3

MoD guidance on acceptance management is comprehensive, and a summary of the important concepts for warship engineering is presented in t his Section.

4

ITEA (Integrated Test Evaluation and Acceptance) is used for the totality of the activity, and is focused specifically on ensuring that the MoD actually gets the military capability that it sets out to acquire (see ITEAP in Figure 2.3). ITEA is broadly synonymous with the systems engineering term "Verification and Validation” and includes all the different Lines of Development (LoDs).

5

Verification and Validation are defined as follows: •

•

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Verification (did we build the system right?) is the process of confirming that the characteristics and behaviour of equipment/system comply with the requirements specified in the SRD. Verification provides the information required to correct shortcomings in the equipment/system. Hence it provides the evidence that enables authorisation of Acceptance Off Contract; Validation (did we build the right system?) is the process of generating objective evidence that the MC enabled by the equipment/system satisfies the needs defined in the URD. Hence it provides evidence that enables Acceptance into Service.

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Many well-managed projects address Verification and Validation in carefully controlled steps. This approach may either be progressive up to acceptance of the warship, or incremental following acceptance of the warship as a platform, as defined in the following paragraphs. Progressive Acceptance

7

Progressive Acceptance describes the practice of performing interim activities at key stages throughout the engineering, design, development, manufacture, installation, commissioning and integration of the equipment/system. Its purpose is to minimise the impact of any required remedial action, and to give the MoD confidence in the achievement of performance expectations.

8

This progressive acceptance can be illustrated with an example of a warship’s radar. Initially Factory Acceptance Tests (FATs) would be performed on the radar to determine that it functions in a benign environment with readily available test facilities. Once the manufacturer was satisfied it worked in this environment it would be integrated on to the warship (or a major element of it) and Harbour Acceptance Trials (HATs) would take place. Ideally the HATs would repeat a sub set of the FATs. To test the radar in a way not done before would have the risk of having to remove the radar and return it to the manufacturer’s test facilities for further FATs. The Sea Acceptance Trials (SATs) are a progression from the HATs, in that the ship is being operated at sea whilst the radar is being tested. On completion of the SATs, Acceptance Off Contract can take place. In order to get the Acceptance In To Service the warship would need to be operated with all the other Lines of Development. Incremental Acceptance

9

Incremental Acceptance is formal pre-planned acquisition of capability (URD) or performance (SRD) by stages. For example Incremental Acceptance of a mine-hunting capability could be made by initially accepting first of class, and then having staged deliveries (tranches) that would build up the number of warships to be able to eventually deliver the required capability. This incremental acceptance would also include the other Lines of Development, e.g. recruitment of the necessary personnel, their training (e.g. simulators), having a strategy for their operation, the supplies needed, as well as the shore based personnel and facilities. All these do not need to be in place from day one and can be built up progressively to eventually deliver the required capability.

10

Acceptance may be complicated by an uncertain Design Authority. It is normal that some equipment is provided to the shipyard for installation on the warship by outside agencies arranged by the MoD project, or Duty Holder. The acquisition of this Government Furnished Equipment (GFE) is outside the control of the contractor as the Design Authority who is tasked to provide only ‘Installation Provision made in Design’ (IPMD). An example of this might be the main engines, where the Duty Holder would direct the Design Authority to incorporate the specified equipment in the design and then direct a supplier to provide the equipment (responsibilities are defined in Section 2.9.2). Should there be complications, it is essential that roles and responsibilities are clearly understood.

2.5

INFORMATION MANAGEMENT

1

The following is derived from MoD guidance and identifies a number of fundamental concepts in information management applicable to w arship engineering design management: Configuration management : this defines and controls the configuration items which are defined in terms of requirements documents, designs (and not just drawings and CAD models), contracts and test plans. It is vital that the project has adequate control of its main baselines, while allowing those with authority and need, the means to access and modify the information base in a systematic and controlled manner;

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Traceability : the information base may be highly intricate and inter-related. With traceability in place, the consequences of changes (or deviations from the intended outcome) in one attribute can be checked for their potential impact on others. (Examples may be the traceability between user requirements and elements of the design; applicability of key constraints to certain requirements; links between requirements and tests and those between the management plan or development schedule and the product configuration structure); Information ownership : although free and open access to information is needed, it is important that discipline is exercised in terms of authority to change. For example, customers must own the user requirements even if the IPT is responsible for developing them and prime contractors must have control over the detailed structure of the deliverables. However, once agreed and linked to other information types, neither may make unilateral changes without the agreement of the project as a whole. In all the above cases, information management is an aid to other engineering functions, providing support to the review, change-management and decision-making processes. The overall aim is the efficient use of information by all parties - ‘ write once, use many times ’ is a useful concept. 2

An important system engineering information management effort is the Requirements and Acceptance Database (RADB), which serves to link requirement sets (at different levels) and other elements of data. The linkage is used to ensure the requirement is ‘broken down’ to configuration item level as well as to ensure progressive acceptance can take place.

3

There needs to be a record of design history and design decisions (or Ship’s Cover) for through life support of the project/programme. This will allow assumptions to be revisited at a later time and the validity of decisions to be reviewed.

2.6

RISK MANAGEMENT

1

Risk management serves to reduce the consequences of uncertainty and issues which may jeopardise the project.

2

In doing so, it will identify, analyse and develop mitigation strategies for all issues. This will, no doubt, entail re-planning of the project since items on the critical path have inherent risks.

3

The warship engineer can use his technical knowledge to determine the probability of occurrences; similarly, these occurrences can be further sub-divided as being significant or 3 insignificant .

4

Certain occurrences are events that WILL happen and, as such, they must be accounted for in a project’s baseline Planning & Schedule Management activities; for example of a certain occurrence would be a list of the current legislation that is applicable to the warship. Irrespective of whether the occurrence is considered significant or insignificant it must be addressed. For insignificant certainties it is likely that the only action necessary is to add an entry in an assumptions register to log the fact that it has been taken in to account. However, for significant certainties, management action may be necessary in order to avoid, minimise or absorb the effects.

5

Uncertain occurrences are events that may or may not occur. The type of management action necessary to deal with them depends on their significance. Insignificant uncertainties, which although not warranting specific action, should be addressed within a project’s baseline Planning & Schedule Management activities. An example of an insignificant uncertainty could be the risk of a Commercial Off The Shelf (COTS) pump not being available from a particular supplier. This can be dealt with by identifying other suppliers and the date at which the decision needs to be made for the purchase of the pump.

3

However, these decisions must be regularly revisited in order to assure that they remain relevant.

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6

The term ‘Risk’ is generally used to embrace the possibility of both negative and/or positive consequences. Thus, the same process may be used to manage both risk (more correctly termed threat) and opportunity. An example of an opportunity would be a hull coating material (that is in the development stage) that would increase the life of the hull beyond the performance of the baseline solution. The Risk and Opportunity Management Plan would monitor the availability of the new material, and the hull would be built so it does not preclude its use, and if it can be employed it will be, possibly at no extra cost. If the new material was the baseline, and there were no other alternatives that met the requirement, then the use of the material would be a risk rather than an opportunity.

7

Finally, risks and opportunities associated with other Lines of Development should be considered with a framework to collect these together in a unified manner. These risks/opportunities exist outside the control of w arship engineering and possibly beyond the control of the warship project. For these risks, warship engineering should clearly identify the impact to the warship design and the actions that are necessary to mitigate or utilise them.

2.7

COST AND TIME

2.7.1

Introduction

1

In order to successfully acquire a warship, it will be necessary to pay close attention to cost and time aspects from setting the original budgets through to final acceptance in-service and beyond.

2.7.2

Finance and Resources

1

Although the early stages of a project will be concerned with identifying the budget requirements to bring the project to fruition, certain budget constraints may start to become apparent quite early. These cover primarily the areas of finance and resources.

2

The process with which the URD and any indicative design are balanced (see Section 2.3) is termed Cost Capability Trade Offs (CCTO). In order to get an idea of how much capability is delivered by various solutions and at what cost, indicative designs need to be developed to understand the design drivers and the costs estimated for each warship design option. These CCTOs are used to establish the necessary budget. The number of warship design options to be considered should be as many as you need to determine the design drivers. It should be noted that each warship requirement has these design drivers. They may not be unique, but it is dangerous to assume that the design drivers are the same from warship to warship.

3

However, once these stages are passed and budget targets set, it is certainly advisable that available budget limits are made clear to all parties up front. This will avoid repeated bidding rounds with different scopes of supply.

4

Paradoxically, costs may not be the biggest constraint early on as timescales may be adjusted or other projects displaced to compensate. The industrial resources to design and manufacture a complex warship may be far more of a consideration than in the past. With fewer new classes being procured there has been a substantial reduction in the available resources. It is already apparent that if the national policy is to retain warship production nationally then a coherent approach across projects will be required. If international procurements are undertaken the same issues will apply but on a larger and even more politically complex scale. Resource availability and coordination constraints involve the factors shown in Table 2.1 - . Design capability MoD oversight and review Industry design teams Manufacture Facilities Labour skills Coordination across suppliers Commercial/contractual issues • •

• •

•

Continuity of Resources Relevant experience e.g. staff experienced in frigates cannot easily transfer to submarines and vice versa. Employment e.g. if skills are not exercised they will leave the industry and are unlikely to return. •

•

Table 2.1 - Resource availability and coordination

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2.7.3

Timescale Constraints

1

Timescale constraints can be considered in two areas; existing capability life and technology development needs. With regard to existing capability life, the programme for a project is driven by the desired In-Service Date (ISD). This in turn will be dependent on either the need to provide a particular capability that does not already exist or to replace an existing solution, which is either obsolete or no longer cost effective to maintain in-service.

2

For technology development needs, the project timescale will determine the time available to develop equipment or manufacturing processes to be used in the warship. Technology maturity levels provide an indication of the state of a technology. They do not necessarily imply the time or cost needed to mature that technology to a state at which the risk of inclusion is acceptable. If a technology is considered desirable and would enhance the warship under consideration then inquiries must be made in order to ascertain factors such as required research and development, timescales to bring to production, IPR availability and cost and risks.

2.8

THROUGH LIFE MANAGEMENT

1

Through Life Management serves to maintain the current capability as well as to manage improvements. The Through Life Management Plan (TLMP) encompasses the entire acquisition cycle. It is initiated, developed and maintained by the project team and provides visibility to all stakeholders of the through life management planning process. The TLMP covers the following topics: Obsolescence

2

Obsolescence affects all equipment, software, tools, processes, support products, standards and specifications. It impacts upon all stages of the life of equipment. It is inevitable, may be expensive and cannot be ignored, but its impact and cost can be minimised by forethought and careful planning. Deterioration

3

Deterioration affects the hull, systems and equipment, particularly in old ships. Deterioration may impact on safety and capability and, unless managed and controlled, place operational availability at risk. Incremental Acquisition (IA)

4

Incremental Acquisition (IA) provides for equipment capability to be upgraded in a planned way, from the initial delivery of a specified minimum acceptable performance to eventual achievement of target performance. The warship engineering management should allow for Incremental Acquisition in the context of the IA plan, w hich will take in to account obsolescence issues. Technology Insertion

5

Technology Insertion may occur after In-Service Date (ISD) and should address system obsolescence. It will also be funded at Main Gate and managed through the Whole Life Support Plan. For hardware, this is subject to an announced future end of production date by the manufacturer. Software is subject to an announced future end of support date. Capability Upgrade

6

Capability Upgrade may occur after ISD and is the modification of the system of interest during the operational stages in order to introduce new or enhanced functionality or capability; and/or to improve system reliability; and/or to counter technology obsolescence.

7

The scope for all these approaches is largely due to the ‘systems of systems’ nature of a warship. For Technology Insertion and Capability Upgrades there should be sufficient margin (wild heat, space, etc) within the warship to allow equipment not originally foreseen in the design to be accommodated. Technology management can support Margin Policy and Management by forecasting the performance and demands of future technological developments on the warship as well as estimating the impact of these technologies on overall capability.

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2.9

ORGANISATIONAL STRUCTURE & RESPONSIBILITIES

2.9.1

Introduction

1

Organisational structure and the associated responsibilities can be described in generic terms which relate to the current MoD policy and structure. In all cases, it is essential that the generic roles and responsibilities are captured within the specific arrangements for a project, which may well be based upon the current arrangements under Smart Acquisition.

2.9.2

Generic Roles and Responsibilities

1

The Owner (or Duty Holder) defines the need for the ship, procures it, uses it, and disposes of it and, as such, he is always ultimately responsible for all the implications of its existence. In discharging his duties, the Owner must ensure that a Design Authority (DA) is established and is competent to control the ship design.

2

This Section explains the roles and responsibilities of Owner and the DA sufficiently to enable the implications of holding the DA role within MoD or delegating all, or part of it to industry, to be understood. In addition, some guidance is also provided on equipment sponsors and system and equipment design authorities.

3

The DA can be within MoD or in industry. System and equipment DAs can also be in MoD or industry, but the allocation of responsibilities must always be clear, documented and visible to other DAs and the owners. In general, design responsibility for any given item will only reside in one organisation. In essence, MoD would retain technical responsibilities, which are more appropriate for government.

4

In maintaining control over the design the DA takes holistic responsibility for the design and all consequent decisions. This involves establishing and maintaining the design intent as being the complete configured definition of the design down to component level, including the prescription of operating and maintenance requirements in order to provide agreed levels of material readiness. This role necessitates specifying the material to be provided by the supply chain, covering manufacturers and suppliers of equipment. Duty Holder Responsibilities

5

The DH is responsible for managing the balance between capability and cost. These decisions are driven by the debate of operational and technical imperatives between the DH and the customer.

6

In reaching decisions the DH will seek appropriate advice from the DA and takes full responsibility for the consequences of departing from that advice. Regardless of the DH’s decisions, the DA remains responsible for the accuracy of the advice it gives. As such, the DH is to: •

•

•

•

•

•

WEMG Issue 01

Take ownership of ship design, including performance requirements and maintaining the Systems Requirement Document and specification and provision of GFE; Take ownership of ship safety case including maintenance of certification and classification, specification of design codes and practice and ultimately, approval to operate; Define the correct apportionment of responsibility/liability/incentive in the Terms of Reference of all suppliers including the DA, where it is a part of MoD, or the contract, where it is delegated to industry; Ensure a DA organisation is established and monitored such that the configured design envelope is maintained throughout the life of the ship. This includes the correct specification and maintenance of organisational interfaces and constraints; Satisfy regulators and legislative bodies that the ship is operated within the design envelope set by the DA or that there is appropriate justification where departures from the design envelope are necessary; Manage the integration with relevant Lines of Development;

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MAP 01-020 Warship Engineering Management Guide Warships in MoD Acquisition •

•

•

•

Chapter 2

Ensure the contractual arrangements used to employ any Design Authority include an exit strategy, which ensures continued support to the Operating Authority, should the operation of the DA fail. There should be no impact on the Operating Authority if DA is moved between organisations; Monitor the material state, ensuring the ship is adequately maintained and maintaining operating and maintenance records from which the DA can confirm the ship has been operated within the prescribed envelope, and agreeing the recovery action and commercial consequences with the DA when it has not; Monitor the performance of suppliers, including any DA and taking corrective action when necessary; Communicate operating and maintenance procedures that maintain design intent to the operator.

Design Authority Responsibilities 7

The DA is responsible for developing and maintaining the ship design that satisfies the DH’s requirement, specifies the design in sufficient detail for it t o be built and maintained, considers the implications of departures from the specification, records the material state and provides instructions for the operation of the ship.

8

These activities are carried out in a coherent way so that the DA can provide assurance that the ship will meet the DH’s requirements providing it is operated in accordance with the instructions provided. As such, the DA is to: •

•

•

•

•

•

•

Develop and maintain the overall design of the ship including ownership of system and equipment performance requirements and overall integration of the design, and for ensuring that the design meets the design intent defined by the DH and provides an adequate level of safety to the personnel on board, third parties and the environment; Take ownership of risk that the ship meets the performance requirements and is safe if operated and maintained within defined operating constraints; Provide configuration management of the design including the identification and maintenance of an audit trail for ship design standards, codes and regulations (see Table 2.2); Accept the obligation to supply sufficient information to enable safety regulators to fully assess the features of the design and for the DH to take ownership of overall ship safety; Prepare reliable information relating to the operation and maintenance of the ships and provide this via the DH to the operating and maintenance authorities; Identify and task Technical Authorities to support the DA for specific systems and equipment; Ensure that it has sufficient resources and competence to maintain and update the design, complete necessary analysis and implement design changes as required and to report shortfalls in resource and/or competence to the Duty Holder.

Technical Authorities Responsibilities 9

Each TA is responsible for developing and maintaining the design of his system and/or equipment within the overall design of the ship. As such, each TA is to:

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MAP 01-020 Warship Engineering Management Guide Warships in MoD Acquisition •

•

•

•

•

•

•

Chapter 2

Own the system and/or equipment design; Own the system and/or equipment safety case and production of information for use by the DA in support of the ship safety case; Develop and maintain the system and/or equipment design, seeking sufficient information from the DA as necessary to support integration into the ship and meet DA requirements; Identify and maintain an audit trail for system and/or equipment design; Take ownership of the risk that the system and/or equipment is fit for purpose and safe if operated and maintained within defined limits; Define and maintain system and/or equipment operation, maintenance and support documentation that when applied will maintain the design intent; Ensure that it has sufficient resources and competence to maintain and update the design, complete necessary analysis and implement design changes as required and to report shortfalls in resource and/or competence to the DA;

•

Approve modifications and changes to operating envelopes;

•

Maintain reference and support documentation and specify production standards.

Document Description System Requirements Document Captures the ship performance requirements Defect Register Captures safety and performance shortfalls Safety Case Portfolio of evidence to justify safety Certification Current MoD, statutory and classification Emergency Preparedness Salvage pack and associated procedures Maintenance Management System Defines maintenance requirements Support Solution Architecture and contracts for support Design Information relating to the design is to include, but not limited to: i. Safety Management Plan; ix. System and equipment specifications; ii. Book of Calculations; x. Ranging reports - IR/Radar/Noise; iii. Tank Calibration Book; iv. Stability Model; v. Stability Model Validation Report;

xi. Aviation Interface Safety Case; xii. Master Equipment List; xiii. WBS;

vi. Stability Information Book and/or Loading Manual; vii. Ships Drawings - Level 1, 2 and 3;

xiv. PBS; xv. Budgets for weight, port, margins;

viii. 3D CAD model;

xvi. Ships boats safety case; xvii.Lifting equipment safety case.

Table 2.2 - Key Information to be maintained by the Design Authority 2.9.3

Organisations in Acquisition

1

Acquisition is built on the integration of relationships between customers and suppliers. Characteristics of an acquisition approach are clearly identified customers and the formation of Integrated Project Teams (IPT’s) to supply the requirement. There are a number of organisations involved over the lifetime of the project as detailed in the following paragraphs. Requirements Staff

2

Requirements Staff have responsibility for identifying the capability required to meet the UK’s Defence objectives, for translating those requirements into an approved programme and for ensuring effective delivery of that new capability into service.

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Chapter 2

Operating Authority 3

Operating Authorities have the responsibility for operating the capability as a defence capability that incorporates all Lines of Development. Operating Authorities manage the equipment inservice and provides relevant advice and expertise to support the Requirements Staff in optimising future capability. Integrated Project Team

4

The Integrated Project Team (IPT) is charged with acquiring the equipment and technology required to deliver the capability defined by the Requirements Staff within the allocated resources and taking into account the wider requirements of other stakeholders. As the Duty Holder, the IPT is responsible for ensuring that the equipment and technology delivered provides an adequate level of safety. The IPT will engage industry to provide the equipment and technology. In doing so, the IPT will depend on industry to support the Duty Holder role to an extent that is appropriate to the project. Once a ship is in-service, the IPT is charged with ensuring that the ship is capable and available during its scheduled operation. The IPT will co-ordinate other MOD stakeholders industry to ensure availability. Naval Authorities

5

Naval Authorities regulate hazard areas to provide independent safety assurance (reporting to the Ship Safety Board) that, when applied effectively by both the Naval Authority and the Duty Holder will reduce project risk and improve safety and capability. The Naval Authorities require assurance that the ship material state is consistent with the design and agreed standards and acceptance criteria. To achieve this, the Naval Authority may either attend a ship or by represented by a Recognised Organisation who is formally authorised by the Naval Authority to act on their behalf (representation is arranged by the Integrated Project Team). Recognised Organisations

6

Organisations formally authorised to act on behalf of a Naval Authority to provide assurance that the ship material state is consistent with the design and the agreed standards and acceptance criteria in order to support Naval Authority certification. Subject Matter Experts

7

Subject Matter Experts (SMEs) within the MoD provide advice on how certain specialist aspects of warship design, construction and operation should be addressed. IPTs are encouraged to take into account the advice of SMEs wherever possible in order to ensure that the equipment is acquired and managed in a cost-effective manner that is consistent with other related MoD projects and equipment. Similarly, SMEs are encouraged to provide pragmatic advice taking into account the constraints placed upon the IPT. Investment Appraisal Board

8

The Investment Appraisal Board (IAB) is responsible for reviewing submissions from the IPT for gate approval and approving the subsequent phase of the project.

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3

Chapter 3

WARSHIP ENGINEERING MANAGEMENT

3.1

AIM

1

The aim of this chapter is to outline the issues and aspects that need to be taken into account throughout the acquisition process from concept to disposal. To set the scene, various “warship characteristics” are described that reflect the nature and role of a warship. A selection of transversal issues are described that cut across the design activities (see Section 3.3) followed by an overview of the management activities required to monitor and control the acquisition of a warship. Finally, it is appropriate to outline the variety of standards that are required to support the successful acquisition of a warship.

3.2

WARSHIP CHARACTERISTICS

3.2.1

Introduction

1

To facilitate the development of the User and System Requirements and Acceptance Criteria for warship projects, a set of generic warship requirements has been developed. These generic requirements are used along with role specific (e.g. combat systems) and warship specific (e.g. landing platform docks, aircraft carriers) requirements to produce the User Requirements Document (URD) and System Requirement Document (SRD). The generic warship requirements have been developed by learning from the experiences of previous projects and through applying best practice identified by these projects. These generic warship requirements are known as Warship Characteristics and are summarised below.

2

Warship characteristics are high-level, capability-based, requirements and acceptance criteria that ensure coherency and affordability across the fleet. They encourage high-level requirements 4 to be cascaded to detailed system and sub-system requirements and acceptance criteria.

3

The warship characteristics either drive or place constraints on the design and are listed below under the following broad headings (in alphabetical order):

4

•

Adaptability;

•

Deployability;

•

Habitability;

•

Interoperability;

•

Maintainability;

•

Mobility;

•

Operability;

•

Producibility;

•

Safety;

•

Supportability;

•

Survivability;

•

Upgradability.

When developing and setting the warship characteristics and the User Requirements it is important to understand how they drive the design and hence cost. The specification of inappropriate or excessive performance requirements can have a significant impact on the design solution, making it unaffordable and, in the extreme, unachievable. Therefore, it is important to understand those performance requirements that have the most significant effect on the design solution, how requirements interact and allow a balanced design solution to be achieved.

4

However, it should be recognised that some requirements are whole ship characteristics that cannot readily be cascaded down to totally define the systems comprising the warship. They may be enhanced to reflect specific roles and warship types.

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5

Performance drivers will have a fundamental impact upon the design of the ship (e.g. the location and size of the flight deck and hangar). An understanding of the generic and role specific design 5 drivers will enable them to be addressed early and given sufficient priority throughout the design process. These can then be monitored and managed through regular meetings such as Design Reviews or safety reviews.

6

Constraints are limitations on what can be produced; they take many forms and must be made clear as early as possible. If they prove to be a major design driver, then the extent of their validity must be investigated and included in the trade-off studies. Examples of when constraints were allowed to jeopardise the solution include: •

•

On LPD(R) the requirement for a Ro-Ro LCU led to wider LCUs. This role specific requirement then drove the well dock dimensions. The generic requirement for damage stability drove the width of the hull in way of the dock. This in turn drove the size of the ship; During the 2nd World War the RAF’s first 4 engine heavy bomber was the Short Stirling. Its wingspan was constrained to allow it to fit in to existing hangars. It was not very successful because of this and was completely eclipsed by the later Halifax and Lancaster, which had much longer wings and new hangars.

3.2.2

Adaptability

1

It is often beneficial to have a design that is adaptable to new roles in-service. However, this flexibility will invariably lead to design compromises and the vessel may ultimately become ineffective in any of the required roles should these design compromises not be managed effectively.

2

Thus the different roles of the vessel must be prioritised such that the designer has a clear understanding of the end user intentions. In turn, it is important that the end user is also made aware of any operating limitations imposed by the warship design style that may limit 6 adaptability . Many design decisions may have been pre-empted by earlier decisions on weapon and equipment options; for example, it is not unusual for machinery options to be prescribed before the start of the ship design, placing limits on performance and constraining the design.

3.2.3

Deployability

1

The environment in which the vessel is expected to operate is one of the most onerous design drivers. Environmental conditions should be defined to take account of the ship’s role and described in terms that drive the design of the ship, systems, equipment, manufacture, installation, tests and trials of individual items of equipment. The environmental requirements may also need to be specially considered for differing parts of the vessel and its systems. Environmental performance drivers include: maximum and minimum values of temperature, humidity, salinity, wind, waves, swell, sea ice and icing, current, w ater depth and visibility.

2

The more extreme the environment in which the ship is expected to operate, the more robust and generally larger the design must be and the greater the propulsion power and electrical power consumption required to operate in those environmental conditions. An example of environmental conditions driving aspects of the design is: •

The sea state operating requirements for HMS Scott required a deep operating draught to minimise ship motions during surveying, however, it needed a shallow draught for entry into port. These requirements then drove the maximum and minimum draught, the ballast tank capacities and ballasting system requirements for the vessel.

3.2.4

Habitability

1

This group of Warship Characteristics covers accommodation, domestic services, recreation, victualling and waste management.

5 6

Developed during early Option Identification and Design Survey activities. For example, using the ship in a sea area and in weather conditions for which it was not designed.

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2

Accommodation, recreation and victualling requirements are currently design drivers. In post World War II years, frigate dimensions tended to be volume constrained, largely due to the increased space devoted to accommodation and to support weapons systems. Recently, however, there have been attempts to reduce warship complements, and modern micro electronics have tended to reduce weapon system space requirements.

3

However, any volume saving achieved may be offset by the future requirements for accommodation standards, onboard storage handling and offloading of waste and equipment removal routes.

4

Accommodation standards ensure that personnel have adequate facilities for sleeping, recreation, messing and washing/toilet, with adequate access and within a controlled environment. In developing the quantity and standard of accommodation due consideration should be given to: •

•

Warship’s operating profile; Provision of suitably high-standard accommodation to aid rest and relaxation and to promote personnel retention;

•

Facilities for mixed-sex crews;

•

Facilities for allowing f or ‘social grouping’ of accommodation areas;

•

Facilities for hierarchical separation requirements;

•

Variable loads on accommodation (i.e. permanent versus temporary embarkees).

5

‘Hotel’ services (catering, hygiene, waste and garbage disposal, fresh water, etc.) appropriate to the number and type of embarked personnel must be provided. Whereas accommodation (spatial and other) is clearly defined in various standards, the designer has scope in locating accommodation spaces. Principal drivers for accommodation space location are environment/ship motions, safety/escape, functional grouping of compartments (e.g. locations of victualling stores, galley and commissariat), access to related spaces, grouping by rank/privacy/gender and vulnerability (especially zoning).

3.2.5

Interoperability

1

Interfaces with other operational systems, vessels, equipment and organisations need to be identified and managed.

2

Where there are links with other operational systems or equipment then all interfaces must be clearly established. These systems or equipment may exist or may themselves be the subject of a procurement programme. If the latter, then it is vital that a means of managing the evolving interface is established early in order that unnecessary burdens are not placed on one project or the other.

3

Interfaces may take many forms such as physical interfaces or envelopes, or sub-system or equipment compatibility (e.g. stores handling systems, fuel, weapon systems/ammunition). Non physical interfaces, involving frequencies, software, etc, involving communications, command and control, require rigorous definition but can be managed, provided all parties to the interface are involved.

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Chapter 3

Ship to Air 4

The requirements for aviation facilities have a major impact on the design of a warship. The type and number of aircraft and unmanned air vehicles (UAVs) that will be operated from the warship drive the size and location of the flight deck, as well as the hangar and other support arrangements. For example, the following characteristics are considered key to successful 7 aviation arrangements for a modern frigate or destroyer : •

•

•

•

•

•

•

5

Adequate operating clearance between hangar and forward spot; The location and configuration of the hangar to ease aircraft handling and minimise air turbulence over the flight deck (normally the hangar is located immediately forward of the flight deck to negate the requirement for a complex aircraft lift); The flight deck should be long enough to avoid the tail hanging over the end of the ship; Positioning and height of the flight deck to minimise impact of ship motions and water on operations; The position of the flight deck should minimise the impact of ship motions on aviation by bringing the spot forward as far as possible, but maximising the separation between spot and superstructure; The hangar should be large enough to undertake the necessary level of onboard maintenance including usually rotor head removal driving hangar deck height; Requirement to operate both manned and un-manned aircraft (UAVs).

Given that aviation plays a key role in a modern warship it is important that the aviation requirements are given the appropriate level of priority and considered from the out set. Ship to Boat

6

The ability to launch and recover Rigid Inflatable Boats (RIBs) or other sea boats in adverse weather conditions is a common requirement. These sea boats can be 6-8 metres in length and up to 3 metres beam with a weight of several tonnes. The storage, handling, launch and recovery of these boats requires special handling equipment, which must be positioned as close to midships as possible to minimise the effects of ship motions. The boats and their handling equipment also take up a large amount of upper deck space. Thus the requirement to launch and recover RIBs or sea boats rapidly (for “Man Overboard”) will be a major design driver for smaller warships.

7

The positioning of the boat launching equipment is also likely to conflict with the optimum Replenishment at Sea facilities, which should also be located close to midships on either side of the vessel. Ship to Ship

8

This includes all requirements for operating with other ships, the principal driver being Replenishment at Sea (RAS). RAS is a whole ship evolution and requires the designer to consider reception areas, breakdown areas and strike down routes. RAS reception points should be located as near to midships as possible on both sides of the vessel to reduce the effect of ship motions. Space must be provided adjacent to the RAS reception point to break down stores into smaller packages which can then be transferred to storerooms. To facilitate RAS operations, storage areas should be as close as practicable to the reception point.

9

Consideration also needs to be given to the arrangements of potential supplying vessels – not only in terms of physical arrangement, but also rig type, nozzles, requirements for back RASing of waste, etc. Consideration should also be given to potential hydrodynamic and dynamic interaction between the warship and the supplying ship.

10

Given that trends are to increase the speed of transfer of bulkier and heavier loads, it is likely that Replenishment at Sea will place more onerous design requirements for future warship designs. In particular, vessel motions and manoeuvring characteristics may come under greater scrutiny.

7

These requirements will be in conflict with other requirements and a compromise will be necessary.

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Chapter 3

Ship to Shore 11

This includes requirements for berthing and docking, but also services, access and security, which may restrict the maximum dimensions of the vessel, as may the availability of dry-docks and repair facilities. The location of the facilities may also impose an air draught limit (for passing under bridges). Any obvious size constraints should be clearly established.

12

Berthing may place similar limitations on the vessel and drive the design of the propulsion and manoeuvring machinery. In addition, sufficient space and equipment must be allowed on the fore deck and the quarterdeck to safely moor the vessel and conduct seamanship evolutions (see Admiralty Manual of Seamanship). Ship to Underwater

13

This involves the requirements for autonomous & towed underwater vehicle launching, recovery and storage arrangements. It includes the requirements for fuel storage and handling, spares and maintenance.

14

These underwater vehicles may be deployed via a moonpool, over the transom or over the side of the vessel. For a warship it is more normal to deploy such equipment over the transom, which can be hazardous due to the exposed location, greater vessel motions and wave action. These factors in turn may drive the aft end structural design and equipment handling arrangements in way of the quarterdeck.

15

For some vessels a moonpool may be considered, as it allows equipment to be deployed in a more controlled manner. Moonpools, by their very nature will be located close to midships to reduce ship motions and water surge. The moonpool, surge chamber, handling space and equipment take up a large amount of space near midships and their effectiveness reduces with forward speed. Thus moonpools should only be considered where deployment of underwater equipment at low speed is a primary requirement of the ships role.

3.2.6

Maintainability

1

Maintainability is the adaptation of the design such that maintenance during the in-service phase of the CADMID cycle is facilitated. It can involve the provisions of maintenance envelopes and access, removal routes, provision of jigs, lifting facilities and test facilit ies etc.

2

A difficulty which could be met is that the beneficiary of this design work ‘resides’ in the future. Should significant investment be required the budget could prove difficult to acquire.

3

An important factor especially when comparing to producibility (which supports the build) is that most work will be carried out on board in an environment resembling that of traditional outfit afloat with consequential inefficiencies.

3.2.7

Mobility

1

The Mobility Warship Characteristics cover endurance, manoeuvring, navigation, seakeeping, seaworthiness and speed. The maximum speed and operating profile of the vessel has a very significant impact on the design of the warship, the Unit Production Cost (UPC) and through life costs of the vessel. Specifying a high value for maximum speed for a large displacement warship drives the designer toward a long slender design, and may encourage alternative hull forms such as catamaran or trimarans. This, along with the mission profile, will then drive the propulsion machinery configuration.

2

The requirements for seakeeping and seaworthiness also drive the design. In general, increasing the displacement and dimensions of the vessel will improve the seakeeping and motion characteristics of the vessel. However, large changes are required for relatively small changes in seakeeping characteristics. Increasing the length of the vessel will reduce pitch and heave motions in head seas and thus increase operational capability in bad weather, however, there will be an increase in relative bow and stern motions. Sufficient beam is required for good stability, but too much will cause rapid rolling and high accelerations, particularly high in the vessel and at the deck edge.

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Chapter 3

3

Increasing the draught can also improve the motion characteristics. Adequate draught is also required to minimise the risk of slamming, air drawing and cavitation in way of the sonar and to prevent cavitation and over-revving of the propulsion motors. Deck wetness is governed by the freeboard and bow flare, and it is necessary to ensure adequate freeboard both at the forward end of the vessel and also in way of the flight deck. However, too much freeboard will make it difficult to launch and recover boats and underwater vehicles and also increases the windage of the vessel driving up the beam.

3.2.8

Operability

1

Warship Operability Characteristics cover the following topics:

2

•

Aesthetics;

•

Arrangement;

•

Ceremonial;

•

C4I;

•

Complement;

•

Functionality;

•

Requirements for medical facilities, offices, workshops and ship security;

•

Operator Interaction;

•

Seamanship;

•

Sensors;

•

Store handling.

C4I requirements for operational spaces, location and spacing of sensors and complement are usually critical design drivers for a surface combatant. Operations Spaces

3

Current practice is to locate the operations spaces in a single complex, possibly over two deck levels. The decision as to where to locate the operations complex is important and has a significant influence on the configuration and layout of the vessel. It should be fully addressed at the outset of the design process with particular reference to vulnerability, using whatever tools are appropriate. For example, at the early stages simple ‘Rules of Thumb’ – separation, concentration, redundancy, etc. may be all that is possible. As the warship definition increases then more sophisticated analysis tools may be brought to bear.

4

Whilst current practice may call for collocation of command functions in a common operations room this is by no means certain for future platforms. Several NATO and allied navies have vessels in build or in-service that use distributed command systems, whilst ships of some other nations have used this style of command system architecture (albeit at low levels of technology) for decades. Distributing the command function through the ship confers significant benefits in terms of improved survivability.

5

There is no one ideal position for a single operations complex and the designer must consider the comparative advantages and disadvantages of each location, and work closely with the User and Procurement Authority to ensure that the design solution reflects current operating policy. The difficulty in finding an ideal location may reinforce the conclusion that local operational control is the sensible way ahead.

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Chapter 3

Possible options for vertical location are: •

•

•

Immediately adjacent to the bridge - Locating the operations complex adjacent to the bridge has significant advantages in small-scale operations, such as fishery protection duties. It is, however, a vulnerable location and has relatively more lateral motion than a lower location and provides little protection from radiation in a nuclear fall-out situation; Deep in the hull - A deep location for the operations complex provides some protection against missile strikes, above-water action damage and fall-out. A separate command shelter station is, therefore, not necessary. On the other hand, a deep location forward of a conventionally located machinery block may have limite d deck space due to the hull lines, and may be severely constrained in length by the position of watertight bulkheads required for subdivision. At such a low level there will be no fore-and-aft access through watertight (WT) bulkheads, access and escape may be less than ideal and there will be little growth potential unless it is designed in from the outset and can also give rise to complex cable routing. Although having more protection from above-water damage, it will be correspondingly more vulnerable to underwater damage unless watertight boundaries internal to the hull (e.g. decks and inner longitudinal bulkheads) and suitable access trunks and service provision are included that allow operations to continue whilst the surrounding spaces are flooded; At mid-level (No. 1 or 2 Deck) - An intermediate position appears to combine most of the advantages of the two extreme locations described, but it must be accepted that it is at the most vulnerable level to sea-skimming missile strikes. It should, however, be above the damage waterline and will be in a readily accessible and spacious part of the ship.

7

In the context of current operating policies whereby it is necessary for the command to have ready access to both bridge and operations room, there is a case for locating the operations room in the same fore and aft part of the ship as the bridge. This will conflict with a requirement to locate them in separate zones, unless the zone boundary is contiguous with both of them, one each being immediately forward and immediately aft of the zone boundary. However, even this arrangement will still give a higher probability of losing both. Alternatively, only the command/Threat Evaluation and Weapons Assignment (TEWA) element may be combined with the bridge.

8

The designer should be aware that the operations complex is likely to require additional deck height to allow for false floors (to accommodate cabling, shock mounting rafts, etc.) and ergonomic (human factors) requirements, such as the requirements for personnel to have clear visibility of bulkhead-mounted displays, etc. It is also a prime area for considering the adoption of space margins, easy upkeep by exchange, and for adaptability.

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Chapter 3

Sensors, Effectors and other Mission System Interaction 9

The optimum positioning of the sensors, effectors and other mission system components and their integration is essential to successfully meet the operational role. The designer must have a 8 clear understanding of, and detailed information , on the following for each prospective weapon and sensor: •

Weight of all components as this drives the structural design and st ability;

•

Space requirements, including location, maintenance envelopes and removal routes;

•

Demands on support services, including power, voltage, frequency, tolerances, etc;

•

Chilled water supply; quality and quantity of waste heat;

•

Physical clearances and location for RADHAZ;

•

Electronic separation for EMC;

•

Delivery time/state of development – this impacts on the design margins that need to be applied;

•

Other special requirements; e.g. length of wave guides, data highway needs;

•

Impact on Combat Management System;

•

Manning requirements;

•

Links to Capability and Interoperability W arship Characteristics;

•

Requirements for magazines, weapons preparation areas and supporting stores and workshops.

10

It greatly increases the risk to the programme to design a ship to carry a major system that does not, at least, exist in prototype. Even then, the wise designer will allow for the growth of items that are not in full production by incorporating judicious design margins. It is also often said that ships should only be designed to accommodate tested and tried weapons, but this seems a certain route to pre-natal obsolescence.

11

The reason for a new warship is often a new weapon or sensor so these risks cannot always be avoided. Indeed the contractor for a major new, concurrently developing, weapon system is invariably unable to provide firm data and, as stated above, judicious design margins should be developed. Complement

12

A significant driver of Through Life Cost (TLC) is complement. The designer, therefore, needs to be particularly careful not to inadvertently introduce features that may increase the complement. Typical examples are inefficient RAS arrangements, stores routes, removal routes, maintenance envelopes, damage control arrangements, accommodation, and poor attention to husbandry.

13

It may be possible to minimise the complement by introducing labour-saving devices and equipment, but the implications on all aspects of the design must be carefully addressed from the outset. It is important to realise that many of the crew are multi-role so eliminating one task may not reduce the crew size. The key ‘complement driver’ tasks include damage control, maintenance, watchkeeping, husbandry and off ship tasking (humanitarian, policing, etc).

3.2.9

Producibility - Design for Production

1

The traditional approach is to design for function on the assumption that anything can be built. This can result in expensive ships.

8

These are all examples of the need for allocated margins, especially for equipment which is not mature.

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Chapter 3

2

An alternative is to include production issues as another trade-off topic. The value of producibility is increased when it is included early in the design process. The principle reason being that the majority of project costs are committed early. Added to this is the huge cost incurred by later changes. Early inputs include the build strategy with supporting documentation covering outfit, material supply, test and trials etc.

3

Specific details which could influence early design arrangements include plate sizes which could influence bulkhead spacing and modular equipment which could influence the frame and longitudinal spacing (via mounting requirements).

4

Similarly the adoption of a building block approach could well entail arrangement tradeoffs to facilitate the joining of outfitted blocks.

5

It should be borne in mind, however, that design for production issues must be carefully balanced against operational aspects. Failure to do so will produce a cheaper ship, but a ship in which the primary functions of the vessel and transverse aspects such as survivability are severely compromised, a situation which is likely to persist throughout the life of t he platform.

3.2.10

Safety

1

In law all employers owe a duty of care to their employees, the general public and the wider environment. For the Ministry of Defence (MoD), there is also an obligation to manage the greater safety risks associated with military operations. The Safety Management System should cover the protection of people, property and the environment. It should ensure that the hazard to people, property and the environment is not intolerable and is As Low As Reasonably Practicable (ALARP). Environmental impact is highlighted separately to encourage recognition of the growing importance being placed on environmental management.

2

In addition to the legislative responsibilities, good safety performance will lead to confidence in the ship or equipment. Thus an effective safety culture is key to sustaining morale, results in reduced costs of ownership and is an essential ingredient for achieving military objectives and business efficiency.

3

The management of safety as a transversal is expanded in Section 3.3.212.

3.2.11

Supportability

1

Supportability covers availability and requirements for fuel, lubricants, self maintenance, shore side support and preservation. In an ideal world, a warship would be permanently available to fulfil its role. In reality, however, there will be times when it is not fully operational due to refit, repair or equipment failure. The shorter the time spent out of service the fewer ships required to fulfil a given requirement. Ship availability is a major cost driver and the means of maximising availability should be considered from the outset and throughout each stage of the design process. All too often supportability requirements have been compromised in an effort to reduce the Unit Production Cost (UPC), when new building budgets are constrained.

2

Through life costs greatly exceed initial acquisition costs and careful consideration must be paid to factors influencing them. One immediate factor is that limits may be placed on the choice of equipments to be fitted in order to maintain commonality with existing plant in-service with the fleet. There may well be trade-offs between the ability to exploit new technology, the costs of introducing more variety in to the supply chain and the desire to avoid the problems and costs of block obsolescence. Advice from procurement and equipment specialists should be sought. Limitations may be expressed at the level of particular equipments or particular suppliers.

3

Another logistic factor that will impact on the overall design is the levels of repair to be undertaken on board. This affects not only the workshops, spares holding and hence stores space but also the composition of the crew and the facilities required for them.

4

Availability, Reliability, Maintainability and Testability (ARM&T) requirements should be integrated with the overall performance aspects and accorded comparable importance with cost, time and programme requirements.

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6

7

Chapter 3

Effective support can be achieved by: •

Maintenance-free design;

•

Selection of reliable components;

•

Improved maintainability by modularity access (maintain by replacement);

•

Provision of suitable maintenance envelopes and removal routes;

•

Selection of high reliabilit y equipment or redundancy;

•

Intrinsic redundancy in the equipment;

•

Incorporation of ‘testability’ as design objective;

•

Standardising and minimising the number of different fuels and lubrication oils carried.

The designer should be aware of the proposed maintenance philosophy and design-in any necessary facilities. A particular area needing design attention from the outset is the requirement for easy and safe access to all internal spaces, double bottom, tanks, cofferdams, sonar spaces, voids, etc., for survey. The effects on the design include: •

Trade-offs of cost (e.g. more cheaper ships or fewer very reliable);

•

Reliability - selection of equipment;

•

•

•

•

Maintainability – access to all parts of hull structure, space round equipment, and removal/repair routes - integrated policy; Stores and supply; Increased Fitted For But Not With (FFBNW) space (weight, power, cooling, etc.) allowed in design (the Board Margin); Balance to be achieved between levels of onboard spares and complement size.

3.2.12

Survivability

1

The survivability of a ship in battle, or any other form of damage, depends on three factors: •

•

•

Susceptibility - Defined as the likelihood of the ship being damaged in the first place and depends upon the success during the various stages of an engagement: detection, identification as target, acquisition by weapon and weapon hit. The first two are concerned with avoiding attack and the second two with defeating an attack. Whilst all may be achieved by a combination of active and passive means, the latter are probably dominant in avoiding attack while active means are significant in defeating an attack; Vulnerability - Defined as the ability of the ship to withstand a weapon hit or other damage measured with respect to its operational ability to fight, move and float; Recoverability - Defined as the ability of the ship to restore its capability after receiving damage to fight, move and float.

Susceptibility 2

Reduction of signatures will have major benefits by reducing the range at which hostile sensors can detect the ship. It will also make it easier for jammers and decoys to operate by reducing the size of effect needed to create to confuse a sensor. Other factors, however, should also be considered including: •

•

WEMG Issue 01

During peacetime it may be beneficial to be able to artificially alter a ship’s signature so as to prevent potentially hostile forces from collecting target data. The same approach may be beneficial in managing the countermeasures against an identified threat; The simulation of other ship signatures may enable the warship to blend in amongst legitimate traffic during covert operations.

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3

The imposition of signature targets will impact on all aspects of the design, and in most cases manufacturing costs, of the vessel. It is important that all sub-system designers are aware of the targets and the potential contributions that their systems could make. Unless this is done, expensive measures taken in the design of the sub-systems may be negated by one particular sub-system element. Conversely, if the limit on what is achievable is set by the characteristics of one particular system, it may be pointless to demand more from other systems and so costs may be saved.

4

One of the major difficulties with signature management lies with the prediction accuracy of the signatures sufficiently early for them to be used to influence the design. Analysis tools exist for most signatures but their accuracy depend on levels of detail that is unavailable early on, when the design is still fluid. Therefore, it is important to establish a relationship between designers and signature experts so that a graduated process can be adopted.

5

Initially best practice and guidance measures are established. As soon as general configurations become available preliminary modelling and analysis can be performed to check budget values. 9 As the design progresses, detail can be added to analysis models .

6

Processes for capturing and communicating data must be established so that problems can be identified early and solutions found. Signature management plans have proved to be effective and they should be based on initial modelling and, with refinement, serve to assist in the trade offs. Regular review of the implementation plan, up to build, ensures that the requirement is integrated into the design process.

7

It is very important to strive for the correct balance of signatures and to recognise that the law of diminishing returns generally applies. Expert advice should be sought to determine the optimum balance for a given project.

8

In many cases final acceptance of signatures against requirements is achieved by direct measurement on suitable ranges. Susceptibility – Active Countermeasures

9

In this case the main concerns of the ship designer, as with all combat system elements, are related to location to provide suitable fields of view/arcs of fire, avoidance of interference with other systems (EMI/EMC etc.), facilities to rearm quickly and safely, provision of suitable services, power etc, and convenient installation/removal (alignment, structural stiffness etc.).

10

Overall ship signature parameters of relevance are discussed in more detail below. Susceptibility - Radar

11

Radar Cross Section (RCS) is a measurement of the amount of incoming radar energy reflected back to the detecting sensor. This can be reduced in one of two ways, either reflection or absorption: •

•

12

Radar reflection: Controlling the directions in which radar energy is reflected back is the easiest, cheapest and most effective way of reducing a ship’s signature; Radar absorption: Materials can be made which absorb radar energy. Unfortunately their absorption characteristics are likely to be frequency dependent and they are often heavy. Their use is, therefore, best limited to palliative measures aimed at controlling mutual interference between the ship’s own systems if such problems cannot be eliminated by careful initial location.

The best way to control reflection, now almost universal for ships, is to control the directions in which radar energy is reflected by shaping the ship’s surfaces with flat faces so that energy is returned in a different direction to that at which it arrived (unless the direction is exactly perpendicular to the face). It is, therefore, essential that the number of different face angles is minimised and that faces are as far as possible parallel to each other.

9

How far this process is worth taking is a matter of judgement, as a law of diminishing returns applies on the cost and level of accuracy obtainable.

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13

It is important to avoid internal right-angled corners, which act in the same way as radar reflectors returning energy to the direction from which it came. Since a serious threat comes from sea skimming missiles, flare and tumblehome can be used to avoid reflection back to an approaching 10 missile seeker .

14

Radars operate at different wavelengths, long-range radars use long wavelengths and vice versa; therefore, different radars will be affected by different features of a ship’s geometry. All radars will be affected by efficient shaping, while for the shorter wavelength the finer the level of detail that must be addressed. The signature seen by short wave missile seeker radars will be greatly affected by the small detail fittings on a ship. This includes: •

•

•

Deck and superstructure fittings - These can be shielded by flat screens or made from non radar reflective materials such as c omposites; Aerial systems - Since these are designed to be efficient emitters themselves the only way to screen them is to place them behind frequency selective reflectors. These are materials designed to allow transmission of energy at selected frequencies but to reflect others; Radar transparent structural materials - Most composite materials are transparent to radar energy. Therefore, equipment inside a vessel will act as uncontrolled reflectors and scatterers. The inclusion of lightweight conducting material layers can turn the material into a reflector and so the composite structure can be treated exactly like a metal structure in terms of shaping, etc.

Susceptibility - Infra Red 15

Infra red sensors detect differences in temperature between potential targets and the background ambient temperature. Anything that causes such a difference should be reviewed if IR signature is to be reduced. •

•

•

IR Sources - The obvious major heat sources in a ship are the main and auxiliary machinery exhausts. However, the entire surface of the ship will be conducting internally generated heat and it is very difficult to insulate sufficiently to prevent this. Even the sunlight on the outside will warm the surface so that it contrasts with the sea surface. As contrast is the key, cooler than ambient areas will also be significant. Machinery air intakes can create a very significant cool spot, which stands out prominently in the IR band; IR Cooling - Reduction of signature will, therefore, depend heavily on reducing the temperature differences. Exhaust cooling can be considered but requires weight and complex systems perhaps high up in the ship, particularly for gas turbines. Diesels may be exhausted through the side or even below water, however, back pressure and acoustic signature concerns must be considered. The ship surface itself may be cooled by the use of water sprays. A ship’s wash down system will have an effect; Visual - When gun engagements were controlled by visual targeting, camouflage and smoke screening were essential features of a warship. The advent of radar negated such measures: however, the emergence of imaging seekers in missiles means that such measures may again be necessary.

Susceptibility - Abovewater Radiated Noise 16

10

The main source of above water noise is the main machinery. Exhaust silencing and isolation of engines from the exterior structure are the main mechanisms to control noise. Provision of longer transmission paths and changes of materials to provide extra damping together with insulation materials may all be used to provide a given effect. The measures will depend on the frequencies of concern, and it is important to properly treat all transmission paths if a prescribed signature level is to be achieved.

The effect of the sea, acting as a reflector, must not be forgotten.

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Susceptibility - Underwater Radiated Noise 17

Like radar, acoustic detection ranges depend on frequency. Long range at low frequencies and vice versa. Water is also a very effective transmission medium, although ranges will be strongly affected by variations in water temperature, with depth leading to multiple reflection paths and the phenomenon of ducting. The two sources of noise that must be addressed are: •

•

Underwater Noise – Machinery. Not only must the machinery itself be noise reduced and isolated from the hull, but any interconnecting systems must also be addressed. In addition, noise will be transmitted through the air and into the structure. All paths must be considered and appropriate measures taken to achieve particular targets. If the ship has quiet modes of operation then essential equipment may be placed higher up to ease isolation measures and elimination of transmission paths. This, of course, has an impact on ship VCG; Underwater Noise – Hydrodynamic. Propeller cavitation is the prime source, but other sources of cavitation, such as active fin stabilisers, can be significant and must not be overlooked.

Susceptibility - Wake 18

Wake signatures are of concern for two reasons: •

•

Underwater - In addition to the risk of detection there is a threat from underwater homing weapons, which effectively lock onto the propeller wake and follow it up to attack the ship. The propulsors are the prime source; Above water - Synthetic aperture radars are capable of detecting ship wakes from long ranges. Wake is affected by hull shape, but overall wash wave heights are really dominated by speed and displacement length ratio.

Susceptibility - Magnetic 19

Magnetic signatures are essentially short range effects and are significant with regard to the mine threat. Steel warships may be depermed or fitted with degaussing systems to reduce their signature. The latter have a significant effect on electrical system weight and are certainly a complicating factor in build.

20

If vessels are intended to go into mine fields to prosecute mines then active degaussing measures are insufficient and so extensive measures must be taken to reduce the magnetic material in the ship. This involves two main factors having a major bearing on material and construction costs: •

•

Reduction in the ferromagnetic content of the vessel covering structure and all equipment and fittings; Elimination of eddy current loops. Any loop or large area of conducting material will induce eddy currents to flow within it as it passes through the earth’s magnetic field. These currents themselves create a field effect and hence a signature. Countermeasures involve the break up of such loops with insulators, consequent duplication and separation of earthing systems.

Susceptibility - Underwater Electric Potential 21

Underwater Electric Potential (UEP) is the result of dissimilar metals under the waterline creating current flows through the water. The propulsion and cathodic protection systems are, therefore, the major factors and their configuration must be considered if UEP mine sensors are a threat. Susceptibility - Extremely Low Frequency Electric Fields

22

Extremely Low Frequency Electric Fields (ELFEF) are similar to UEP but their source is different. In this case a field created by the electrical system frequencies generated within the ship can be transmitted to the water if the hull does not act as a screening conductor.

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Vulnerability 23

If a ship is hit then the effect upon its capability will depend not only on passive protection, but upon the available operational systems after damage. Two aspects need to be considered; damage resistance (the ability to minimise the actual damage sustained) and damage containment (the ability to prevent the spread of damage). Most survivability design features affect both aspects to varying degrees.

24

Layout is one of the key factors to be considered in making the ship less vulnerable. Locating key spaces such as command centres, magazines etc, in positions that are inherently protected may conflict with both efficient operation and build requirements, but may confer significant levels of protection at little penalty in terms of weight and cost. Finally, crew survival in the event of a hit may mean that accommodation areas are divided throughout the ship.

25

Tools are available that allow ship (hull structure and sub-systems) vulnerability analyses, against particular types and levels of damage, to be performed. These tools cover resistance to damage, effects on equipment, system, personnel, explosive safety, consequential damage and recoverability. The same comments with regard to possible levels of fidelity and cost effectiveness made with regard to signatures also apply to vulnerability. At the early stages there is probably considerable benefit to be gained by relatively simple FMEA with failures determined from ship location/damage area. For vulnerability, analysis is the only method available to assure the design against any set threat apart from expensive tests on limited representative test sections.

26

The main causes of damage and the measures needed to counteract them are described below. Vulnerability – Shock and Whipping

27

The degree of shock resistance that must be achieved by equipments is represented by two factors: •

•

Shock factor - A measure dependent on size and distance away of a specified charge of TNT; Shock grade curves - Shock requirement for equipment dependent upon the severity of the threat, related to shock factor, function of the equipment and location of the equipment within the warship.

28

The hull structure will be subjected to local pressure loads and overall whipping. This could be a driver in determining structural arrangement and scantlings and indeed may place a limit on major hull geometric proportions.

29

The effect on structure of increasing shock standards is minimal on scantlings but is predominantly seen in the areas of seatings and structural detailing. Parameter Primary structure Joint detailing etc.

Seating

Equipment

Systems

Effect of increased shock standard Very little effect on overall weight. Discontinuities such as breaks of focsle should be avoided where possible. Well-designed connections have a good intrinsic shock performance. Structure designed for good fatigue life generally performs well under shock. If deflection is acceptable, within the seat component, then inter component clearances become important. If deflection is not acceptable then there may be a weight penalty. Some cost impact arising from the need to mount equipment, although changes to the level of protection do not significantly alter the cost once the decision to shock mount has been made. Minor effect on space and clearances. Move away from bottom, bulkheads and sides to increase transmission path. Requirement to ensure retention of equipment leads to increased number of mountings and hence some increase in in stallation costs.

Table 3.1 Effect of increased shock standard on design parameters

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30

Equipments themselves will have an inherent level of shock resistance but may require mounting on shock mounts to reduce the accelerations experienced. Increasing the length of transmission path by mounting high up in the ship or away from the sides will reduce the level of shock experienced.

31

Much naval equipment is intrinsically ruggerdised, requiring only suitable mounting. For the rest there is a cost trade-off between higher standard of equipment, or more elaborate mounting of lower standard equipment. However, it should be noted that commercially available mounts are available that can provide acceptable shock environments for most items of COTS equipment. Vulnerability – Flooding

32

The selected standard will drive the specified damage length and/or number of compartments in which flooding can be tolerated and hence number of watertight bulkheads required, position of damage control deck and additional factors such as zoning configuration, limits for penetrations, and downflooding points. It should be noted however that vulnerability requirements are, in general, not the drivers for resistance to flooding and that established standards specified by the Naval Authority lead to the need to consider equivalent or more stressing levels of flooding.

33

The layout of the ship will be driven by the positions of watertight bulkheads. These affect not only the layout of compartments below the damage control deck but above it as well because of the need to maintain structural continuity through the ship. Furthermore, systems are not permitted to penetrate certain watertight bulkheads and so require vertical routes. Other systems require watertight glands and/or isolation valves to be fitted on both sides of watertight boundaries. These should be minimised as much as possible since the incorporation of remote operation for valves is expensive.

34

These factors are covered in the stability standards which deal with such issues as residual stability requirements and the acceptability or otherwise of active systems such as ballasting or fluid transfer to control the effects of flooding. Ballast systems to remove floodwater are also covered.

35

Damage control centres, at which repair stores are available, will need to be sited within the ship. Preferably these are towards the ends of the ship, and should have ready access to the upper deck to allow crews to gain periodic relief from what may be unpleasant conditions below. If portable pumping systems are carried, then sufficient clearances for access, to where they may be needed, must be provided. Vertical access may be very difficult considering the size of some such units. External fore and aft access is also highly desirable so that damage control parties can move along the length of the ship even if there is a fire blocking internal access. Vulnerability - Blast

36

Internal blast, arising form a hit by an anti ship missile, shell or air dropped bomb, is likely to have a significant effect on the float, move and fight functions of the vessel. Measures that could be taken to reduce the effect include: •

•

•

37

Specially designed bulkheads, with particular attention to their connection to the rest of the structure; Intentional blast routes and blow out sections; Barriers and discontinuities such as “dog-legs” in undesirable blast routes such as passageways.

Specification of precise blast levels will depend on threat assessments.

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38

With relatively minor modifications, the blast resistance of traditional steel structures can be significantly enhanced, with little or no increase in cost or weight. There may be additional considerations required in terms of siting equipment on or close to blast-hardened bulkheads. Blast hardened doors are available that offer significantly better performance over conventional watertight doors. In addition, there are issues raised when materials other than steel are considered, although the degree of performance drop-off shown by moving from a steel structure to, say, a composite structure is not necessarily as great as might be imagined, and in many cases the increase in vulnerability arising from a move to alternative materials can often be recovered through careful system layout and local hardening.

39

Factors to be considered when determining a blast management strategy include the threat levels, blast routes, blast release mechanisms, blast blockers, joints, system protection, Ordnance, Munitions and Explosives (OME) and OME protection and the effect of material choice on overall ship size and cost. Vulnerability - Ballistic (Projectiles and Fragments)

40

Fragments may not only be from the weapon but also from damage to the structure and equipment of the ship itself. These may penetrate bulkheads and cause damage at a considerable distance from the initial hit. The characteristics of the structural material are a factor in the creation of fragments, composites being somewhat better than most metal structures in this regard. In addition to the primary structure, consideration must also be given to selection of materials for secondary structures and linings in order to eliminate the potential creation of fragments.

41

Protection of critical spaces or systems can be achieved by two main methods: •

•

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Armour - Provision of armour is aimed at defeating small calibre weapons (typically small arms up to 30mm HE rounds) and fragments; defeating larger weapons or missile warheads is impractical because of the considerable weight involved. When considering small arms threats it is important to specify weapon stand off range and projectile type (e.g. Ball round, Armour Piercing) as well as calibre when specifying armour; Location - Siting spaces below the waterline gives the best protection but may not be desirable in some cases for other reasons such as system routing and ready access. Above water critical areas may be shielded by less critical spaces such as access passageways or storage spaces thus providing at least another layer of protection of structural material. Critical systems should be duplicated and arranged so as to minimise their vulnerability.

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Vulnerability – Fire 42

Explosive weapons invariably initiate fires fuelled both by materials in the ship and by unused fuel from the missile itself. Fire countermeasures take two main forms: •

•

43

Passive - There are two drivers to consider for passive systems, maintaining structural integrity and prevention of fire spread. A passive approach covers low combustibility 11 12 materials , fire zones and insulation . Insulation may, therefore, have different roles for different structural materials. It must be remembered that an initial weapon explosion may affect the insulation itself. The main barriers to the spread of fire will be the insulated fire bulkheads dividing the ship into fire fighting, damage control and NBCD zones. Zone boundaries will, ideally, be made blast resistant in order to maximise the ability to retain zone boundary integrity after damage. The need to maintain structural integrity long enough to extinguish the fire or evacuate the area will require insulation on all structural materials, including steel. This entails weight and is a factor to consider when using lightweight materials. Modern insulation systems are, however, much more effective and lighter than more traditional systems and should be considered. Important considerations in the use of insulation include the need, or otherwise, for boundary cooling, the retention of heat in insulation systems potentially causing re-ignition of the fire and an effect on flood control measures, i.e. patch repairs. Regulations on ignition, spread of flame, smoke emission and toxicity will have an effect on material choices. This particularly affects insulation and linings and is also a driver in the use of composites; Active systems - Various systems can be specified for fighting fires in different locations and for providing cooling where necessary. Such systems include water, water mist, gaseous, foam, etc. and may be either automatic or require manual intervention. All such systems need protection and redundancy in order to increase the chance of their being available after damage. In addition to the direct fighting of the fire indirect measures such as smoke clearance systems, an HVAC function, may be needed. In all cases system design will depend on the locations of the major fire/smoke/damage control zones.

The balance between active and passive fire fighting systems and the manpower on board required for fire fighting will require careful consideration. Damage control is a key driver in setting manning levels. Vulnerability - CBRN

44

Chemical, Biological, Radiological and Nuclear protection (CBRN) entails ensuring that potential contaminants, radiation, radioactive materials or disease agents do not enter the ship. The provision of a pressurised citadel, further sub-divided in larger vessels, is intended to ensure that even in the event of accidental opening, integrity is maintained. Controlled access points provided with air locks and wash down facilities at the re-entry points will be needed. The extent of these citadels, the conditions and times for which they must be maintained within them, needs careful consideration as they place a considerable load on air filtration systems. If machinery spaces are included within a citadel this effect is very significant and intake air must come from outside the ship.

45

External wash down facilities will be needed to remove contaminants from the surface of the ship. This will be an extension of the sea water system and may well act as the design driver for the system capacity. Clean exterior design and the avoidance of water traps become very important.

46

Factors to be considered when laying out a ship include the number of zones, the positions of air filtration units in each zone and associated cooling and distribution systems and whether machinery space to be included or not. This last consideration is a major driver on the system capacity. Provision of engine air, cabling, control systems etc, are all factors.

11

Standards provide ample options for specifying and controlling the selection of suitable materials throughout the ship. Required not only to prevent combustion of the structural material itself but also to prevent the transmission of heat and subsequent spread of the fire. 12

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Vulnerability – System Design 47

The post hit capability of a vessel is dependent not only on the ability of the ship’s structure to withstand and restrict damage, but also by the design and layout of ships systems. The use of an effective layout policy in concert with good structural design, blast protection and ballistic protection, will maximise post-hit capability, often at low cost and impact on the design. Conversely, poor system layout can effectively eliminate many of the benefits that are achieved through the use of other vulnerability reduction features.

48

System design can be enhanced by following some simple rules: •

•

•

•

•

Redundancy - key elements of vital ships systems should be duplicated where practicable. For example, combat system and platform management systems highways should feature at least two, and preferably three “legs”; Dependency and concentration - If elements of a system are dependent on each other it is better to locate those elements as near as possible to each other. That way, the area of damage that will render the complete system inoperative is kept to a minimum. As far as possible such sites should be in areas of low probability of damage or perhaps protected in some way; Reduction in critical elements - the number of elements that, if damaged, would lead to system loss should be minimised; Separation - If elements of a system are duplicated then the duplicate elements should be separated as far as possible in order to minimise the chances of one hit rendering both elements inoperable; The above points apply equally to interconnecting elements such as pipes and power cables, which must be routed in separate regions of the ship.

Recoverability 49

A key characteristic of warships is that they are intended to be able to recover from damage and continue operating as far as possible. This ability to deal with damage after it has occurred, damage control, is inherently manpower intensive and can be a major driver on crew size. However, the pressures on manning may be r educed through increased levels of automation and other applications of developing technology. It is difficult to quantify the manpower required as a function of particular design features; however, damage control can be eased by good design. Features which should be considered will include: •

•

•

Removal of flood water, smoke and contaminants; Reconfiguration of systems and supplies either by switching/re-routing for most systems or provision of temporarily l aid cables for power systems; Repair where possible of structure and equipment.

3.2.13

Upgradability

1

As a consequence of the long platform life, the capability will probably require upgrading. This could be carried out progressively, through As+As, or as a life extension or refit.

2

Simplistically the upgrade should be considered as a project transiting the CADMID cycle in its 13 own right . Thus includes provision of through life margins, modularity etc.

3

A common problem is the tendency to fit more electronics, over the life of the warship, without taking account of the additional heat load. This implies that the margins must be allocated down to the equipment, rather than maintained at the ship level.

13

With the warship being a given c omponent.

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3.3

MANAGEMENT OF TRANSVERSALS

3.3.1

Introduction

1

Transversals are the characteristics or properties of the ship that impact on all aspects of the design. They are specialised subjects, subjects, with their own domain experts and sources of expertise. These features mean that their consideration and management requires communication between many agents and equally, configuration configuration management of any data passed passed between them. Central project control is essential t o integrate the transversals and the design concept.

2

Transversals that require management across the various warship acquisition activities include Human Factors, Safety and and Support. These are described described below.

3.3.2

Human Factors Integration

1

Human Factors (HF) is the systematic application of relevant information about human capabilities, limitations, characteristics, behaviour and motivation to the design of products and systems, the procedures procedures people use and the environment environment in which they use them. The term covers all biomedical and psychosocial psychosocial considerations. This information serves as the basis for making design recommendations and for predicting the probable effects of various design alternatives. In addition, HF involves the evaluation of things that have have been designed designed to ensure that they satisfy their intended objectives. They are divided into seven key domains: Manpower

2

After payload/cargo requirements, complement/manning levels and associated accommodation standards are the biggest space drivers and, will have a major bearing on the size and layout of the ship. Manning is the largest largest element in the through through life cost of the ship and so must be considered early in the design design process. Detailed manning models are available available but at the early stages of ship design they tend to be inappropriate as they require more information on ship equipment etc. than is available. Analysis of previous vessels and careful careful factoring is a safe approach but does not allow for f or fundamental changes in philosophy.

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A high level analysis of tasks to be performed in the various operating states will lead to the definition of a watch and quarter bill or scheme of complement. complement. Various factors must be considered: •

•

•

•

•

•

•

•

•

•

•

•

•

Organisation structure - This will determine the available available skill levels and their distribution distribution between ranks and department specialisations; Operating Operating philosop philosophy hy - The organisati organisational onal structure structure will reflect reflect the operational operational philosophies, however, if novel concepts and equipments are being considered more detailed task analyses may be required; Automation levels - Automation is often quoted as the panacea panacea for reducing reducing crewing levels but there are implications, notably the required skill levels for operators and maintainers; Maintenance philosophy - The level of maintenance and appropriate appropriate spares holdings will affect both maintainer numbers and skill levels required; Endurance - Traditional RAS procedures procedures and associated associated stores handling handling can place a large demand on manpower and could be relevant should numbers be reduced through automation of other activities; Damage control - This is a major driver driver for keeping up crew crew numbers since damage control, repair and fire fighting can absorb large numbers of personnel in action scenarios; Husbandry - General ship ship cleaning cleaning operations operations absorb absorb considerable considerable numbers of personnel. The effort should not not be underestimated, particularly particularly for ships spending long periods at sea; Training margins - Extra accommodation accommodation for both trainees and trainers is generally required. Provision of training training berths may be combined with the ability to cater for short duration additional roles for the vessel; Embarked Embarked forces forces - Although Although not part part of the ship’s ship’s complement complement they they require require accommodation areas and place demands on the hotel functions and store areas within the ship; Flexibility - Since warship tasking is becoming more varied varied and difficult to plan. Extra crew is always useful; Adaptability - As future warship tasks become become more uncertain uncertain and varied the ability to change roles may lead to increased margins being call ed for; Technology Insertion - If capabilities/equipments are to be added during the life of the ship then the crew requirements will need to be considered at the outset; Accommodation standards standards - Minimum levels of areas to be provided are defined in appropriate standards but consideration must be given to f uture trends.

Personnel 4

The Personnel domain covers human characteristics, attributes, skills etc. and their relationships to performance. These vary slowly slowly over time as living standards and society’s structures, structures, behaviours and aspirations change.

5

The range of crew physical characteristics is relevant when addressing internal layout, escape routes and accommodation, accommodation, workspace design and and equipment control. The successful design of deck-head height, step size, access and egress routes and operator and maintenance positions will be determined by the actual physical size of personnel. personnel. The reach envelope of users must be modelled when assessing the usability usability of equipment. Accommodation must be designed designed to cater for privacy and other requirements for mixed gender crews.

6

Skills and rank requirements are determined by the mission profile for the vessel, its equipment fit and operational demands. demands. It is important that the impact of the platform and the equipment equipment on skill requirements is clearly understood. understood. Training needs and and the Human Factors Engineering of equipment are both heavily influenced by the skills and knowledge required for operation and maintenance.

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Organisational and social factors will also need to be taken into account to encourage retention and prevent skills loss. The quality and design of living accommodation accommodation and operational operational spaces may influence attitudes to serving on board board and hence retention. The design of equipment and the workload associated with its operation may also influence job satisfaction. Training

8

A Training Needs Analysis (TNA) will be needed for each project and its development should start early, particularly if there are novel novel technologies to be incorporated. incorporated. It will affect, and be affected by, the development of of the scheme of complement. Factors to consider will include: •

Career structures;

•

Training scheduling within career development;

•

Equipment specific training;

•

Training establishments and facilities;

•

Simulators;

•

Documentation and handbooks;

•

On-the-job training.

Human Factors Engineering (HFE) 9

HFE is concerned with improving task efficiency. Ergonomic considerations drive ship layout and equipment selection at two levels: macro (whole ship level) and micro (equipment and working space level).

10

At the macro level the following factors are important: •

Compartme Compar tment nt interr interrela elation tionshi ships ps and acce access ss route routes s - There There are many many functional/operational links between compartments that must be considered when laying out the ship. The aim, from an ergonomics ergonomics point of view, is to ensure easy and and quick access for personnel, preferably through co-location or otherwise by means of straight access routes, either either vertical or horizontal. horizontal. These could include: include: Galley, mess spaces and stores; RAS, stores embarkation locations and storerooms; •

•

•

•

•

•

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Casualty embarkation and sick bay; Magazine and weapon stations; Specialist personnel accommodation and work areas, particularly on larger ships; Damage control centres and command positions.

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Map 01-020 Warship Engineering Management Guide Warship Engineering Management •

Zoning - The requirement to split the ship in to zones for damage/smoke/fire control purposes will have a major impact on how compartments are laid out in relation to each other. Care must be taken to ensure that zones are truly autonomous and that damage caused in one zone does not impact on capability in adjacent zones. Zone boundary integrity should be maximised through the use of blast resistant structure, fragmentation protection and fire boundaries. The lack of access through watertight boundaries will severely restrict interlinking of related compartments if they are low in the ship. Consideration must also be given to how the ship will function if a zone is lost. The provision of emergency operational and support spaces in separate zones may be required. There is also a case for splitting crew accommodation between zones for the same reason: •

•

•

11

Chapter 3

HVAC – The provision of suitable air conditioning and treatment facilities is important to crew comfort. There are choices between alternative systems, distributed/local cooling etc. and their relative impact on the crew under different operating and damage scenarios must be considered; Removal routes - Sufficient space and perhaps lifting/transporting equipment is needed to allow convenient and safe means of removing and replacing items for off board repair; Damage and fire escape - Provision of alternative means of escape from areas of a ship in the event of fire or other hazard should be considered at the beginning. On larger vessels with high numbers of personnel, analysis of personnel movement may be appropriate using dedicated passenger evacuation models developed in the commercial world. Such considerations may also apply to more routine operations, such as troop embarkation.

At the micro level the following should be considered: •

•

•

•

Equipment design and selection - While many issues of equipment operation are the province of the equipment supplier rather than the ship designer/system integrator, consistency and compatibility in operator functions and human interfaces across equipments is important; Detailed layout of compartments and working areas - While standards, linked to anthropomorphological data, can deal with simple dimensioning and positioning factors, operational and functional considerations may require more thorough analysis. Key compartments would be the Bridge, Combat Information Centre and Machinery Control Rooms; Maintenance envelopes - Factors include access for personnel safely, comfortable clearances for equipment removal/replacement, provision of lifting and transportation systems for heavy items; Unusual operations - The design and layout of equipments for ship specific operations may be linked with particular operating procedures and practices.

System Safety 12

Safety is an extremely important consideration in all ship and system design. While military operations are inherently hazardous, the design and normal operation of any system must be governed by the principle that all risks are tolerable and As Low As Reasonably Practicable (ALARP). There are Safety Management System (SMS) procedures that must be put in place to deal with hazard identification and logging, consequence analysis, likelihood assessment and mitigations.

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The policy and guidance on MoD safety and environmental management systems applied to shipping activities is defined through JSP430 – MoD Ship Safety Management. It is, therefore, a requirement that all MoD civilian, military personnel and defence contractors comply with this document when they are involved in MoD shipping activities. It is split into three parts: •

•

14

Chapter 3

Part 1 sets out the principles of safety and environmental management and is expressed in goal-setting terms. The policy laid out in Part 1 must be complied with; Part 2 provides more detail and guidance to Duty Holders and Commanding Officers on the implementation of the Policy. Part 2 does not prescribe methodology or techniques, but does provide the approved baseline standard for anyone assessing compliance with Part 1;

Part 3 are Naval Authority Regulations which prescribe the methods to be used in the Certification of Safety for the Key Hazards for all MoD warships (surface ships and submarines) and covers: •

Stability;

•

Structures;

•

Escape and Evacuation;

•

Fire;

•

Munitions;

•

Propulsion & Manoeuvring Systems.

15

In addition, there is a requirement to ensure the ship is environmentally friendly, so far as is reasonably practicable, and compliant with appropriate legislation, both current and anticipated. It is the intention to meet a zero emissions policy, aspiring to zero emission fuel clean up and integrated waste management.

16

Further specialist advice on the management of safety should be sought from the MoD specialist ship safety management organisations. Section 3.4 provides a discussion on the standards for safety.

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Health Hazards 17

Apart from the imperative of avoiding any risk to health, operational efficiency is enhanced through provision of suitable working conditions. Maintenance of a favourable environment through adequate heating, ventilation and air conditioning and avoidance of hazardous substances are usual but, in addition, factors particular to ships must be considered: •

Ship motion effects - Standards prescribe limits on what is acceptable, based upon 14 experimental tests, but generally do not take into account the effects of habituation . Two considerations apply: •

•

•

•

Firstly, placing personnel in the ends of the ship is to be avoided, as vertical motions are far more severe. Similarly locations high up may cause problems due to roll induced lateral accelerations. The preferred location for manned areas is towards the middle of the ship; Secondly, frequencies as well as amplitudes of motions are significant to humans15. A longer period roll is more acceptable than a lower amplitude high frequency condition with high accelerations. This is a particular problem for hull forms with very high inherent stability such as catamarans.

Noise/vibration etc. - Propulsors, main and auxiliary machinery are the main sources of noise and vibration on a ship. Accommodation or permanently manned spaces should not be placed adjacent to these sources. Noise specialists should be consulted since remedial noise control measures can be expensive in terms of both weight and cost. As with many specialist analyses appropriate levels of analysis should be used at each stage; Toxicity - Hazardous materials must of course be avoided and COSHH regulations apply. Also the risk of fire on a warship is high and materials that emit toxic gases etc. should be avoided.

Social and Organisational 18

This domain is the newest addition, in response to the organisational complexity that is a key feature of providing Networked Enabled Capability (NEC). These issues have always been an issue on platforms but NEC operations have increased their importance for effective operations. As such, it is still evolving, but includes issues such as: •

Shared situational awareness;

•

Cultural issues;

•

Trust and information sharing;

•

'Soft' interoperability;

•

Alternative organisational configurations;

•

Channels of communication.

3.3.3

Support

1

Supportability is defined as those technical and administrative requirements that contribute to effective material readiness, human support requirements, and the planning and management that occurs both before and during production, and throughout the operational life cycle of the ship, at all levels.

14

What is unacceptable on a short mission time ship may be quite reasonable for a long range, high endurance vessel where the crew become acclimatised. 15 This is accounted for in the calculation of some seakeeping indices such as Motion Sickness Incidence (MSI), the percentage of individuals likely to vomit when subject to a given motion for a given amount of time.

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2

It is based on a Logistic Support Analysis (LSA) and comprises the following interrelated elements: Availability, Reliability & Maintainability (AR&M), human factors, supply support requirements, support and test equipment, logistics documentation and technical data, computer resources (non-tactical/operational), configuration management, packaging, handling, storage and transportation, maintenance concept, facilities, software support facilities for updating and proving programmes, Through Life Cost (TLC) and obsolescence.

3

These requirements are discussed below under “design for support” and “design of the support”. Design for Support

4

Design for support requirements are defined as those that influence the whole ship design and hence must be inherent characteristics of the design.

5

The overall objective is to strike the optimum balance between UPC and TLC in order to reduce the ‘cost of ownership’. Unreliability, excessive maintenance and onboard manpower are major cost drivers and have an impact on the availability of the capability.

6

The aim should be to minimise complexity of maintenance by designing for: •

Compatibility among system equipment and facilities;

•

Standardisation of design, components, fuels and lubricants;

•

Interchangability of similar components, materials and spares;

•

•

Standardisation of doors, hatches and manholes;

•

Maximum use of new technology where cost effecti ve to do so;

•

•

7

8

Optimising the use of common equipment between ships.

Operational Availability is indicated by:

•

10

Ensuring that each system and equipment can be supported through life, if necessary from acceptance to disposal;

Availability, Reliability, Maintainability and Testability (ARM&T) requirements should be integrated with the overall performance requirements and accorded equal importance with cost, time and programme requirements.

•

9

Optimising the type and number of maintenance tools, accessories and support equipment;

‘Mean Time Between Failure’ (MTBF), which is a measure of reliability of a component or system; the objective should be to maximise this; ‘Mean Time To Repair’ (MTTR), which in turn drives maintenance downtime, i.e. the time for which a component or system is non-functional; the objective should be to minimise this.

To achieve an acceptable Mean Time Between Failure (MTBF), the following objectives apply: •

Maintenance-free design;

•

Selection of reliable components;

•

Improved maintainability by modularity access;

•

Selection of high reliabilit y equipment or redundancy;

•

Intrinsic redundancy in the equipment;

•

Incorporation of ‘testability’ as design objective;

•

Standardising and minimising the number of different fuel and lubrication oil carried.

Care should be taken when relying on reliability data from Original Equipment Manufacturers (OEMs). Claims from equipment manufacturers should be substantiated with historical operating data from the existing fleet.

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11

Although much can be done to reduce down-time for equipment repair, there still remains the problem of the hull itself. Periodic dry-docking is necessary to survey and maintain the underwater part of the outer shell. The advent of underwater engineering techniques may permit significant reduction in the need for this. The designer should be aware of the proposed maintenance philosophy, and design-in any necessary facilities.

12

Mean Time To Repair (MTTR) can be minimised by designing for rapid and positive: •

•

Isolation of affected system/equipment;

•

Identification down to a replaceable or repairable module or part;

•

Verification of correction and serviceability;

•

Identification of parts, test points and connections;

•

Calibration, adjustment, servicing and testing;

•

•

13

Prediction of degradation by condition based maintenance, Built In Test Equipment (BITE), etc.;

Change of components and equipment by minimising the necessity for special tools and facilities; Accessibility to all hull parts.

MTTR may be reduced by introducing equipment repair by Upkeep by Exchange (UXE). Ideally, equipment should be designed so that removal routes are via standard doors and hatches. For all larger equipment subject to UXE, a dedicated removal route will be entailed. Further MTTR reduction measures include: •

•

•

Provision of maintenance envelopes; Vertical alignment of hatches to facilitate the removal of equipment through more than one deck; Special rigging for equipment handling built in to the ship unless this is not practical or cost effective;

•

Sloped and removable ladders providing access to storerooms;

•

Soft patches for equipment which is not frequently removed and is of large size.

14

Testability may be implemented by the use of Built-In Test Equipment (BITE). BITE should be capable of both continuous monitoring of sub-system status and operator initiated testing. Sub system BITE should be capable of isolating faults to the lowest level of repairable item. A capability for displaying BITE results should be provided. Such displays should provide an unambiguous indication of sub-system status (i.e. operable, inoperable or degraded) and identification of specific units within the sub-system that have failed.

15

Human factors issues affecting ARM can be satisfied if the number, level and skill of trained on board personnel are the minimum required to achieve operational effectiveness by designing for: •

Logical function and task allocation;

•

Easy handling, mobility, transportability and storability;

•

Minimum numbers of personnel and maintenance specialities;

•

Simple and effective operating and maintenance procedures and instructions;

•

Maximising the use of automation;

•

Maximum use of commercial practices.

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Chapter 3

Maintenance engineering costs may be minimised by designing the maintenance system by adopting ‘Reliability Centred Maintenance’ techniques together with failure mode, effects and criticality analysis and the application of conditioned base maintenance. The following should be optimised: •

On-board maintenance;

•

Use and costs of spares;

•

Repair by replacement;

•

Built-in-test equipment.

‘Design of the Support’ 17

The principle aspects of ‘design of the support’ which affect the design and layout are: •

•

•

•

18

Support and Test Equipment (STE); Logistic Documentation and Technical Data (LDTD), both documentation and NonOperational Computer (NOC) resources in suitable locations throughout the ship; Packaging, Handling, Storage and Transportation. The design should ensure that packaged items can be transported on-board and ashore taking in to consideration safety, special storage conditions, security marshalling and climati sing.

The effects on the design include: •

Trade-offs of cost (e.g. more cheaper ships or fewer very reliable);

•

Reliability - selection of equipment (not much influence on GA);

•

•

•

•

19

Supply support - means of minimising mean logistic downtime by an optimised spares policy;

Maintainability – access to all parts of hull structure, space round equipment, and removal/repair routes - integrated policy; Stores and supply - again not a GA decision but affects it; Increased Fitted For But Not With (FFBNW) space (weight, power, cooling, etc.) allowed in design (or growth margin); Balance to be achieved between level of onboard spares and complement size – not decided by GA, but will be reflected in it.

Obsolescence affects all equipment, software, tools, processes, support products, standards and specifications. It is inevitable, potentially expensive and cannot be ignored, but its impact and cost can be minimised by careful planning. There are two principal obsolescence strategies that can be adopted: •

•

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A Reactive approach implies that obsolescence problems will be addressed as and when they occur. However, it does not mean 'do nothing'. The consequences of this approach are that the opportunity to employ inexpensive solutions is lost. Also, the cost in maintaining combat capability is higher and there will be delays in any repair process due to both funding and engineering constraints; A Proactive approach is recommended for new projects/programmes, which requires investment to find part problems early. Problem parts in the configuration can be identified and engineering and logistics solutions implemented. This approach allows planning for situations that are likely to occur and the subsequent resolution to provide a cost-effective and time-efficient customer-oriented product.

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3.4

STANDARDS

3.4.1

Introduction

1

In simple terms standards are constraints on warship design and are intended to serve three main purposes: •

Pass on good design practice that has b een proven operationally;

•

Ensure operational or logistic compatibility with other systems;

•

Ensure safety.

2

Standards are not a panacea for ensuring a suitable product. They must be applied to a project sensibly with a full understanding of all that is involved, the first consideration being the implications of specifying a standard.

3

One of the problems of over reliance on traditional standards, particularly military standards that have grown up over many years, is the degree of cross-referencing that occurs. It is, therefore, important to identify the relevant parts of standards. Equally if standards are selected from different sources or parts of standards used it is essential that all the standards elements specified are consistent with each other. The act of specifying just a few standards may unwittingly result in calling up a large number of others resulting in a huge increase in costs.

4

Broadly speaking civilian standards are concerned with safety, either of personnel or the environment. Military standards also consider military operational, logistic compatibility and through life issues. More recently the development and adoption by many navies of Classification Societies’ Naval Rules has introduced a new choice for the customer. As these Naval Rules evolve from their commercial origins they are extending their coverage from general safety and operation to encompass military f eatures such as weapon damage tolerance.

5

Historically, Classification Society Rules have been very prescriptive in their application, however, in recent years they have introduced an alternative approach to ensuring safety that relies on risk assessment and the production of a Safety Case for each project. This allows more freedom for innovative solutions, which the purely rule based approach tended to stifle. However, the amount of effort required for a full Safety Case approach should not be underestimated. There remains a need for the MoD to retain knowledge in order to ensure that such standards are not applied incorrectly.

3.4.2

Selection of Standards

1

The selection of appropriate standards as part of the process of capturing requirements and acceptance criteria is critical to the overall success of the acquisition of a warship.

2

Sources of standards for warship engineering extend from legislation and policies set by government through general international and national standards to military and warship specific standards. Generic guidance on the selection of standards for MoD use can be obtained from the Defence Standardisation organisation. Detailed guidance on specific standards and their application should be obtained from the sponsor of the relevant standard.

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Sources of Standards 3

For warships, sources of standards may include: •

Defence Standards (or Naval Defence Standards);

•

Books of Reference;

•

Maritime Acquisition Publications;

•

Joint Service Publications;

•

NATO Standard Agreements;

•

Classification Society Rules and Regulations;

•

British Standards;

•

International Standards Organisation standards;

•

Statutory Legislation.

4

When specifying standards early on it will inevitably not be possible to conduct a full cost effectiveness evaluation of the implications of each one and so it may be useful to classify them in the same way as for other requirements with such classes as key, mandatory, minimum, preferred, target and so on.

5

Furthermore, in selecting the best source of standards, it is necessary to consider the environment in which they are to be used. For example, if the MoD wish to acquire a support ship and the potential shipyards have a strong background in merchant shipping, they are unlikely to be familiar in the use and application of purely military standards. To then specify purely military standards may result in a high cost premium to cover the risk that the shipyard may misinterpret the standard. Assurance

6

7

8

In the selection of standards for warships, it is very important to consider not only the standards themselves, but also how they are to be used and how the MoD can gain assurance of compliance. Assurance of compliance covers not only safety aspects but all technical aspects that contribute to the capability as defined in the User Requirements. Technical and safety assurance, therefore, needs to address: •

Assurance that the design complies with the agreed standards;

•

Assurance that the materials and equipment used are acceptable;

•

Assurance that the warship is properly constructed and set to work.

This assurance is generally provided by a combination of internal MoD organisations and Subject Matter Experts, or external organisations (such as Classification Societies). Linking Standards to Requirements

9

In selecting standards, it is necessary for the MoD to ensure that there is a clear link between the User Requirements Document and the System Requirement Document (see Section 2.3). This will require a full understanding of user requirements expressed in capability terms and the relevant technical aspects of a warship that are required to meet the user requirements.

10

Moreover, MoD projects must also bear in mind that the defined User Requirements may make assumptions that a certain degree of performance is provided by the warship platform. For example, a requirement to maintain aircraft operations assumes that personnel involved are suitability accommodated to ensure that they are fully rested and alert when they are needed.

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Chapter 3

Pan-Fleet Coherency 11

Although MoD projects are empowered to identify the most appropriate standards that meet the needs of their specific projects, there may be certain standards that are required to ensure panfleet coherency in the solutions adopted. For example, the use of a single type of engine across the Fleet may well reduce the overall support costs. Safety

12

It should be noted that standards that support safety certification must be agreed with the regulator prior to a warship acquisition contract being placed. Risk Reduction

13

In order to maximise capability from a defined capital resource, it is necessary to manage risk in a controlled and timely manner. Industry is forced to include a premium in the programme cost if risk is carried late in the programme when the cost of rectification is high. It is, therefore, prudent to agree standards that lend themselves to progressive acceptance.

3.4.3

Civil Standards

1

MoD safety policy is that warships are to provide a level of safety that is at least as good as statute. Indeed, for certain aspects they are to comply with relevant legislation, notably for environmental protection. These are discussed in turn. Safety

2

The effects of legislation and a generally far more litigious society mean that navies must achieve at least the same levels of safety during normal operation as would be expected in the civilian world. Appropriate standards for safe operation must, therefore, be observed, either based on acceptable principles or a thorough safety assessment, unless there is a conflict with an overriding military need. Even then trade off studies must be performed and the ALARP principle applied to any operational hazard.

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Chapter 3

It is worth discussing a few aspects in greater detail as these impact upon the warship design: •

•

•

•

•

Stability - Stability is regulated by the Flag Administration. Generally military stability standards will be more demanding than those for the commercial world. However, there are cases where the converse is true. The use of high speed craft is more prevalent in the fast ferry sector, thus the standards are likely to be more comprehensive than those for the military. Certainly for a vessel not expected to operate in the front line civilian standards may be appropriate; Structure - Ship structure is regulated by Classification Societies whose rules for verifying structures have been developed over very many years for the commercial world. It is important to understand the assumptions inherent in the use of Classification Society rules. Warship rules are continually evolving and dialogue with the chosen Classification Society serves to ensure that sensible application of standards is achieved. This extends not only during design, but also in to construction, when the local site representative wields considerable discretion in how rules are interpreted and applied; Operational Safety - Civil legislation covers some aspects of operation namely navigation, ship boats and motions and vibration. With respect to navigation, many areas of the world are covered by local regulation and vessel monitoring systems. Increasingly compliance with these may require particular equipments to be installed. Boat operations have been traditionally inherently hazardous and are coming under increasing regulation. For the launch and recovery of boats, motion compensated single man operation systems are very effective but are heavy and take up a lot of space. Finally, legislation on exposure to motions and vibrations is becoming more stringent and wide ranging and could potentially aff ect many maritime operations; Habitability - Many vessels are expected to meet commercial standards on accommodation etc. e.g. Royal Fleet Auxiliaries (RFAs). These standards require far more space than has generally been provided for naval crews. Factors that appear in MCA standards include the provision of daylight; Fire - Fire is one of the biggest threats to life at sea and is covered by a range of regulations covering materials, systems and equipments. Appropriate standards should be selected but the underlying reasons behind them should be understood. Many commercial standards are stringent and are based on ensuring sufficient time for the safe evacuation of untrained civilians in the absence of trained fire fighting crews and systems. As recognised standards, met by many non-traditional naval suppliers, they can provide a useful criterion for the selection of suitable materials and equipments for warship use. Suitable sources of standards for consideration include the Maritime and Coastguard Agency (MCA), London Underground and the aerospace industry. It should be noted that there are considerable implications resulting from t he application of civilian standards. For example, the room three corner test for resistance to fire may not be met even by typical warship steel structures as the paint systems generally can cause flash over quite early in the test!

Environmental Protection 4

Compliance to national and international environmental legislation, regulations and other requirements require that warship engineering needs to work actively to reduce the 16 environmental impact . There are limits to this in respect of purely military functions involving munitions and conditions in which the vessel has suffered weapon damage.

5

However, in general, the warship will be engaged in both international shipping and specialised naval operations that involve the movement of large quantities of weapons, equipment, personnel and associated stores and fuels, which will cause emissions to the air and the sea. Limiting emissions involves the continued development and implementation of modern technology, education, environmental requirements and audits as well as review of suppliers. All stakeholders are to be aware of the commitment to environmental protection at all phases of development and deployment.

16

As well as the use of energy and natural resources during all phases of operations at sea.

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6

With the advent of the Kyoto protocol, and others, there is now a general acceptance that environmental concerns are real and that action must be taken. As agents of the government, naval vessels will increasingly be expected to lead in the adoption of good practice. There are sound reasons for doing this, as naval vessels may wish to operate in many countries’ waters, and it is essential that they are seen to be good neighbours adhering to local regulations and expectations. For example the Baltic is covered by very strict exhaust emission requirements.

7

This will have a major effect on machinery and auxiliary system design requiring space for additional equipment and storage space for waste. The same demands are, of course, felt in the commercial world, particularly the cruise and passenger industry, and here the pace of technological development is high with new systems being developed. Transfer to a military vessel may not be straightforward if shock requirements etc. are imposed.

8

Restrictions on waste disposal require separation, incineration, compaction and storage methods and machinery to be considered. In addition, overboard discharges are restricted and sewage treatment plants and even grey water control will be required.

9

Such regulation requires the use of inherently clean engines with advanced control systems and may also require exhaust scrubbers, either water based or with the addition of chemical systems. The latter requiring considerable weight and space high up.

3.4.4

Warship Standards

1

There is a wide range of military system standards available. All have been developed over many years and encapsulate much experience; however, they require continuous review which can cause problems. It is essential that only appropriate standards, and or parts of standards, are specified to ensure that costs do not spiral out of control. Military standards are intended to cover areas not covered by civilian standards particularly those concerned with operability, interoperability and survivability. Operability

2

A warship cannot always choose when and where it has to operate and so human performance under adverse sea conditions is of critical importance. Guidance on the implications of particular motion levels can be found in STANAG 4154 and should be considered when specifying motion and sea state limits. Ship size, primarily length, is of course the major factor in controlling motions although good layout, avoiding the ends of the ship for critical areas, can make a big difference. The use of active motion control systems can help but they are costly in terms of weight and space for passive systems and signatures for active ones.

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Chapter 3

Interoperability 3

Warships are required to operate with other units and there are a number of aspects to be considered that go beyond the requirements of the specific warship. These include: •

•

•

•

Ship Issues - Ships operate together both nationally and internationally and so compatibility, not only physically but also electronically, between appropriate systems is essential. Such systems include communication systems, weapon designation and fire control, Electro-Magnetic Interference and Compatibility (EMI/EMC), RAS and stores handling, aircraft, boats and embarked military equipment; Network systems - These are the ‘glue’, which hold forces together and are becoming even more paramount with the closer integration of combat system command and control across units; Logistics - Warships have to operate in any area of the world and the greater the variety of different systems and equipments that have to be supported the greater the difficulty in providing support. There are, therefore, difficult trade offs to be made between selecting equipments that would optimise the design or cost of a particular system, but that might introduce more spares in to the support organisation, or using existing standard items that are already in use; Obsolescence - Obsolescence issues are becoming an increasing concern and it is essential that ILS analysis is performed in parallel with design development, so that these issues can be addressed. Suitable interface standards should be selected at all levels in all types of systems so that commonality, interchange and obsolescence issues are addressed. These problems are of particular concern in computer and software based systems where the pace of technology change is extremely high and is far shorter than the operational life of a military system.

Survivability 4

Survivability is a key characteristic that distinguishes warships from their civil counterparts. Survivability covers susceptibility, vulnerability and recoverability. There are no “standards” as such, although guidance is available on how to determine signature targets and MOD is developing policy on minimum performance levels and design features that are to be achieved in future platforms. The effects on ship design are considered in Section 3.2.12.

3.5

WARSHIP PROJECT ACTIVITIES

3.5.1

Design Review

1

A Design Review is a formal, documented and systematic critical review of the design. The Design Review is the mechanism by which the Design Manager provides assurance to senior/programme management and the customer that the development of the design is acceptable. It differs from a Progress Meeting, which covers status, timescales and cost.

2

Design Reviews should be undertaken at predefined stages in the warship design lifecycle .

3

The objectives of Design Reviews are to ensure that:

17

•

All reasonable design options have been explored;

•

All contributory factors have been considered;

•

The design meets the requirements and obligations;

•

•

•

The design can be produced, inspected, tested, installed, operated, maintained and disposed of in a way that is satisfactory the customer, taking in to account time and cost constraints; There is adequate supporting documentation to define the design and how it is to be used and maintained; The design is coherent.

17

It should be recognised that the quality of the design is reflected by the quality of the review(s). Should the latter be deficient then the design and its programme cannot be assured.

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4

Design Reviews support a contractual review of the project so that agreed customer/business requirements/objectives will be met.

5

The principal inputs to the Design Review process are: •

Work and product breakdown structures;

•

Design baseline information appropriate to the stage o f the project;

•

Design Disclosure/Justification of the baseline;

•

Summary of the design work to be performed to complete;

•

Test Evaluation and Acceptance plan and any t est and acceptance records;

•

Risk Register and mitigation plans to assure success;

•

Safety Case and Hazard Log.

6

Formal Design Reviews add to the cost of the project and take time. The costs should be outweighed by the benefits, but must be kept to a minimum. Ideally, all risks should have been foreseen and a solution proposed by the design team prior to the formal review meeting.

7

In preparing for the meeting the design team will present the design and any proposals or views on the subjects covered. The chair shall seek to achieve a consensus. It will be expected that the participants will brief themselves thoroughly and probe for weak spots in the design, but at the same time to maintain objectivity.

8

The steps involved in planning and undertaking the Design Reviews are as follows: •

•

Define the product breakdown structure for the design: i.e. how the design is configured/developed and integrated; Agree the areas of risk with key stakeholders, identify where design reviews can help to ensure that risk is mitigated and explain how the risks have been mitigated to date;

•

Establish design timelines, milestones and the reviews required;

•

Define and explain the expected level of product maturity for each design review;

•

Plan the resources to attend the design reviews;

•

Produce a Project Design Review Plan;

•

Undertake the reviews at predefined stages;

•

Address actions/feedback resulting from the review.

Design Review Plan 9

The Design Review Plan must detail how risks are to be addressed in a logical and effective way to gather sufficient information on the maturity and efficacy of the design at major project design decision points in the programme. This should give confidence to enable an informed decision to be made on the release of the design to the next development phase. The plan should contain (or reference) the following: •

Product and work breakdown structure;

•

Responsibilities;

•

Review strategy;

•

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Design Review hierarchy/programme showing schedule of Design Reviews and their relationship to, or dependence upon, subordinate review activities and the acceptance process.

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Chapter 3

For each Design Review the following should be reviewed: •

Expected product/system maturity definitions;

•

Integration Risks and their mitigation;

•

Key Integration Parameters (KIPs);

•

The key requirements, key functions and critical design features, including success criteria & targets for each review;

•

Safety Case and Hazard Log;

•

Review Team composition.

11

Design Review planning, especially the initial review, is concerned with the identification of critical issues and how their maturity is to be verified. Initially, the plans will encompass key requirements and those issues resulting from early risk identification and analysis activities. The critical design features will evolve as the development progresses, and so the Design Review Plan should be expected to change.

12

An understanding of the project engineering lifecycle and product/system’s design composition should be established. Because it is the integrity of the integrated design we wish to review, the project Product Breakdown Structure (PBS) and the way each part of the design within that structure is developed and integrated provides the basis f or the Design Review hierarchy.

13

The PBS is a hierarchical description in terms of the product configuration items.

14

The product description changes in form through the life phases of the product: •

Concept;

•

Build instruction;

•

Build;

•

Operation;

•

Disposal.

15

Thus the PBS should be expected to change dependent upon the view and phase.

16

At the outset of a ship or submarine project, and whenever changes become necessary, the designer should consult with appropriate specialist sections and other centres of expertise when determining the following: •

•

•

•

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The planned Design Reviews and safety certification activity and the part these will play in the project's risk management strategy; The sources of technical or professional assistance, both internal and external, to be consulted and the requirements for support during the Design Review and acceptance process; The records which will be made to show that proper steps have been taken to ensure that the vessel being procured will be both safe and fit for purpose; The planning and resourcing or each technical or professional assistance (particularly non-project intramural effort) in the form of appropriate tasking agreements.

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Chapter 3

The Design Review 17

The selection of a suitable Design Review Chairman is critical to success. It is important that he has an in-depth understanding and experience. The Review Chairman, along with the Design Manager, will draw up strategies for the most efficient way of running the review taking in to account the following: •

Overviews of the design following t he Product(or system/service) Breakdown Structure;

•

Examination of high risk elements of the design;

•

Examination of integration issues;

•

Confirmation of the status of subordinate review activities;

•

Plans for product/system/service qualification and acceptance;

•

Best practice in terms of product/system/service design and process;

•

Progress against KIPs, key requirements, key functions and critical design feature targets.

18

In practice, the Chairman, supported by Engineering and Risk Management knowledge and previous Design Reviews will agree review “themes” with the Design Manager before the Review Team is selected. The task is then to match reviewers to themes and direct the team to verify the project’s assertions of maturity and to challenge the design approach in areas of perceived risk.

19

He will typically seek independent corroboration that will normally be provided by Specialist Sections and Centres of Expertise covering the following topics:

20

•

Structural Strength;

•

Stability;

•

Magazine Construction;

•

Escape and Rescue;

•

Shipborne Munitions;

•

Explosive Safety;

•

Marine Engineering, including Fire and Motion Safety.

The review Chairman should be free to seek appropriate help from elsewhere, including industry and other external specialist organisations. Update Design Review Plan

21

It is probable that over the design lifecycle that the review requirements will change. This is usually as a consequence of new risk considerations being identified or occasionally when reviews have to be repeated. When changes occur they must be incorporated in to an up-issue of the Plan and the updated plan agreed with stakeholders and then re-issued to the design team. Outputs

22

The outputs from the Design Review process are: •

A record of the Design Review with actions;

•

Clearance to proceed to the next stage of the design;

•

Actions to address shortfalls in the design or design documentation.

3.5.2

Design Records

1

Adequate documentation and record keeping are good engineering practice in all disciplines. As far as a warship design record is concerned the following principles apply.

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Chapter 3

Objective 2

The design records must demonstrate how the design was achieved. As such it should be a collection of live documents for the project itself and a valuable source of reference for the future. It should contain sufficient information to stand up to scrutiny of the way the project evolved and the decisions taken. Audience and Scope

3

4

The design records should be available for use by a wide audience including the project team, the support team, other projects and independent auditors and should contain or reference: •

URD;

•

SRD;

•

Design Philosophies;

•

Design Specification documents;

•

Assumptions made at each stage;

•

All design decisions.

The latter two items are the key element of the records. Any reports or studies used to inform or justify decisions made should be referenced. If there are no separate reports then the record itself should provide sufficient information to explain the reason for the decision. Medium

5

An important consideration is the medium by which the design records are stored. Traditionally it may have been stand alone documents, but careful consideration should be given to electronic formats. One thing to bear in mind is the likely future availability of referenced reports. Electronic document management systems may provide a solution and if so should be tied in to whatever is used for the whole project documentation system. Compatibility with arrangements for through life support is obviously a key concern with all document formats and media.

6

It should be remembered that the Design Records must be configured and stored for a minimum of the lifetime of the vessel i.e. in excess of 50 years.

3.5.3

Design Policies and Strategies

1

As the design progresses, various documents describing the approaches, guidelines and philosophies should be developed. These documents should describe how the Warship Characteristics, described in Section 3.2, are intended to be addressed. They should clearly state what will be achieved, strategies for doing so and, equally important, what will not be addressed. As such they must flow down from the requirements. Initial drafts of these documents will be very simple and high level but others will develop as the design and requirements mature.

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Map 01-020 Warship Engineering Management Guide Warship Engineering Management 2

Chapter 3

Documents or statements should include the following: •

•

•

•

•

Human Factors - Human Factors cover a wide range of disciplines including manpower, personnel, training, human factors engineering, system safety, health hazards and organisational/social. However, the main concern in early stage design is considered to be manpower. Manpower has the potential to dramatically impact and drive the ship size and it is important to have well defined policies regarding manpower to ensure manning is managed and maintained at appropriate levels; COTS/Development - The use of items under development will transfer risks to the timescale of the project. On the other hand Commercial Off The Shelf (COTS) or Military Off The Shelf (MO TS) may not supply the performance/capability required by the User; Structural Design - The structural style to be adopted will be governed by both performance and producibility factors. Most production facilities tend to be optimised for particular methods of manufacture, and changing may have cost implications. It may be more cost effective to limit design choice to easily produced configurations, but the implications of this on the overall design (e.g. a much heavier structure) need to be traded off and formally agreed; Hydrodynamics - The hydrodynamic characteristics and approach is influenced by the capability requirements e.g. the ship may be optimised for one of the following: •

Seakeeping;

•

Endurance;

•

Self noise;

•

Helicopter operations;

•

Resistance at cruise speed;

•

Maximum speed;

•

Survivability;

•

Ballast capabilities (e.g. for LPD).

Build - Build philosophy is a key element of the Acquisition Strategy adopted for the project. As such it embraces issues wider than the project under consideration and may not be under the control of the Procurement Authority when wider Governmental considerations are addressed. It will be closely allied to outfitting philosophy issues such as: •

Facilities assumed available;

•

Block sizes determined by build and outfit areas, cranes, lifts etc;

•

Block break positions and relationships with major compartments/system routes;

•

•

•

•

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Erection sequences and consequent effects on access for equipment installation; Open sky outfitting; Lockouts of compartments containing delicate equipment that cannot be installed late.

Survivability - Survivability policies often drive design features that have a direct influence on the initial sizing and layout out of the ship. If these policies are understood early in the design cycle, there is a greater opportunity that the required features and capabilities can be incorporated with minimal impact on the design and cost of the ship. Coverage should include: •

Above and Underwater Threats;

•

Post hit capability;

•

Blast management;

•

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•

•

•

•

•

Shock and Whipping policy;

•

CBRN policy.

Chapter 3

Some of these policies and features that should be defined early in the design cycle include shock levels, signature level targets, separation and redundancy arrangements, NBCD arrangements and protection schemes for magazines and vital operational spaces. See Section 3.2.12; Systems - Brief philosophy statements for the major electrical and engineering systems covering architecture types, reliability and availability, modularisation, compatibility and system routing, including survivability aspects; Through Life - Policy statements will be needed to cover the intentions with regard to: upkeep, base maintenance, onboard maintenance, repair, availability. Equally important is how any design effort, in support of these policies, will be funded. For example, reliability centred maintenance will require R&D to develop the test and monitoring equipment and processes necessary for future savings; Margins - Margin policies are fundamental to managing the design and must be initiated at the earliest stage of design development. Margins are a necessary element of every design and are used to account for uncertainties during the design and construction process.

3.5.4

Margins

1

A margin is the designer’s attempt to quantify the uncertainty and "risk" associated with the design. Margins or contingency allowances on weight, space and other design features are included in the ship design to reduce the impact of changes during design, build and in-service. These changes may arise from uncertainties in the design methods or data used in the earlier 18 stages, from agreed additions or alterations or from growth in-service .

2

It has become apparent that past Royal Navy (RN) projects have suffered due to the ineffective management of margins. This has resulted in reduced performance of the vessel due to limitations on weight, space, electrical power and other systems. It can also lead to the imposition of operational limitations through measures such as liquid loading restrictions leading to reduced endurance. Failure to provide sufficient margins can also lead to the vessel being unable to accommodate future change, upgrade or refit.

3

However, it must be noted that in order to rectify this problem, the simple answer of increasing the margin allowance in the design, is not necessarily correct. It is crucial to strike a balance between providing too much margin in the design and providing no margin at all.

4

During the early stages of design, the information available on specific ship systems sizes, weights and positions within the vessel can be vague, or not exist at all. It is commonly recognised that, as a new ship design progresses from conception through to delivery, the quality of design information available increases.

5

From URD (User Requirement Document) to delivery and in-service, the correct, consistent management of margins is key to obtaining and maintaining the required operational performance of the platform. Hence the setting and management of margins forms a crucial part of both the design cycle and the Through Life Management Plan (TLMP).

6

Failure to allow a sufficient margin can lead to major design problems at a later date; be that pre or post delivery of the vessel. When setting margins, consideration must be given to the practices being used, their accuracy and the experience of the users of these tools. Inaccuracies or omissions will always occur; it is having the capability to absorb these that is the issue.

7

It is not possible to control the margins that have been set at a single top level. To do so on a complex design would be impossible due to the amount of information required to control the weight, space and position of all equipment and structure across the entire design. Therefore, it is necessary to break the margin allocation and responsibility down into smaller sections. These can then be allocated in relation to the equipment and systems to which they relate.

18

Including those from the User Requirement Document (URD) or System Requirement Document (SRD).

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Definitions 8

The Capability Upgrade Margin (CUM) [Previously the Board Margin] is allocated to allow changes to be made to the operational capability of the platform from that specified in the User Requirement Document (URD) or System Requirement Document (SRD). The CUM is owned by Requirements Staff, as they control the capability requirement of all platforms within the MoD fleet. However, the CUM is monitored and calculated by the MoD Project Team who, on a request to upgrade or change the capability of a platform, would calculate the feasibility of the upgrade in relation to the remaining CUM.

9

Contract Modification Margin (CMM) - The CMM provides make changes to the contract. Such changes could arise changes to requirements or specification of the vessel or its to correct errors or omissions, from the SRD as well as specifications, which are outside of the contractor’s control.

10

Design & Build Margin (DBM) - The DBM allows for a lack of detail at the different stages of the design and build process that result in the need for estimates to be made. These estimates have possible inaccuracies associated with them that cannot be eradicated until construction drawings are produced and the ship built. The size of the margin used depends on the confidence of the information that has been used to produce the initial documentation.

11

In-service Growth Margin (IGM) - The IGM accounts for unattributable growth to the vessel throughout service. This can occur due to painting of the vessel, accumulation of dirt, undocumented minor repairs, unofficial modifications and the addition of equipment or tools deemed useful by the crew. The IGM should be reassessed after a major refit in relation to the new state of the vessel.

3.5.5

Interface Configuration Management

1

In order to control the many interacting design tasks, mechanisms must be put in place to control the interfaces between them. The data that describes these must be identified and subject to rigorous control. Authority to change and issue the data must be clearly defined and equally important all issues/changes should be communicated to those that use the data. An example of 19 some of the characteristics to be controlled in such a manner is shown in the table below.

19

an allowance for the IPT Leader to from revision of applied standards, equipment. The CMM can be used changes to predefined equipment

These characteristics must be supported by the allocated margins. Paragraph 3.5.4 refers.

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Map 01-020 Warship Engineering Management Guide Warship Engineering Management Data Mass properties

Electrical

Distributed fluid systems

EMC

Control systems

Space envelopes

Production and manufacture

Status of data

Chapter 3

Factors Weight Vertical centre of gravity Longitudinal centre of gravity Transverse centre of gravity Voltage Frequency Usage factor Physical interfaces Pipe sizes Flow rates Capacities Temperature Pressure Physical interfaces Frequencies Power levels Directionality etc. Screening Data Protocols Compatibility Input/output signals Processing speed Physical interfaces Fitting Removal Repair & maintenance Shipping Storage Preservation Lifting Installation Setting to work Estimated Calculated Supplier certified Measured

Table 3.2 Interface Characteristics for Co nfiguration Management 3.5.6

Effectiveness Assessment Objectives

1

The objectives of effectiveness assessment are: •

•

2

To quantify the benefit of a military system at a level which allows comparison between alternative methods of achieving that benefit; To allow the benefit of the system to be accounted for in higher level fleet or force level analyses.

The metrics used are Measures of Effectiveness (MOEs), which describe the military capability of the system. Before any effectiveness analyses are performed the approach to be used should be described in a Concept of Analysis document. This should describe the methods to be used, the sources of data and very importantly the assumptions and limitations of the analysis. It must be agreed with the customer operators to ensure its suitability, and must be closely tied to the Concept Of Operation (CONOPS) appropriate to the system. Where the CONOPS apparently precludes the use and appropriate assessment of particular options this must be raised with the customer.

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Chapter 3

The choice of MOE needs very careful consideration. It must be applicable to all possible options being considered. If there is any dependency on the option then the wrong MOE has been selected. This does not preclude different means of analysis for completely different option configurations. Generally MOEs are system level measures, MOPs sub-system measures. An example of selecting the correct MOE is: •

During the Second World War many British warships were fitted with the Pom-Poms short range anti aircraft weapon. This multi barrelled weapon was very inaccurate and expended vast amounts of ammunition. Analysts in the Admiralty looking at the costs of these weapons questioned ships in the Mediterranean convoys and asked how many enemy aircraft the weapons had destroyed. The answer came back virtually none. They therefore ordered the weapons to be removed. This caused uproar among the fleet. When questioned further they reported that once enemy aircraft saw the volume of fire and tracer coming from the Pom-Pom equipped ships they chose not to attack them and went after others instead! The MOE in the Admiralty analysis was, therefore, wrong. It should perhaps have been related to how many ships got through, not a measure of the Pom-Pom, itself only a sub system of the whole.

Inputs 4

In either case the data, on which the assessment will be based, will include: •

Environment in which the system operates;

•

Scenarios to be considered, including threats faced by the system;

•

Roles to be fulfilled by the system;

•

Other units with which the system interacts;

•

Performance of the system itself .

20

Methods 5

MOEs may be estimated using expert judgement but are more likely to be calculated using a suitable algorithmic representation of a military operation. Suitable calculation tools include spreadsheets or computer programmes implementing some sort of simulation using one of the following approaches: •

Analytic, probabilistic;

•

Event based;

•

Time step.

6

In each case sufficient runs will be needed to obtain a statistically valid answer. At all times the simplest model possible, that takes into account the factors of interest, should be used. Although correlation with real trial data is the best means of validating a model, sensitivity analyses can be used to help verification and gain confidence among real system operators that the model is a realistic representation.

7

Rather than just being used to quantify the benefit of a defined system, effectiveness models can also be used in reverse in that they can be used early on in the process to quantify the effect on benefit of changing a performance parameter. From such relationships target MOPs for the system and sub systems can be derived. Outputs

8

20

The outputs are: •

MOEs of the system in different environments, scenarios, roles etc;

•

Relationship between MOPs and MOE;

•

Target MOPs required to achieve a specified MOE.

Described by means of MOPs.

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Map 01-020 Warship Engineering Management Guide Warship Engineering Management 3.5.7

Chapter 3

Cost & Schedule Estimation Objectives

1

The objectives are: •

To determine all the costs, financial and non-financial, involved in the procurement, operation, support and ultimate disposal of t he system;

•

To determine the timescales required to complete the project;

•

To identify the risks to the validity of t he above estimates.

Inputs 2

There will be many sources of data but a pre-requisite for any estimation is an adequate definition of the system under consideration. This is given by two frameworks: •

•

3

4

5

6

Product Breakdown Structure (PBS) - Will define the configuration items which make up the product; Work Breakdown Structure (WBS) operating the product.

21

- Will structure the work elements involved in

Non-product material costs, such as facilities, jigs, consumables etc. must be included. Obviously the accuracy of any estimate is directly proportional to the degree of definition. Generally, in any estimate most of the cost is determined by only a few key factors and so long as effort is focussed on these, reasonable degrees of confidence can be obtained. The major cost areas to be considered are the acquisition costs and the Through Life Costs (TLC). The acquisition costs include: •

Project costs;

•

Research & Development Costs if appropriate;

•

Design and First of Class (FOC) costs;

•

Unit Production Costs (UPC);

•

Trials costs if not borne by supplier as part of F OC/UPC.

The Through Life Costs (TLC) covers: •

Operation - Manning, fuel and consumables;

•

Support - Facilities, spares, personnel, training, maintenance;

•

Disposal – Scrapping or residual value.

Estimates of cost and timescales must be derived from relevant data and experience. Since most companies are very protective of their cost data, suitable commercial arrangements may have to be established before appropriate sources of data can be accessed. Methods - Cost

7

Most estimating methods are based on Cost Estimating Relationships (CERs) derived from experience of similar projects. Ship construction costs are generally estimated based on the weight, adjusted for different type and construction phase. For warships this could be argued as being a somewhat gross simplification.

21

Note that Warship Project Management tends to confuse and combine the PBS and WBS or re-define the weight, in weight breakdown structure, as work. In ‘Traditional’ shipbuilding the work BS was closely related to the Cost Account structure of the yard. Thus, whilst it evolved for that particular yard, it was very different to that of another yard.

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Chapter 3

8

However, unless past data is available, re-examined and analysed there may be no alternative to using a global estimate. Therefore, it is vitally important to recognise how the new project differs and to attempt to make allowances. It is ill-advised to make assumptions in isolation of how the data was derived, and an appreciation of the issues affecting costs. For a ship build, how it is built is significant although, for warships, the equipment and its installation and set to work, is often more relevant.

9

Means must be found for accounting for facilities shared across many equipments or systems. Treasury accounting rules will dictate the rules to be followed in many cases. Similarly, all financial costs will need to be adjusted for the life of the project using appropriate methods such as Net Present Value (NPV).

10

As designs progress, cost estimation can be improved by obtaining quotations from sub contractors. As a general rule the cost estimate will follow the Pareto Principle where 80% of the cost is determined by 20% of the content. Methods – Schedule

11

Schedule estimates will depend very much on build philosophies and other projects running concurrently. Facility usage is often a key parameter and so discussions with potential suppliers will be needed. Key factors in achieving timescales may well be information and material availability from other projects and so close liaison between project teams will be entailed.

12

The cheapest and quickest build methods are those which allow work to be performed in the most efficient manner possible and with many parallel activities. Such approaches include:

13

•

Standardised elements;

•

Modularised units;

•

Completion of all hotwork before outfit;

•

Pre outfitting of panels before erection;

•

Outfitted units, blocks, mega blocks etc.

Conventional planning methods will determine the critical paths and overall timescales. The effects of uncertainties must, however, be investigated as the critical path will invariably be affected. Ideally, all information should be available before build commences, but this is generally unachievable for several r easons: •

•

•

Pressure to shorten overall timescale means design in totality is not complete before build commences; Pre-outfitting requires detailed information which is produced late in the design programme. Since the design and build schedules invariably overlap, there is a very important link between individual design, drawing and build elements, their management and the overall production schedule of the First of Class (FOC) vessel; Design changes.

Outputs 14

The outputs are cost estimates, schedules, uncertainties (and factors causing them) and risks to mitigate.

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Map 01-020 Warship Engineering Management Guide Warship Engineering Management 3.5.8

Chapter 3

Cost Effectiveness and Trade offs Objective

1

The objectives of the cost effectiveness task are: •

To provide a means of trading off cost and benefit in order to allow a selection to be made on the basis of best value for money between competing systems and sub systems;

•

To make a decision that is accepted by all stakeholders;

•

To provide an audit trail of the decision made.

Inputs 2

The inputs are: •

•

•

•

Costs - All cost factors should be considered, both UPC and TLC, financial and non financial if currency figures cannot be obtained; Benefits - Expressed in terms of military effectiveness. Figures may be required across a range of different environments, scenarios and roles; Assumptions - All data will have a degree of uncertainty. Some estimate of the likely range of values is useful to know so that it can be determined whether or not it may affect the ultimate decision; Risks - Estimates of risk consequences and contingencies should be included.

Methods 3

Many methods exist ranging from business decision-making criteria such as Maximin, Maximax, Least Regret etc. to complex black box computer methods. Whichever method is chosen, it is necessary to be able to account for multiple factors expressed in different units, and for the process to be auditable and be easily understood by all stakeholders so that they can accept the results (this requirement counts against black box methods that rely on extensive and complex algebra). In addition, it is desirable that the methods selected satisfy the technical criteria of consistency and coherency.

4

In the early stages of a project options can generally be eliminated on the basis of simple passfail criteria so long as the decisions are clear-cut. If they are closely comparable then options should pass through to the next stage. As more data becomes available and more factors have to be taken in to consideration, then multi criteria decision-making methods should be adopted. A wide variety of methods, all with their advantages and disadvantages, exist. Experience has shown that Multi Attribute Value or Utility theory combined with decision conferences satisfy all the above criteria and have proved themselves at all levels of the MoD. It is advisable to seek the help of experienced facilitators, at least initially, in the running of decision conferences as group psychology can be just as important in reaching a decision as raw data, and if this issue is not addressed then unsuitable decisions may be forced through. Although there are no formal procedures there are certain elements, which must be included, such as: •

Discussion and re-examination of issues;

•

Validation of assumptions and bounds of problem;

•

Derivation and cross checking of preferences;

•

Sensitivity analyses and exploration of disagreements.

Outputs 5


Decision accepted by all parties;

•

Audit trail.

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project

4

Chapter 4

THE PROGRESSION OF A WARSHIP PROJECT

4.1

AIM

1

This chapter outlines the activities that need to be undertaken during each phase of the acquisition of a warship. Furthermore, criteria to measure the maturity of a project at discrete milestones are provided in Section 4.14. These may be used to verify that a project is on course to successfully complete.

4.2

OVERVIEW

1

The objectives of the design activities within the context of a warship life cycle are to: •

•

•

•

•

•

•

•

2

Assist in the refinement of requirements to assure the viability and affordability (Cost Capability Trade-Offs); Identify the best potential solution t o an emerging requirement set; Establish a satisfactory basis for contracting design, production design and manufacture of the selected solution; Verify the feasibility to design a warship in compliance with agreed requirements and standards; Verify evolving designs against the agreed requirements; Validate the performance of the manufactured solution against agreed contract requirements; Maintain the effectiveness of the delivered product through life against the original and emerging requirements; Ensure the satisfactory disposal of the final solution at the end of its operational life.

A characteristic of warship design development is that it is essentially an iterative process aimed at integrating interdependent sub-systems into a coherent, consistent whole. This will inevitably involve numerous trade offs to deal with conflicting requirements both explicit and implicit. There have been many analogies used to describe the process. These include: •

•

•

Design spirals - The essential characteristic here is that a series of design tasks are performed, each dependent on initial assumptions, using data generated by a previous task and, in turn, generating additional information for a following task and proving the data on which tasks were based. The whole cycle can then be repeated based on better initial data and eventually converging on a balanced solution. This analogy, whilst emphasising the interdependencies, is rather simplistic and ignores the relative significance of the dependencies; Concurrent engineering - Is a strategy which replaces the traditional sequential product development process with one in which tasks are encouraged to be completed in parallel. This strategy focuses on the optimisation and distribution of resources in the design and development process to ensure effective and efficient product development; Design Structure Matrix - This considers the relative importance and consequences of the dependencies between design activities. This is presented as a matrix of the design activities against the relative importance of the interactions between corresponding elements. The matrix can then be used to rearrange the activities such that they are in the best sequential order. Such an approach becomes valuable when resources are constrained and complete parallel working cannot be achieved. Figure 4.1 shows the result of using this approach on a set of design activities A-I that cannot sensibly be performed in parallel. Optimisation to minimise the number of dependencies above the diagonal results in just three iterative loops required if the tasks are performed in the order F, C, E, B, G, H, A, D, I.

___________________________________________________________________________________________________________

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Chapter 4

Design Structure Matrix Entries reflect magnitude of dependency of Activity 1 on Activity 2 Tasks ordered to minimise strength of dependencies above leading diagonal

F

r e d r o y t i v i t c A

1 y t i v i t c A n g i s e D

F C E B G H A D I

Activities in sequential order Design Activity 2 C E B G H

A

D

I

� �

� �

�

� �

�

�

�

�

� �

�

�

�

�

�

�

� � �

�

�

In this case three iterative loops cannot be eliminated and so must be controlled in some way

Figure 4.1 Representation of Design Structure Matrix 3

In general the implementation and practice of design iterations is used to increase the level of maturity of the design and to correct design deficiencies that may exist in specific engineering disciplines. However, it is important that design development be carefully balanced against the quantity and quality of relevant design elements. For example, it would not be an effective use of engineering resources to perform a detailed layout of a machinery space if preliminary stability analysis has not validated the ship’s beam or sub-division spacing. As such, the design iteration process must be carefully managed at the total ship level to ensure that redesign efforts are minimised and changes are implemented in a well coordinated manner such that schedule is not impacted.

4.3

THE DESIGN REVIEW

1

A key element to managing the design iteration process is the effective implementation of Design Reviews. Design Reviews are a mechanism by which the Design Manager is provided with the current status of the key design areas. It is at these meetings that technical issues are discussed and critical decisions made regarding the focus of subsequent design iterations.

2

There are numerous mechanisms that may exist which would drive the need to perform additional design iterations. These mechanisms can be generalised into three basic categories:

3

•

Non-compliance with customer requirements;

•

Design standards;

•

Cost limits.

In areas where non-compliance is identified, additional iterations are required to correct the discrepancy. Once corrected, interdependencies must be reassessed to determine if the 22 corrective action or modification resulted in an adverse impact to any other discipline. Design iterations progress until an appropriate design maturity is achieved for the design phase of the programme. It is at this point that the design is considered to be “converged” and is ready to move into the next phase.

22

It can be generalised that a change in any one technical discipline will have a direct influence or impact on one or more areas of the design. ___________________________________________________________________________________________________________

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Chapter 4

4.4

CANDIDATE SELECTION

1

In the early stages of design a priority is to ensure that all possible alternatives and design solutions have been addressed with the alternatives determined to be feasible and cost effective to a level of detail to support a Combined Operational Effectiveness and Investment Appraisal (COEIA) process. This process requires an appropriate degree of system definition to be performed in order to generate est imates of: •

•

2

3

Capability and satisfaction of other requirements - System performance and characteristics; Through Life Costs - Manufacturing costs together with support costs obtained through ILS analyses;

•

Project Timescales - Covering development, design, production and trials;

•

Risk estimation.

Once the information has been generated, preferred options can be chosen. As options are eliminated the focus shifts to the management of technical risk and facilitate the accurate estimation of costs and timescales. The solution must be accurately defined to allow efficient manufacture, support and operation. Complete product definition essentially comprises three stages: •

System and sub system design to provide the performance;

•

Detail design to physically integrate the sub-systems;

•

Generation of manufacturing information.

4

The detailed work gradually shifts from a system perspective to sub-system and then to a spatial/location view of the physical product. This corresponds to the progression of activity from design to drawing office. As the product components are manufactured, assembled, Set To Work (STW) and trialled, the emphasis shifts back from location through sub systems to completed system. Each upgrade or refit through life will involve repeats of this cycle, but will continue to maintain design balance within budgets, i.e. stability, KG, weight, and the general arrangement (GA) to maintain design intent and balance.

5

The tasks to be performed are discussed in the following sections and can be defined as follows:

6

•

Option identification;

•

Design survey;

•

Design development & assessment;

•

System design;

•

Contract design;

•

Production Design;

•

Production;

•

Acceptance;

•

In-service support.

The relationship of these tasks to the classic V diagram is illustrated in Figure 4.2. Throughout the performance of these design tasks parallel activities are undertaken to support, monitor and control the work. These activities are listed below and described in Section 3.5: •

Design Reviewing;

•

Design recording;

•

Effectiveness assessment;

•

Cost and schedule estimation;

•

Cost effectiveness trade-offs.

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Chapter 4

7

The activities and organisations that actually perform these design tasks and how they are managed can vary greatly based on the procurement strategy selected for the particular project.

8

The most relevant document in the overall design process is the Ship Specification, which provides a description of the product to be supplied and the Measures Of Performance (MOPs) that it will be measured against under the contract. The Ship Specification is developed from the SRD which is a system solution to the customer requirements in the URD. Therefore, it is imperative that the Ship Specification and SRD are consistent and align in all areas. Contract Acceptance (CA) is performed against the Ship Specification and, therefore, by implication the SRD. In-service acceptance known as Fleet Weapon Acceptance (FWA) is performed against the URD and is determined by Measures Of Effectiveness (MOEs). This is generally demonstrated by a combination of operational trials (Part IV Trials) and analysis. These interdependencies illustrate the importance of maintaining consistency and tight configuration control over the development and management of these documents. The relationships between these documents and design phases in which they are developed is shown in Figure 4.2.

9

During early stages of design, tasks are primarily concerned with determining what the user wants, if it can be achieved, and what he can afford to pay for the product. In doing so it is necessary to make sure that the URD and SRD align so that a technical solution is both practicable and affordable. These stages will, therefore, require iteration as costs cannot be aligned directly with capability but must be estimated for an Architecture Design Description (ADD) generated to demonstrate how the performance could be achieved to provide the required effectiveness. This ADD is often known as an Indicative Design.

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Chapter 4

Option ID Design Survey Design Synthesis Design Assessment

Engineering Tasks

System Design Design Contract Design Production Design Production Acceptance In Service Support

Design Reviewing Design Recording Effectiveness Assessment Effectiveness Cost a an nd d Schedule Assessment Cost Effectiveness Trade Offs

Monitor, Support, Control Maritime System Maturity

1

2

3

4

5

6

7

8

9

CONCEPT ASSESSMENT

Procurement Phase

DEMONSTRATION MANUFACTURE IN SERVICE

Agency User

Define capability

Assured capability URD

Procurement Authority

Accept into service service

Define performance and architecture architecture

Final trials trials

SRD System Designer

Production

Sub-systems

Equipment supplier

Design system against performance performance

Design for production

Accept of offf contract contract ITEAP

Construction assembly

SATS

Inspection an and d HATS

Sub-system Installation Sub-system Installation Setting Setting design and test to work work Equipment manufacture under quality oversight

Figure 4.2 V diagram for Warship Design Tasks

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Chapter 4

4.5

OPTION IDENTIFICATION

4.5.1

Objectives

1

The overall aim of the first design task in any new project, is to identify all possible ways of meeting the requirement no matter how ‘off the wall’, and then to eliminate those that are simply never going to be practical. The objectives of option identification are, therefore, to: •

•

Identify all potential options - Initially to identify all potential technologies, design solutions, methods of operation etc. that could potentially provide the capability called for in the requirements. These technologies may be COTS or be emerging with the potential to deliver a solution within the project timescale; Filter out those that are impractical - To eliminate those options that are impractical because of performance, cost or timescale and to identify the particular reasons why.

4.5.2

Inputs

1

The major inputs are the capability requirement statements provided by the customer and his Operational Analysis (OA) studies. The latter in particular will need to be understood as they are inevitably based upon some gross assumptions.

4.5.3

Methods

1

In order to generate suggestions for possible solutions the following techniques can be used: •

•

•

Literature surveys - Information sources include technical publications, the Web and patent databases; Industry surveys - Requests for information to potential suppliers will generally provide useful information on existing products and plenty of assurances of capability to provide solutions! Brainstorming - At this stage the aim should be to bring in novel approaches and technologies perhaps from other engineering fields. In many areas the commercial world is well ahead in terms of technology and can often provide the basis for military systems at comparatively low cost and risk.

Use of commercial systems. The oceanographic survey industry developed autonomous underwater vehicles carrying sophisticated sonar survey equipment. These are routinely used for seabed surveys. They have now been tested and proved as highly effective tools for mine hunting. Coupled with sophisticated navigation techniques, again developed for commercial survey work, military requirements for mine location can be met with COTS technologies. 2

Included among the option list should always be the “Do Nothing” or “Status Quo” option or, if this is not practicable, the “Do Minimum” option. The latter may be to continue with existing equipment with some minimal adaptation.

3

Consideration of alternative hull forms could be part of the option generation stage. Most forms are optimised for particular characteristics and are very poor in other areas. This means that the more specialised a ship’s role and the more narrow its operating envelope, then the more likely that an alternative form may offer advantages. It is important that preconceptions about how operations are conducted are questioned in order to allow proper consideration of different approaches. Match performance of operational role and craft characteristics HMS Speedy was a hydrofoil purchased by the RN for evaluation. It was attached to the Fishery Protection Squadron and used in the same way as a conventional patrol vessel. Its design characteristics were, however, tailored to a sprint mode of operation and so were well suited to joint operation with other surveillance assets such as aircraft. It also required the Navy to man it in a different way to other ships with most of the maintenance being provided by a shore-based crew. The Navy could not adjust their policies to allow the craft to be used in the way for which it was designed and so it was deemed a failure and sold very quickly.

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project 4

Chapter 4

It is, however, important to eliminate impractical solutions as early as possible so that available effort can be focussed on more promising solutions. However, the reasons for rejection must be sound so that later scrutiny and questioning will not cause options to be revisited thus risking delay to the project. In all cases the aim is to identify potential ‘show stoppers’ that cannot be overcome without undue risk. Criteria to be used include: •

•

•

Performance - Assessment against key requirements. Simple Operational Analysis (OA) assessments with estimated Measures Of Performance (MOP) may be required. The OA models may be different for different operational concepts, but the Measure of Effectiveness (MOE) should be the same (Section 3.5.6); Cost - Estimated Rough Order of Magnitude (ROM) costs. This should not just be limited to the UPC. For example, if alternative hull forms are to be addressed, it may also include the costs of developing skills in the project team or of employing more study effort early on; Timescale - Expert opinion on key technology availability, development timescales and risk. Project design and build timescales cannot be properly estimated until there is an outline arrangement and high level equipment list together with likely delivery or lead time information.

5

Where many potential solutions exist with ill-defined parameters a decision conferencing approach involving relevant stakeholders and domain experts can quickly establish approximate cost benefit assessments that will enable the most promising solutions to be identified. At this stage only the really poor options should be discarded.

4.5.4

Alternative Naval Vehicles

1

The broad classifications of Alternative Naval Vehicles (ANVs) together with their main attributes are shown in Table 4.1. If intended to operate near to or above the hump speed (approximate Froude no. Fn=0.48) then hull forms will need to have high length displacement ratio or generate lift to reduce the weight carried by buoyancy.

2

Lift may be generated by planning hull forms or by other means such as foils, air cushions or airfoils. It should be noted that in all cases high speed requires lightweight construction. The table shows the major classification and more common hybrid forms but others are possible using a combination of support and r esistance reduction methods.

3

In comparing alternative forms parameters such as transport efficiency, which relate speed, carrying capacity and power can be useful but do not cover factors such as seakeeping, or layout limitations that are important to a warship. A more expansive treatment may be found in the 23 references .

4

Only the displacement monohull, with the possible exception of the trimaran/pentamaran which are better for stability, higher speeds, adaptability and helicopter operations, scores reasonably well in all areas. All the other forms have some disadvantages as the price for excellence in one area. The displacement monohull (or trimaran/pentamaran variants) is thus the most adaptable form if a range of tasks and operating profiles are required.

5

In addition to overall weight and payload fractions, another critical parameter to be considered is power density and the practicalities of getting the required power into the water or air. Conventional propellers give way to partially cavitating and fully cavitating propellers as speeds exceed 30 kts. Waterjets can compete on efficiency from 20 kts or so upwards while air propulsion only becomes worth considering at very high speeds.

6

A complication with most warships is that they are intended to be able to operate at a wide range of speeds making it potentially expensive in terms of fuel (or ‘payload’) if excessive optimisation for one speed is performed.

23

Listed in the Bibliography under Ship Desi gn, Section 6.1.2 ___________________________________________________________________________________________________________

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project 4.5.5

Outputs

1

There are two important outputs:

Chapter 4

•

Realistic potential system descriptions;

•

Justifications for rejection of unpromising systems.

Type

Monohull Displacement

Semi displacement

Planning Multihulls Catamaran

Trimaran

Pentamaran

SWATH Twin hull

More than 2 Hulls Foil supported Surface piercing Fully submerged Air supported Surface Effect Ship (SES) Air Cushion Vehicle (ACV) Wing In Groundeffect (WIG) Speed definitions Low Medium High

Major Characteristics

Potential speed relative to size

Seakeeping for size

Load Capacity for size

Generally round bilge form. Operate below main hump (Fn=0.48) unless fitted with large amounts of power (corvettes). Operate above hump speed but below planning (Fn=0.5-1.0). Lightly built with high M Significant dynamic lift from hard chine form (Fn>1.0). Very lightly built with low L/B ratio.

LowMedium

MediumGood

Very high

Medium

Medium

LowMedium

High

Poor

Low

Fine hulls for low wave making. Large overall beam for stability. High speed requires light weight. Fine hull for low wavemaking, stability from side hulls. Considerable structure in cross deck but high deck area. Same as trimaran but reduces drag and manages stability by raising two hulls in normal trim. Therefore, sensitive to load variation.

High

Poor

LowMedium

Medium

Good

LowMedium

Medium

Good

LowMedium

Reduced waterplane multihull to reduce motions. Large deck area. Sensitive to weight variation. Reduce hull size and uses high Fn and wave interference to improve performance.

LowMedium

Very Good

LowMedium

MediumHigh

Very Good

Low

Inherently stable, limited to low sea states. Tolerant of sea states but active control required. Weight critical.

High High

Medium Very Good

Low Low

Catamaran form with bow and stern seals, partly buoyancy, partly air pressure supported. Weight critical. Fully air supported with all round seals. Extremely weight critical. Amphibious if air screw driven. Airfoil operates in ground effect (within one chord length of surface. High power needed for take off. Potentially amphibious.

MediumVery High

Poor

Low

High-Very High

Poor

Very Low

Extremely High

Good

Very Low

Froude number Fn< 0.48 Froude number Fn 0.48 to1.0 Froude number Fn> 1.0 Table 4.1 Broad classifications of Alternative Naval Vehicles (ANVs)

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Chapter 4

4.6

DESIGN SURVEY

4.6.1

Objectives

1

The overall aim of this task is to understand and define the boundaries of the solution space for each major option. It must be recognised that the tools and methods may differ for each option, but the underlying objectives are t he same: •

•

Determine relationships between MOPs and MOEs; Assess effects of differing levels of specified performance, constraints etc. on system design parameters;

•

Define interrelationships of major design parameters;

•

Define boundaries of solution space;

•

Obtain ROM costing as function of major design parameters;

•

Select target design point in terms of performance;

•

Determine major parameters of ship to give target performance.

4.6.2

Inputs

1

Typical inputs to the Design Survey task are: •

Required capability;

•

Standards;

•

Constraints on design parameters;

•

Margin policy.

4.6.3

Methods

1

In any given design there are generally certain key design parameters that dominate the design and become the overriding concern. In ship design generally these are usually either weight or volume. However, for unusual vessels, often those heavily optimised for a specific task, some other parameter may dominate. For many warships upper deck length is at a premium and may dictate a minimum workable length arrangement. Such key design drivers, which will vary from design to design, should be identified very early on in concept work in order to bind any investigations.

2

Five main methodologies are needed: •

Effectiveness Assessment (Operational Analysis);

•

Ship Concept Design Issues;

•

Arrangement Studies;

•

Cost Estimation;

•

Cost Effectiveness Determinations.

Effectiveness Assessment (Operational Analysis) 3

In order to determine the effect of differing performance parameters or MOPs on effectiveness, Operational Analysis (OA) tools will be required (Section 3.5.6). The analysis models will need to be run repeatedly to establish curves of MOE as a function of different MOPs.

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Chapter 4

Ship Concept Design Issues 4

In order to perform this task thoroughly either existing data curves, derived from existing ships, or mathematical models, based on known data relationships, will be needed. Mathematical tools are likely to be either spreadsheets or integrated computer programmes. In either case, the key factor to consider and critically review before use is the base data and logic used to generate the algorithms used, and any assumptions inherent in them. It is best to create or modify any algorithms for a specific project so that they are tailored to the type of vessel under consideration, then conduct sensitivity studies in order to gain confidence in their behaviour.

5

Parameters that the algorithms will need to account for include: •

Deck/ship length elements;

•

Weight/VCG;

•

Space;

•

Stability;

•

Resistance and propulsion.

Ship Concept Design Issues - Deck/Ship Length Elements 6

There are certain key elements that must be included along the length of the ship. Some may share the same section of ship length but others cannot. Upper deck requirements will create a minimum acceptable overall length while elements such as machinery and hangar will take up particular parts of the internal volume. It is important to define their position in terms of length of ship occupied rather than a required volume: •

•

•

•

•

•

Payloads - Military cargo, landing craft, aircraft etc. may all place certain minimum length requirements on parts of the ship. These can be considered either as inputs to the mathematical model or constraints applied as a filter on generated results; Machinery Blocks - Although there can be a certain degree of latitude in arranging engines, gearboxes, etc. it is generally found that a limited selection of arrangements are practical for particular applications. Separate short investigations can quickly identify a range of possible available powers and associated arrangements to be considered. At the very early stages of concept design ‘elastic propulsion systems’ could be assumed, but even in this case, restrictions on machinery block size and location within the ship should really be accounted for. Factors to consider will include engine gearbox relationships, shaft lines (pods), uptakes/ downtakes perhaps placing further demands on available upper deck length, generator locations and the need or otherwise for Auxiliary Machinery Rooms (AMRs) within the main machinery block; Topsides Integration Factors - A major driver on upper deck length is the weapon and sensor requirement for clear arcs and the need to ensure adequate separation of the multitude of aerials found on modern warships in order to avoid EMC/EMI problems; Flight Deck - Helicopter landing, maintenance clearance and hangar size requirements are clearly defined for all aircraft. An additional factor is the location of the Air Weapon Magazine and its proximity to the hangar. The Air Weapons Magazine’s relationship with any ship launched torpedo weapon system must also be considered. The importance of the flight deck, hanger, magazine relationships obviously become greater for aircraft carrier (CV) and helicopter carrier (LPH) type ships; Seamanship Needs - Berthing, towing, sea boat and RAS operations all take up a certain amount of deck space and may need to be allowed for by specifying minimum available deck lengths and where those spaces are. For sea boats, factors such as launch/recovery, relative motions, heights, operator visibility, clearance from hazards etc. must all be considered; Operability - Additional restrictions may be imposed concerning the location of manned spaces away from ends of ship (because of ship motions) and upper deck access either side of superstructure to allow for stores handling and fore and aft movement for damage control etc.

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Chapter 4

As far as concept models are concerned, these requirements will tend to relate to superstructure position and size. It must not be forgotten that in some some cases many of the above above factors could also apply to a minimum beam constraint at some point in the ship. Ship Concept Design Issues - Weight/VCG

8

Weight estimation algorithms must be thorough and their derivation and ranges of applicability clearly understood. understood. Standard weight breakdown breakdown structures should be used to ensure ensure consistency. However, it must be remembered that warship warship design practices are continually continually evolving and any algorithms based on past data will need to be modified to reflect these.

9

VCG estimation can be very dangerous without an understanding of the likely layout. If similar ships are available than itit is relatively straightforward. If not, simple arrangement studies studies will be required in order to determine usable relationships that can safely be used. Ship Concept Concept Design Issues Issues - Space

10

Space within a ship is generally described either as volumes (usually reserved for fluids) or as deck areas (best (best used for compartments). compartments). Since deck heights heights are such a key parameter, parameter, affecting size of ship and production considerations, there is a strong argument for using algorithms that deal with deck areas explicitly in the model of hull space. space. This avoids the problem of generating hull depths incompatible with a whole number of decks with discrete deck heights and sensible double bottom heights.

11

Any calculation of space requirements must be checked with simple block level arrangement studies to ensure that it can be made available where it is required and can be used efficientl y. Ship Concept Concept Design Issues Issues - Areas

12

Although area breakdowns exist they are not currently maintained and so a consistent approach, to data gathering and algorithm generation, will need to be be readopted. Any breakdown should, should, as a minimum, at least identify: •

•

•

•

•

•

•

13

Operational spaces - On large ships where the the military equipment becomes becomes the reason for the ship’s existence, the ‘payload’ spaces will become the design driver and will generally need to be explicitly defined in the concept tool algorithms; Magazines - Including ready to use magazines, weapon lifts, etc; Accommodation - The grade or standard of living spaces to be provided provided must be considered. In some platforms platforms this may become become a cost cost driver; for example example when carrying embarked air air groups or military forces. Also, if modules are to be used, then allowances will need to be made for proper access both in use and a nd during build; Store and hotel functions; Services - To include such items as auxiliary machinery e.g. air conditioning and treatment plants not included in the main machinery block; Access, passageways passageways - Some means of revealing the effects effects of altering these, which have major operational operational and production implications implications is desirable. Horizontal and vertical vertical access routes and their links to system routes should should be considered. Access routes are fundamental to layout on all warships and their impact on the ship must be determined as early as possible. Access/system route choices choices such as side/central side/central passageways, vertical stairwells etc. will determine how space is made available and used for all compartments; Unallocated spaces spaces and voids - Future flexibility will require spare space. At this stage this could be accounted for through the use of additional margins.

Some caution should be taken to ensure that any multifunction spaces are counted once only.

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Chapter 4

Ship Concept Design Issues - Volumes 14

It is probably better to use explicit calculation methods based on powers, numbers of crew, ranges, endurance etc. to obtain fluid volumes rather than equations fitted to ship geometry parameters. The equations equations should, of course, be related to fluid weight weight calculations with standard allowances for structure and unpumpable volumes included. Ship Concept Concept Design Issues Issues - Stability Stability

15

The most convenient criterion for intact stability will be a required GM. However, GM is the relatively small difference of two large numbers and is prone to error if the VCG is not accurately assessed, or the the hull form not not accurately modelled. modelled. Stability calculations will thus require a reasonably accurate hull form to be assumed and a critical dependence on the VCG estimation. For damage, the same criterion criterion of a required intact GM can also also be applied. Experience of calculations for similar vessels will provide a guide to the sort of value of intact GM that will then result in the ability to pass damage standards, assuming an appropriate level of subdivision is provided. Excessive GM should should be avoided as a large beam beam is not only detrimental to the powering (for most monohull displacement vessels) but roll motions can be very uncomfortable, with a short roll period and high accelerations. Ship Concept Design Issues - Resistance and Propulsion Propulsion

16

Resistance prediction is best performed either by algorithms based on appropriate comprehensive standard standard series or on regression equations. Ranges of applicability need to be recognised. Propulsion analyses can can be fairly simplistic relying on overall overall propulsion coefficients derived from representative representative ships. Full and cruise speeds speeds are generally generally of interest as they are used to size the propulsion propulsion plant and calculate ranges or or fuel load required. The interaction between increased fuel load driving weight, weight driving resistance, resistance driving propulsion and this again increasing the fuel load is an example of a key iteration that will be considered in the concept design. Ship Concept Design Issues - General

17

The function carried out by a spreadsheet or programme is to systematically vary selected key input parameters and, for each combination of inputs, generate ship forms that balance weight, VCG, and space with the required stability.

18

The balancing tool will depend on its model of the configuration of the ship. This must be tailorable to allow for the particular particular style of the ship under under consideration. Style includes number of hull decks (including partial decks), superstructure superstructure configurations, etc. This will allow a set of parameters to be generated defining the ship envelope that will later allow for suitable treatment of: •

Structural arrangements;

•

Subdivision;

•

Embarked equipment or ‘payload’ arrangements;

•

Superstructure arrangement including hangar if required, bridge and boats;

•

Fore and aft deck arrangements;

•

Combat system configurations.

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Suitable constraints on overall parameter ratios, either in-built to the balancing process or applied as a filter on the output, will also be needed. Generally the following relationships will hold: •

•

•

20

Chapter 4

Draught adjusted to balance weight; Average double bottom height driven by tankage and associated cofferdams, voids, access and any system system routes. Deep tanks may need to be allowed allowed for in some way; Depth governed by deck heights/number of decks and the minimum sensible double bottom height;

•

Beam driven by stability;

•

Length varied to obtain deck area/length.

In generating the equations to calculate weight, space and VCG used in the balancing algorithms certain factors must be borne in mind. Obviously the basis ships must be closely related related to the new concept being investigated. investigated. However, changes may need need to be made relative to algorithms derived from type ship data to allow for: •

•

•

Classification - The effect of applying classification classification society rules to warship structure to provide robustness and longevity has invariably been to increase structural weight over the more traditional lightweight arrangements; Standards - Increased habitability standards (including separation separation of genders) genders) will generally lead to increased area requirements for accommodation; Producibility considerations (for example, modularity) - Deck height is a key producibility factor since system routes are generally generally placed on the deck deck head. The inclusion of cabin modules may also require an increase increase in deck height. height. Modularity generally will impose slight increases in area requirements to allow for module supporting structure etc.

Arrangement Studies 21

22

These are essentially early stage ship synthesis exercises concentrating on major general arrangement issues. There are three reasons for performing performing them as early as possible: •

Identify major arrangement drivers for inclusion in concept models;

•

Ensure space is available where it is required and can be usefully exploited;

•

Provide fixed points for partial p artial validation of trends produced by concept models.

For this reason they must be considered as an integral part of the process of using balance algorithm based concept concept tools. There are arrangement arrangement tools available, which help in performing performing these studies. In fact there should be strong links between between both types of toolset toolset as the algorithms for weight estimation etc. should be common common to both. The arrangement studies and and associated analysis should encourage an understanding of the drivers for the ship type under consideration, together with any unusual features being considered. Cost Estimation

23

Rough Order of Magnitude (ROM) costs are derived as functions of the major ship parameters using the methods of of Section 3.5.7. Care must be taken that simple simple concept tool definitions of of potential ships are not used as the basis of cost estimates without appreciation of what the parameters represent. represent. Simple arrangement arrangement studies and identification of major equipment fits should be used as the basis for costing and the trend data then used to help in limited delta estimation. Cost Effectiveness Determination

24

Suitable methods for selection of a cost effective solution are described in Section 3.5.8.

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Chapter 4

4.6.4

Outputs

1

The key output is definition of the major ship parameters required to give a target set of performance measures. measures. In addition, a plotted output, output, illustrating the sensitivity to varying varying input parameters, should show the key design drivers: •

Target performance parameters and resulting effectiveness;

•

Major design parameters, dimensions and installed powers;

•

Representative general arrangement;

•

ROM costs and indication of their variation with major design parameters.

4.6.5

Design Development

1

Design development is the process by which the user requirements are translated in to a design solution. It is used to raise confidence confidence in the high level Design Survey and to obtain data for more detailed costing and de-risking.

2

The principal activities performed during design development are broadly similar to those undertaken as part of the Design Design Survey, but to a greater level of detail. detail. Whilst at the Design Survey stage the designer may still be considering a number of options, by the design development stage the designer should have down selected to a maximum of two solutions, possibly with a few variants that will be further developed during this stage, in order to de-risk the programme. These variants variants will address various candidate candidate equipment options. For example, example, main propulsion machinery options or combat system equipment options.

3

By this stage the designer will be trying to place constraints on the solutions space in order to ensure that the design solution is realistic and achievable and can be procured within the required timescales and budgets.

4.6.6

Objectives

1

The objectives of the design development activities are to: •

•

•

•

•

•

Confirm the principal dimensions and main characteristics of the warship (e.g. length, beam, depth, draught and hull form parameters and overall ship configuration); Further define the interrelationships of major design parameters in more detail (e.g. the requirements for main machinery exhausts and uptakes may conflict with flight deck operations or mast and aerial lo cations); Determine major system parameters, for example the propulsion power of the main propulsion system and electrical generation capacity; Determine performance of the solutions, in terms of equipment configurations required to meet the required performance. performance. This may also require further development development of the relationships between MOPs and MOEs to a greater level of detail; Define major equipment to be fitted; Generate a more detailed general arrangement of the proposed solution showing the major compartments, access and system routes in outline and the interrelationships between these compartments;

•

Obtain data for order of magnitude costing based on the design configuration produced;

•

Develop outline acquisition programme;

•

De-risk design solution.

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Chapter 4

4.6.7

Inputs

1

The inputs for the design development task are basically the same as those required for the higher level Design Survey, but at a more detailed level, and include the high level warship requirements derived from the Design Survey. Survey. The inputs include: •

Major system parameters, including overall dimensions, displacement, powers, etc;

•

Guidance on the constraints, limits, r anges and tolerances of major parameters;

•

Performance ranges and effectiveness;

•

Identified key performance drivers and constraints;

•

Identified key integration risks;

•

Spatial interrelationships, including, location and overall size of machinery space blocks, accommodation and operational spaces and equipment;

•

Available sub-systems/major components;

•

Details of equipment likely to be fitted including combat system elements;

•

Refined capability requirement;

•

Standards to be adopted;

•

Margin Policy.

4.6.8

Drivers

1

The Design Drivers are similar to those identified during the Design Survey, but specific to a given design and at a more detailed level and adding: •

Sub-system dependencies and interrelationships;

•

Spatial relationships of equipment;

•

Dependency/Redundancy;

•

Co-location/separation;

•

Spatial relationship of compartments;

•

System Runs;

•

Human Factors;

•

Links to survivability.

4.6.9

Methods

1

A number of approaches are used to synthesise the design and include:

2

•

Empirical rules;

•

Basis ship type;

•

Historical data and experience;

•

Standards and regulations;

•

Bottom up design from first principles – deterministic rather than empirical;

•

Computer modelling;

•

Reference to manufacturers standard product information;

•

Costing and programme related to similar projects.

Design development is an evolutionary process that draws heavily on the collective design and operating experience of the MoD, Prime Contractor, Original Equipment Manufacturers (OEMs), design consultants and and other domain experts. experts. The starting point for the design design development is usually a basis ship, parametric or empirical analysis of a range of ships with a similar set of characteristics to those required to meet the operational requirement for the new vessel.

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3

The configuration is then reviewed by experienced engineers and operators to identify any characteristics of the design that are unlikely to meet the current operational requirement. Changes are then made to the basis design to meet the new operational requirement.

4

It is likely that much of this information and the empirical relationships will have previously been developed during the Design Survey phase. However, the data and logic used to generate the embedded algorithms and their inherent assumptions must again be critically reviewed in light of the emerging more detailed requirements.

5

Standards and regulations form an integral part of the design development process. Standards (Defence Standards, Classification Society Rules, Legislation) are used for assessing the design. Lloyd’s Register Naval Ship Rules not only provide details of standards to be adopted but also provide empirical relationships for assessing equipment and structural requirements for warships.

4.6.10

Arrangement Studies

1

During the Design Survey phase a number of preliminary arrangement studies may have been carried out to identify major arrangement drivers for inclusion in concept models and provide fixed points for partial validation of trends produced by concept models. As identified earlier the key drivers for a monohull warship are machinery configuration, upper deck area, ship length, aviation, tankage, stores and zoning. During this phase of the design further more detailed arrangement studies will be undertaken. The key studies to be undertaken are: •

Machinery options studies;

•

Accommodation and commissariat;

•

Aviation;

•

Topside layout;

•

Operational spaces;

•

Zoning studies & vulnerability;

•

Tank layout;

•

Stores layout & handling arrangements;

•

Structural arrangement.

Machinery Option Studies 2

The Machinery Option studies identify the most suitable machinery configuration to meet the speed, range, endurance and vulnerability performance requirements whilst minimising the through life cost of fuel, lubricating oil, etc. The Option Studies also define the high-level equipment requirements, spatial and volumetric requirements for the propulsion machinery and auxiliary equipment and include system diagrams, representative arrangement and equipment lists and uptake and downtake requirements.

3

The Machinery Option studies will also develop budgets for the electrical and fluid requirements for the combat system.

4

The Machinery Option studies rely heavily on the use of manufacturers supplied standard product data. The designer should be aware that this data is generic and may not accurately reflect the equipment that will actually be fitted to the vessel. The manufacturers data provided must be treated with caution and appropriate margins allocated. Accommodation Studies

5

Accommodation studies will take account of the number and ‘mix’ of the crew and officers, the standard of accommodation and the level of segregation between ranks and sexes. The relationship between compartments must also be considered; for example, between the sleeping and dining areas used by different groups within the ship’s company, or between stores, galley and servery areas. These relationships will then impact upon the design of access passageways, companionways and escape routes.

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In undertaking the Accommodation Option studies the requirements for zoning, firefighting and damage control should be taken in to account, as these will impact on the space required for HVAC, electrical power generation and domestic services, and the associated system routes. Aviation Studies

7

Aviation Studies should consider the types of aircraft that will be operated from the warship as this will drive the size and location of the flight deck as well as the hangar and other support arrangements. In addition to the characteristics defined in Section 3.2.5 the following should also be taken in to consideration: •

•

•

•

Location of machinery uptake and downtakes identified in the Machinery Options studies; The positions of aerials and antennas and other combat s ystem elements identified from the Topside Layout studies and the impact that these will have on the aircraft and its systems (or the effect that the aircraft will have on the aerials, antennae and other combat system elements); The position of AVCAT storage tanks and the associated pipework for fuelling or defuelling; The locations of the Air Weapons Magazines and associated stowage and arming routes and facilities;

•

Escape and evacuations routes;

•

Structural design requirements;

•

Firefighting requirements.

Stores & Magazines 8

At this stage of the design the requirements for the stores may not be clearly defined. The requirements for stores tend to be driven by crew complement and endurance (for victualling stores), maintenance regime and equipment availability targets. Thus the requirements, in terms of required volumes and deck areas for stores, their access and removal routes and handling systems, are likely to be based on the requirements for previous vessels.

9

It is also likely that the requirements for magazines are not clearly defined in terms of what ordnance and ammunition will be required and in what quantities. These will not be formalised and quantified until later in the design process. Again a number of assumptions, with respect to category of ordnance and the size and location of the magazines will have to be made based on the designer’s best understanding of the likely combat system fit, and appropriate margins allocated for weight and space. Operational Spaces

10

Again the requirements for operational spaces in terms of location, deck area, tween deck heights and inter-relationship with other spaces will not be clearly defined. The designer will, therefore, need to make a judgement as to the most suitable location for the operational spaces, based on previous experience and taking account of known changes to operating philosophy and equipment fit. Again suitable margins must be allowed to account for these uncertainties.

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Topside Layout 11

A detailed understanding of the physical interrelationships between the various combat system elements and the warship is paramount. The Topside Layout studies will address the following: •

Space requirements, including location, maintenance envelopes and removal routes;

•

Physical clearances and location for RADHAZ;

•

Weapon and sensor requirement for clear arcs;

•

Electronic separation for EMC;

•

Weight and location of all components as this drives the structural design and stability;

•

Demands on support services, including power, voltage, frequency, tolerances, etc.;

•

Chilled water supply; quality and quantity of waste heat;

•

Impact on Combat Management System;

•

Impact on aviation arrangements;

•

12

Impact on machinery selection and arrangement (including location and impact of uptakes and downtakes).

Again much of this information may not be readily available to the designer at this stage in the design and he must rely on Original Equipment Manufacturers (OEMs), design consultants and other domain experts to provide the n ecessary information. Structural Design

13

The structural design of a warship will invariably adopt the requirements of classification societies. Most classification societies now have standards for Naval Ship construction in addition to their rules for commercial ships. At this stage the structural design definition may be limited to: •

•

A midships section drawing (and possibly some additional sections in the fore and aft part of the vessel and in way of the flight deck and machinery spaces); A profile and decks drawings.

14

Note the clear tween deck heights should be checked to ensure that the depth of girders and transverse beams have not eroded clear deck heights.

4.6.11

General Arrangement

1

The results of these layout studies are then used to produce the general arrangement of the vessel. The general arrangement is the key configuration document by means of which all the above design studies are co-ordinated and managed. It is a key design tool as it allows a holistic view of the design, identifies conflicts and is one of the key outputs from the design development activity.

2

In addition, it also addresses requirements such as berthing, towing, sea boats and RAS operations.

4.6.12

Development Tools

1

There is a wide range of tools available to assist with the design development. In the early stage of the design, spreadsheets are widely used. In addition, there are specialist tools available to assist the designer with the spatial interrelationships. Such programmes include 2D and 3D CAD drafting/modelling packages and specialist warship layout tools.

2

To assist with the synthesis of the machinery configuration there are a number of specialist programmes available e.g. resistance and powering prediction, propeller design, Electrical Load Schedules.

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Outputs

1

The key output is an Indicative Design, which includes the following: •

General arrangement;

•

Machinery arrangement;

•

Preliminary topside arrangement;

•

High level system diagrams;

•

Major equipment lists;

•

Chapter 4

Outline performance specification used to inform the System Requirements document, including: •

Speeds;

•

Range;

•

Endurance;

•

Operability;

•

Ship motions;

•

Dimensions;

•

Installed powers;

•

List of design assumptions, margins and caveats;

•

Design Risks.

4.7

OUTLINE CAPABILITY DESIGN ASSESSMENT

4.7.1

Design Assessment Process

1

The design assessment process is the mechanism by which the output of the design development is monitored and assessed. The design assessment activities are undertaken concurrently with design development and are intimately li nked with the design development.

4.7.2

Objectives

1

While design development is the process by which the design is developed, the design assessment tasks are the means by which the design performance is compared against the required performance. The design assessment process is the ongoing and continuous review of the performance against the given standards or requirements.

4.7.3

Inputs & Drivers

1

The inputs to the design assessment process are the: •

Design performance developed from the design development;

•

Performance requirements extracted from: •

The URD including the W arship Characteristics;

•

The SRD;

•

Applicable Standards, Regulations and Legislation;

•

Key Integration Parameters.

4.7.4

Methods

1

There are many methods of assessing the performance of the design against the requirements. The method adopted will be determined by the criticality of the requirement, the stage in the design process, the maturity of the design and the procurement strategy (see 4.11 Acceptance).

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The performance can be assessed by self-checking by the engineer, peer reviews, formal assessment reports and formal Design Reviews using either an internal or external Review Chairman (See Section 3.5.1). Qualitative Assessment Against Existing Configuration

3

In its simplest form the design can be assessed against the arrangement of an existing vessel. If a given arrangement of equipment has proven reliable in-service and the new design has a similar arrangement, then the new design is also likely to be acceptable. This method of assessment is widely used where the acceptance criteria cannot readily be quantified numerically and accurately measured. It is also used early in the design process when quantitative information on the design or requirements is not readily available.

4

For example, the vulnerability of the main propulsion machinery configuration of a new design can readily be compared with that of an existing design and conclusions drawn on the performance of the new design based on t he existing design.

5

It can, however, only be used where the arrangement is similar to the existing arrangement. Where there is significant difference between them then there is scope for disagreement and conflict and alternative methods must be adopted. Qualitative Assessment Against a Given Standard

6

Where the requirement is more prescriptive and defined against a given standard (e.g. DefStans or Statutory Instruments) then the design can be assessed by comparing it against the given standard. This is the method used by classification societies and regulatory authorities to assess construction details and arrangements (e.g. where a connection or insulation detail is type tested by an approved authority).

7

However, again there is scope in the assessment for subjective interpretation of the requirements if the arrangements depart significantly from those that are familiar to the assessor. Further demonstration and justification (and perhaps also negotiation) wil l then be required. Quantitative Assessment Against a Given Standard

8

9

This is the method of design assessment preferred by most engineers as it gives an unambiguous result. The performance of most shipboard systems and equipment can be assessed quantitatively. Quantitative assessments can be undertaken for: •

Structural design;

•

Hydrodynamics;

•

Ship stability;

•

Sub-systems;

•

Mechanical equipment;

•

Electrical systems;

•

Vulnerability;

•

Signatures.

Quantitative assessments can be undertaken using calculation, model testing or physical measurement.

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4.7.5

Outputs

1

The outputs from the design assessment process, compares the performance of the design against the user requirements and highlights design risks, assumptions, margins and caveats. design assessment outputs are likely to include: •

Approved scantling drawings;

•

Hydrodynamic assessment report;

•

Model test reports;

•

Stability assessment reports;

•

Vulnerability assessment reports;

•

Signature assessment reports;

•

System and sub-system assessment reports.

2

The results of the design assessment process feed directly in to the progressive acceptance process.

4.8

SYSTEM DESIGN

4.8.1

Objectives

1

The overall aim is to show that a fully working system (warship) can be produced that will meet the capability requirements within the allocated budget without excessive risk: •

Inform the development of the SRD;

•

Generate an Indicative Design;

•

Develop the product breakdown structure;

•

Define the system and its component sub systems and demonstrate functionality;

•

Determine the physical elements i.e. materials and equipments, of each sub s ystem;

•

Ensure the functional and physical compatibility of all sub-systems;

•

Estimate the resources required to produce the system;

•

Estimate the costs of the entire system;

•

Estimate the timescales to produce the system;

•

Identify risks to achieving anticipated performance, cost a nd timescale.

4.8.2

Inputs

1

The inputs are performance targets for each system from the URD, the definition of a selected design point from the Design Survey and major system and sub-system parameters from the design development.

4.8.3

Methods

1

All the normal design processes for each discipline will be employed. Very often the start point will be a previous design. It is unusual for sub-system design to start from a clean sheet. Classification Society guidance will dictate configurations for many systems. However excessive reliance on past data can be dangerous when a novel element is introduced in to the design. What at first sight may seem a straightforward modification is not always the case. In many sub systems operation off design point or in transient conditions may become the major driver and will need investigation particularly when something different is added to an otherwise conventional design. More comprehensive analysis and simulation tools should then be employed. In extreme cases experimental installations or demonstrators may be needed. The methods discussed in Section 3.5.7and 3.5.8 can be used to improve the estimates of costs and effectiveness of the completed system.

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2

Risk assessment is often quite subjective and while brainstorming sessions, perhaps with non domain experts also involved, can be extremely useful in generating potential problems, alternative perspectives obtained from peer review by domain experts from outside the project should be used to moderate all assessments. If system design is being performed as part of a tender exercise then a compliance matrix against the current URD/SRD issue will be required.

4.8.4

Outputs

1

The outputs are based around an Indicative Design and cover: •

System Requirements Document (SRD);

•

Product breakdown structure;

•

General arrangement;

•

System parameters, diagrams, specification and capability statements;

•

Major equipment lists;

•

Estimated cost and outline build programme.

4.9

CONTRACT DESIGN

4.9.1

Objectives

1

The two objectives are: •

•

To generate an adequate design specification that can be signed up to contractually by, and entails an acceptable degree of risk to, both parties. It is the parties’ perception of risk that will determine the level of design definition in the contract; Fixed cost.

4.9.2

Inputs

1

The input required is the System design definition.

4.9.3

Methods

1

Generally an Invitation To Tender (ITT) will be developed based on the SRD and informed by any Indicative Design work already performed. The Indicative Design may well be provided as part of the tender package. In response a compliancy matrix against the current URD/SRD will be required.

2

The methods used will be similar to those used during the system design stage but taken to a greater level of detail in order to obtain the most accurate estimate possible of cost and timescale. Costs will be built up, from sub-system and equipment supplier quotes, in response to detailed technical specifications. In contrast to previous stages there will be much more work done on planning to ensure that delivery timescales can be met. By this stage the situation within facilities with regard to other projects will be much clearer and detailed facility production scheduling can be considered.

3

It must be recognised that greater level of definition in physical description does not necessarily mean greater confidence in promised performance. Proof of concept may be required in terms of prototype systems or demonstrators. Extensive analysis may be required to demonstrate that the system and sub-system definitions can provide the quoted level of performance. Risk cannot necessarily be transferred simply by means of a statement in a contract. If the supplier does not deliver the promised performance, whilst he may be liable for the value of the contract, the customer will still have the problem of maintaining his obsolete kit and finding another solution. The customer may, therefore, wish to conduct his own analyses etc. to determine the ability of the supplier’s proposed design to meet t he contractual performance.

4

A key element of the contract will be specification of the means and criteria by which acceptance will be achieved. See Section 4.12.

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5

It must be accepted that no design is perfect and can always be improved as more is understood. Therefore, an important element of the contract will be the arrangements for dealing with how subsequent design changes are to be managed and paid for. Either the customer or the supplier will initiate changes but one thing is absolutely certain; they will happen!

4.9.4

Contracting Implications

1

The impact of the contracting strategy on the warship design and construction is often overlooked and can significantly increase project risk if not properly managed. It is now common for the prime contractor to be either a joint venture company or industrial alliance. The design and construction tasks are usually split between the partners, based on an agreed work share defined in the contract. Care must be taken to ensure that tasks are allocated to the companies best qualified to undertake the work.

2

There is also a trend towards sub-contracting larger packages of work to OEMs. For example, the design and manufacture of the whole propulsion and generation train may be sub-contracted to a single supplier. The philosophy behind this approach is to reduce the number of contractual interfaces and hence reduce the integration risk and pass this risk to the OEM. The prime contractor, however, loses direct control of the risk and has to rely more heavily on the OEM. The warship designer must be confident in the OEM’s ability to design and fully integrate the systems for which they are responsible before a contract is placed, and must be involved in all contract technical negotiations with OEMs.

3

It is incumbent on the Design Manager to ensure that purchase orders for equipment are placed in a timely manner in order to ensure the delivery of design and interface information to meet the design programme. The warship designer must also ensure that design information is passed back to the project in a timely manner and ensure the accuracy and fidelity of the information. All requirements for the delivery of design and integration information should be included in the Purchase Order and contractual penalties imposed on sub-contractors for failure to deliver the required information to meet the programme needs. These requirements should include a delivery schedule and limits on the accuracy and fidelity of the design information to be delivered.

4

The Design Manager is also responsible for co-ordinating all the design information from the sub contractors and for the design integration of the equipment into the ship. In undertaking this activity the Design Manager should consider the installation sequencing and other integration activities.

4.9.5

Outputs

1


Performance specification;

•

System specification;

•

Sub system specifications;

•

Equipment specifications;

•

Material specifications;

•

Standards;

•

Acceptance criteria and methods;

•

Costs;

•

Build Programme;

•

Delivery date.

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4.10

PRODUCTION DESIGN

4.10.1

Objective & Drivers

1

The objective is to generate the design definition necessary for the efficient and effective manufacture of the warship to meet the contract requirements (URD, SRD and Shipbuilding Specification), Test Evaluation and A cceptance Plan(s), schedule and cost constraints.

4.10.2

Inputs

1

The input for the Production Design is the Contractual Design Definition, which includes the Shipbuilding Specification, the Indicative Design, the System Requirements Document and the Test Evaluation and Acceptance Plan(s).

4.10.3

Methods & Tasks

1

The methods used will be similar to those used during the contract design stage but taken to a level of detail necessary to develop the production guidance information. The latter will then be used by the production department to build and commission the ship. The principal focus of the production design will be on producing detailed manufacturing information and providing design disclosure and justification documentation; thus further de-risking the design. Detailed production design uses a combination of engineering experience and judgement, empirical calculations, statistical analysis, computer aided design and physical model testing. Production design tasks include: •

•

•

Detailed development, optimisation and assessment of hullform, hydrodynamics and powering; Production of lofting information and computer aided manufacture (CAM) data; Structural design and preparation of arrangements and details of units, blocks and modules;

•

Production of detailed technical specifications for materials & equipment ordering;

•

Preparation of detailed construction drawings;

•

Detailing of system and sub-system arrangement of all ship systems and components;

•

•

•

Preparation of supporting design documentation, including safety justification and substantiation; Detailing maintenance and operating i nformation; Preparation of information;

detailed

interface

specifications,

interconnection

diagrams

•

Design of seating and mounting arrangements for all equipment;

•

Liasing with sub-contractors and OEMs and co-ordination of design inputs;

•

Design change management;

•

Demonstration of performance through calculations, model testing, etc;

•

Design configuration and control.

and

4.10.4

Tools

1

The principal tools used to manage the production design are the Computer Aided Design (CAD) system, the Integrated Product Data Management (IPDM) system and Integrated Product Data Environment (IPDE).

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Outputs

1

The outputs from the Production Design are as follows:

Chapter 4

•

Optimised hullform, hydrodynamics and powering and associated assessment reports;

•

CAM and lofting information for production;

•

Structural arrangements and details of units, blocks and modules;

•

Detailed technical specifications for materials, s ystems and equipment ordering;

•

Detailed construction drawings;

•

System and sub-system arrangements of all ship s ystems and components;

•

Design documentation, including safety justification and substantiation;

•

Maintenance and operating information;

•

Interface specifications, interconnection diagrams and inf ormation;

•

Seating and mounting arrangements for all equipment;

•

Detailed acceptance criteria and methods.

4.10.6

Construction Implications

1

The construction method adopted for a warship is driven by the construction facilities and industrial infrastructure available to the project. In most cases, the warship production process will be driven by shipyard facilities. Most UK shipyard facilities have limitations on their production facilities and this in turn places limitations on the size and capability of vessel that can be built, launched and outfitted.

2

Where the proposed warship is likely to exceed the existing shipyard capacity (e.g. a large conventional aircraft carrier) then the construction philosophy must be specially considered.

3

The warship design philosophy must support the construction philosophy. The warship designer must, therefore, have a good understanding of where and how the ship will be manufactured. He must engage with ship production engineers as early as possible in the design process to ensure that the design proposed takes full account of any constraints placed on the design by the available construction facilities.

4

Each design decision and the associated assumptions will impact on the construction of the ship. Early involvement of the production engineering specialists is necessary to ensure that the warship design can be manufactured in a cost-effective manner. This will reduce the risk of costly changes to the design during the production phase as a result of production li mitations that were not addressed during the appropriate design phase.

5

In developing the design due regard should be taken of the tolerances inherent in the production process. Production engineering specialists should be involved throughout the production design to ensure that the production design meets the needs to the production department.

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4.10.7

Structural Design

1

In producing the structural design philosophy due regard should be taken of the cost implications. The structural style to be adopted will be governed by both performance and “producibility” factors. Most production facilities are optimised for particular methods of manufacture and conflicts will have considerable cost implications. It may be more cost effective to limit design choice to easily produced configurations. The structural configuration is influenced by: •

•

•

•

The maximum size of frames will be constrained by the frame bending equipment at the yard. Where beam sizes exceed the capability of the frame bender then sections will need to be cut and built up from flat bar. This significantly increases material and labour production costs due to increased preparation and welding costs; The maximum and minimum plate thicknesses are determined by the available weld procedures and whether automatic or manual welding is adopted; The maximum dimensions and thickness of double curvature plates is limited by the capacity of presses. Where this is exceeded, then double curvature plates are formed on jigs using manual heat bending methods that are very labour intensive. Double curvature plating should be minimised; Access for double-sided welding. possible.

Single-sided welding should be avoided where

2

A lightweight orthogonal grillage, with thin plating and closely spaced stiffeners, typical of older warships is a factor affecting the fabrication costs. A typical lightweight grillage structure leads to a complexity with a large amount of welding and slotting, which in turn leads to higher costs. In addition, the use of lightweight plate and closely spaced stiffeners will result in weld distortion and subsequently results in a greater amount of rework.

3

Traditional commercial vessels tend to adopt longitudinal framing supported on large transverses or transverse framing supported on longitudinal girders. This facilitates the use of automatic welding processes. The plating thickness for commercial ships will also be thicker, with less welding and hence less weld distortion.

4

A ‘rule of thumb’ suggests that the steel work production effort (man hours per tonne) is inversely proportional to the square of the weight i.e. if the weight is halved the man hours per tonne is quadrupled.

4.10.8

Use of Equipment Manufacturers’ Design Information

1

A concurrent engineering approach is often adopted to allow production to commence before the production design work is fully complete. Concurrent engineering should reduce the overall build programme and allow the shipyard to maintain high utilisation in both the design and production departments.

2

However, it is not without its risks. Care must be taken to ensure that construction only commences once the design in way of the area of construction has been finalised, full details of the equipment to be fitted has been received and the accuracy of the information has been 24 verified and endorsed by the project.

3

It is, therefore, incumbent on the Design Manager to ensure that all design information is available in a timely manner and at the appropriate quality. The Design Manager is responsible for co-ordinating all of the design information from the sub-contractors and its integration into the ship. In undertaking this integration the Design Manager also needs to consider the sequencing of the installation and integration activities.

24

Where the warship design is based on information received from the suppliers, the design and installation tolerances and interface specifications of the equipment should be carefully scrutinised and understood such that the impact of these tolerances can be incorporated in to the production design and the construction programme. ___________________________________________________________________________________________________________

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4.10.9

Contracting Implications

1

The impact of the contracting strategy can significantly increase project risk if not properly managed. It is now common for the prime contractor to be either a joint venture company or industrial alliance. The design and construction tasks are often split between the partners, based on an agreed work share defined in the contract. Care must be taken to ensure that tasks are allocated to the companies best qualified to undertake the work.

2

There is also a trend towards sub-contracting larger packages of work to OEMs. The philosophy behind this approach is to reduce the number of contractual interfaces and hence reduce the integration risk and pass this risk to the OEM. The prime contractor, however, loses direct control of the risk and is dependent upon the OEM.

4.10.10

Production Engineering

1

Once the warship designer has produced the outline structural design, general arrangement and detailed system arrangements it will be passed to the production engineering specialists who will commence work on defining the construction process sequence and programme. The production engineers will also assist with preparing material and production labour estimates. Planning

2

The first stage of the production planning process is to break the ship structure into panels, units, blocks and modules and define the construction sequence of these panels, units and modules.

3

The structural fabrication sequence can be simplistically defined as follows: •

•

•

•

4

These panels are welded together to form ‘units’ or ‘blocks’ within the fabrication shed (a block may be one or more units welded together); A number of units or blocks will then be welded together and equipment, pipework, cabling and other outfit installed to form a module; These modules are then transferred to the building berth where they are connected together and all system piping, cabling and other services interconnected.

The maximum size and weight of these panels, units, blocks and modules will be determined by the production facilities available; in particular: •

•

•

5

Flat plates are first cut and welded together into panels; stiffeners are then welded to these panels;

The maximum size of plate panels is constrained by the panel line; The maximum size of units or blocks is driven by craneage for lifting and turning within fabrication halls; The maximum size of modules and the level of outfit is driven by site and berth access constraints, transportation, lifting and craneage on the building berth/dock.

The size of the units and modules, and the positions of the connections, are also governed by: •

The positions of equipment and relationships with major compartments/system routes relative to the breaks;

•

The overall layout of structure, spaces and equipment;

•

Erection sequences and consequent effects on access for equipment installation;

•

Access restrictions to within the unit or module (i.e. top, bottom, ends or sides).

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The sequence in which the units or modules are fabricated and installed is principally driven by: •

The availability and reliability of design information;

•

Delivery schedules for equipment with long l ead times;

•

Access and installation requirements for equipment;

•

The level of pre-outfitting of modules before erection.

4.11

PRODUCTION

4.11.1

Construction

1

Construction usually commences on areas which are least influenced by long lead time equipment. Usually construction commences in double bottom tanks under stores or accommodation spaces in the midships region and then progresses to machinery spaces as the information on the machinery arrangement and equipment is developed.

2

The development of the production design continues throughout the production phase and the designer must interact closely with the production departments to ensure that the vessel is built in accordance with the design. The designer must ensure that: •

The vessel is produced in accordance with the design documentation;

•

That departures from design do not impact on performance;

•

•

Acceptance of production against design can be achieved and any concessions identified, assessed and agreed; Any production problems or changes are fed back to the designer, so that their impact can be assessed and the design updated to take account of these changes.

4.11.2

Monitoring Production

1

During production, it is important to measure progress. There are two principal means by which production progress is monitored; by overseers from Classification Societies, statutory bodies or the MoD to confirm compliance with standards, regulations or the contract, and by application of the shipbuilder’s quality systems. The role of MoD Naval Authorities and Classification Societies (as Recognised Organisations) is described in 2.9.3 and the standards that are applicable are discussed in 3.4. The following paragraphs describe a typical shipbuilder’s quality system (the actual system adopted may be slightly different).

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Chapter 4

The shipbuilder’s quality system is based on the development and application of Test Forms, Initial Compartment Inspections and Final Inspections. Final Inspections are the final element of production acceptance and are, therefore, covered in the following Section 4.12. Each of these elements may be measured by quantifying and detailing the number of production, setting to work, commissioning, and inspection events. To facilitate this, it is appropriate to define and monitor a number of metrics: •

•

•

•

•

Test Forms. Test Forms capture system setting to work and commissioning. Their writing should be well underway during the design of the systems and complete and captured in the ship build programme prior to production commencing (although this an ideal and the programme will likely evolve as production progresses); Compartment Layouts. Metrics for the number of Compartment Layouts to be accepted by shipbuilder and the MoD IPT should have been monitored through the ship design and the remaining outstanding ones managed closely. Similarly metrics for the number of systems integrated into the design should have been monitored and the remaining outstanding ones managed closely; Production and Engineering - Metrics for manufacture cover the production of pipes and vent spools, and installation of pipes, vent spools, length of main run cable reeved and terminations completed. Metrics for system commissioning cover pressure and endurance testing of pipe and vent test paths, line checking of electrical test paths and incrementally setting to work systems. Inspections of outfitted compartments should be undertaken only once compartments have been complete and Final Inspection following final clean and paint should be aft er all systems have been set to work, with handover to ship staff after all defects have been cleared; Combat System - Metrics for combat system compartments and equipments need to follow the well practised route of compartment gradings, equipment installation, Installation Inspection, Set To Work, Equipment HAT, Group Trials and finally Naval Weapon Harbour Trial followed by Sea Trials; Whole Ship Acceptance - Metrics for whole ship acceptance can be produced for achieving contracted performance against the atomised contract specification.

4.12

ACCEPTANCE

1

The purpose of the acceptance process is to provide evidence that the capability requirement defined in the User Requirement Document (URD) and System Requirements Document (SRD) has been delivered. To achieve this successfully, the acceptance process shall also provide assurance that the operation of the vessel can be accomplished safely and successfully. The acceptance process is also to provide assurance of the acceptability of those aspects of the design that cannot be clearly demonstrated through trials and tests (such as safety, operability, supportability and survivability). For a warship, the acceptance process will typically include the following steps:

2

•

Develop Acceptance Strategy;

•

Develop Test Evaluation and Acceptance Plans (this is a staged and iterative process);

•

Undertake tests, trials and acceptance activities in accordance with the plans;

•

Collate and evaluate trials and acceptance evidence for the warship;

•

Offer the warship to Procurement Authority for Acceptance off Contract (AoC);

•

Undertake further operational trials;

•

Collate and evaluate evidence for overall S ystem Acceptance (SA);

•

Offer to the user for System Acceptance;

•

Undertake Fleet Date Inspection (FDI) prior to In-Service Date (ISD).

The overall acceptance process for a warship is illustrated in Figure 2.3 and a typical outline acceptance route map in Figure 4.3 .

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Chapter 4

The acceptance process will be applied to the requirements laid out in the User Requirement Document (URD), the System Requirement Document (SRD), the Shipbuilding Specification and Indicative Design. The main components identified in these documents can be considered to include the following: •

The vessel;

•

The communications outfit (including cryptographic equipment);

•

The weapon systems and provision for fit ting self protection weapons;

•

Air, surface and underwater surveillance;

•

Aviation systems;

•

Training as identified and agreed through a Training Needs Analysis;

•

The required availability through the support infrastructure and service.

4.12.2

Roles and Responsibilities

1

The overall Acceptance Authority for the systems, including the warship and other LoDs is the user. The user has final responsibility for ensuring that the warship, along with its systems, is fit for purpose and that the vessel is properly manned with trained crew. He is also responsible for ensuring that facilities are in place for the effective maintenance and support of the warship inservice.

2

The Procurement Authority is responsible for ensuring that the warship meets the requirements of the SRD, Indicative Design and the Shipbuilding Specification, as defined in the procurement contract. The Procurement Authority is also responsible for developing the Test Evaluation and Acceptance Plans, which will allow the user to confirm that his requirements have been met. He will then offer up the warship to t he user for System Acceptance.

3

The contractor is responsible for developing the design, manufacturing the warship and demonstrating that the warship meets the requirements of the SRD, Indicative Design and the Shipbuilding Specification, as defined in the procurement contract. The contractor will undertake the tests, trials and acceptance events under the supervision of the Procurement Authority’s nominated representative. The contractor is then responsible for collating all of the contractual acceptance evidence and presenting it to the Procurement Authority.

4.12.3

Acceptance Strategy

1

The acceptance strategy should be developed as early as practicable in the product lifecycle, in parallel with the User Requirement Document. The acceptance strategy is then used to assist in the development of an Integrated Test, Evaluation and Acceptance (ITEA) Plan.

2

Although the strategy should be stable it should be periodically reviewed and refined to reflect the progressive down-selection to a single solution, up until the point that the development/manufacture contract negotiations are finalised. The strategy should thereafter be kept under review throughout the operational life of the equipment/system.

3

Where incremental acquisition is adopted then both the capability increments and timing of those increments must also be considered. The acceptance strategy should include a concise, explicit definition of what the system acceptance event is (or are) to be in terms of what equipment capability and when it is required to be available for the start of validation, or operational use.

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The strategy should also address any issues that need to influence the URD, SRD, and ITEA Plan, such as: •

•

•

•

•

•

•

•

•

•

5

Chapter 4

The relative significance and importance of each of the LoDs, how interdependent or independent they are, and how these issues will impact ITEA arrangements and the related allocation of responsibilities between the Procurement Authority and the user; Interdependencies with other capabilities and/or acquisitions, including interoperability, and how those interdependencies will be managed; The extent to which the contractor is expected/required/can be responsible for the generation of acceptance evidence, or where independent agencies or t he MoD must be involved in the generation and/or scrutiny of evidence; Who will be responsible for post-manufacture installation, integration, and associated testing; How any associated ‘systems-of-systems’ testing and acceptance will be managed; How MoD test & evaluation policy will apply (e.g. use of MoD ranges, test & research facilities, simulation etc.); Capability/cost/time priorities and risks - the scope for resorting to Limited System Acceptance and Provisos in mitigation of risks; Significant technical issues such as a need for design certification, or the accepting of COTS items; The need for underpinning and enabling information management strategies; To what extent each of the non-equipment LoD will need to be individually verified as a precursor to collective validation;

The Strategy should also address significant management issues such as: •

Who the Acceptance Authority is (see above);

•

Who the champion for each LoD is;

•

The roles and responsibilities of k ey stakeholders;

•

The organisation of the stakeholders within formal groups;

•

How risk management will be applied as an aid to engineering the ITEA Plan.

6

The Strategy (and the ITEA Plan) should draw from and contribute to the Master Data & Assumptions List wherever possible and necessary, as ITEA activity is a significant contribution to project lead time and cost.

4.12.4

Integrated, Test, Evaluation and Acceptance Planning

1

ITEA planning is a through-life activity requiring a through-life perspective at every stage in the product lifecycle. Planning should commence during the development of the System Requirements Document, as soon as the task of defining Validation and Verification (V&V) criteria has started within the requirement engineering process. The ITEA should then be updated and refined on an ongoing basis throughout the procurement process to reflect the increasing maturity of the design solution.

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Chapter 4

The ITEA Plan should: •

Identify all the major stakeholders, across all Lines of Development;

•

Embrace all of the options being presented;

•

Be consistent with the proposed procurement strategy;

•

Be adequate to support the whole lif e costing and schedule estimates;

•

Be tailored to the ship type and range of technologies selected;

•

Identify major risks, cost and schedule drivers;

•

Identify sources of existing evidence that can be re-used;

•

•

•

Identify any other extant sources of relevant evidence such as the on-going research programme; Identify major demands on test resources; Define Verification and Validation criteria with links to the SRD and Shipbuilding Specification;

•

Define Test & Evaluation activity to be performed at each stage of the project;

•

Identify interoperability testing issues.

3

By the time the URD and SRD are baselined prior to contractor selection, the scope of the ITEA Plan should be complete and tailored to the selected options and technologies. The content should be as fully defined as is possible. It should be noted that it is imperative that the ITEA Plan is base-lined and agreed with all key stakeholders before negotiations with the selected contractor are concluded, and the contract is signed and other tasking arrangements are invoked. Otherwise, the contract is liable to suffer from “requirements creep”, with its subsequent impact on cost and programme.

4

Once the contract is placed with the contractor, the contractor will be responsible for developing and maturing the design and building the vessel in accordance with the design. Any changes to the Indicative Design arising through the detailed design phase will be addressed and agreed between the prime contractor and procurement authority as appropriate. The way in which these will be addressed will be defined in the contract. The ITEA Plan will, therefore, need to be continually updated to reflect the design development.

4.12.5

Certification Planning

1

The acceptance process involves a number of stakeholders and organisations within the MoD. Notably Key Hazard area certification involves the ongoing and independent review of the emerging design by domain experts within the N aval Authorities.

2

To facilitate the Key Hazard area certification process for warships, a plan needs to be drawn up by the project and key certification activities and milestones agreed with the relevant stakeholders. The key certification activities are closely linked to the Maritime System Maturity Level Reviews and formal Design Reviews and the Certification Plan may form part of the ITEA Plan. This Certification Plan needs to be updated on a regular basis throughout the life of the project to reflect any changes to the programme or changes to l egislation.

3

Where commercial standards are adopted, acceptance of the commercial standards will be on the basis of certification against the specified Classification Society notation (or equivalent), and acceptance of the Safety Case, demonstrating that the hazards to all personnel operating or embarked in the vessel are As Low As Reasonably Practicable (ALARP).

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4.12.6

Verification and Validation Criteria

1

Verification and validation is against the itemised user or system requirements. It is the reference point against which the solution will be tested to give the user confidence that the requirement is satisfied. The satisfaction of each and every individual candidate user requirement must be able to be validated. The satisfaction of each and every individual candidate system requirement must be verifiable. To re-iterate: •

Validation criteria address measures of effectiveness;

•

Verification criteria address equipment capability and measures of performance.

2

The means by which the system or equipment is validated is expressed in the URD as a 'Validation Criterion' and/or in the SRD as a 'Verification Criterion', linked one-to-one with each atomised requirement. It defines the means by which achievement of the requirement will be demonstrated. By implication it indicates the 'severity' of the test to be applied to the solution, and thereby the level of confidence that the user needs in the test result. Each criterion should only be descriptive of a class of test method, so as to allow scope for optimisation of test arrangements later whilst engineering the ITEA Plan.

3

Defining V&V requirements is an integral part of requirements engineering. The validation criteria definition task is best started as soon as: •

The structure of the URD is established;

•

Initial population with user r equirements is completed;

•

Candidate solution concept classes are identified.

4

Early identification of validation requirements is necessary to inform long term planning of military exercises and range utilisation.

5

Early identification of verification requirements is necessary to enable timely identification of requirements for test articles and test facilities, and to inform whole life costing and scheduling, and contract negotiation.

4.12.7

Inspection Tests and Trials for Progressive Acceptance

1

To enable the above, each and every user and system requirement must be expressed explicitly as a 'testable' characteristic. Inspections, tests and trials are then developed to demonstrate that the warship, its systems and equipment meet the requirements.

2

For a warship project, the possibility of test failure is more often than not the biggest collective risk faced by the project as it matures from theory to reality. The testing and acceptance traditionally occur late in the procurement process, when most of the budget and programme contingencies have been used/ absorbed. Retaining adequate budget and schedule contingencies to absorb remedial action during trials and acceptance have merit. However, they may delay acceptance if they are not needed because, though it is easy for a programme to slip, it is notoriously difficult to a ccelerate a programme that is progressing better than planned.

3

Progressive testing and acceptance is the most common mitigation method used for warship projects. Acceptance will be the result of progressive disclosure and audit of the design and support procedures as they are developed. This incremental acceptance process is to be supported through Tests, Trials and Inspections (TTI) wherever appropriate, to confirm that the required equipment design features and performance have been provided and that the sustainability infrastructure/processes/procedures are both in place and demonstrably effective.

4

It is also of benefit to the procurement organisation to obtain buy-in from the stakeholders used on the design development.

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Chapter 4

For a warship project the progressive acceptance process will comprise of the following main elements: •

•

•

•

Model testing performance);

(e.g. resistance, propulsion and seakeeping tests to verify hullform

Simulation (e.g. support infrastructure modelling to demonstrate the support solution); Equipment selection (e.g. review against specified performance requirements and using reviewer’s previous experience of similar equipment); Plan approval (e.g. review of proposed arrangements and details to ensure user’s operational experience and aspirations are i ncorporated);

•

Document approval (e.g. review of operating and training manuals);

•

Safety Case and Key Hazard certification;

•

Factory Acceptance Tests (of key equipment);

•

Setting to Work (of systems and equipment);

•

Compartment and Lineout Inspections (possibly using CAD walk-through techniques);

•

Harbour Acceptance Trials (HATs);

•

Basin Trials (e.g. basic propulsion and steering);

•

Sea Acceptance Trials (SATs);

•

Final Acceptance Inspections (to ensure that all defects from previous inspections and trials have been corrected).

6

Acceptance off Contract will be achieved through collation and evaluation of the results from the above activities and presentation of these results to the procurement authority or his specialist representatives for acceptance.

7

Acceptance of the combat systems elements will also include demonstration of the integration at a shore-side Integration Facility, which will occur prior to installation of equipment and systems on board the ship.

8

After Acceptance off Contract it will be the Procurement Authority’s responsibility to manage the remainder of the acceptance activities up until System Acceptance. During this period the procurement authority will be responsible for operating and maintaining the vessel and demonstrating to the user that the overall system meets the user’s requirement. Trials undertaken during this period normally include interfacing and operations with other assets, warships and platforms. For example, trials may include First of Class aviation trials, replenishment at sea trials and weapons testing and trials, where these have not been included in the shipbuilding contract or where they have been provided to the contractor as Government Furnished Equipment (GFE).

Design and Build

SA

AoC

ISD/IOC FDI

STW

CST

SARC 2 HAT

Fast Cruise

BTs

SARC 1

SARC Recovery Period

SARC 2

5

Staff Sea Check

SARC

6

Final Inspection

SARC 4

SARC 3 5 BOST 6 2-4 weeks

SSMOB Assume duties for care and protection

SUPPLIER LEAD RESPONSIBILITY

Preliminary Sea Training

PROJECT PROGRAMMING AUTHORITY

Fleet Programme

FLEET PROGRAMMING AUTHORITY

Figure 4.3 Typical Outline Acceptance Route map – Standard RN Training Requirements Prior To ISD ___________________________________________________________________________________________________________

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Chapter 4

4.13

IN-SERVICE

1

The management of the design does not stop after the ship enters service. The Design Manager will have ongoing responsibility for addressing design defects throughout the guarantee period. The responsibility for managing the design through life then progressively passes from the procurement authority to the In-Service Design Authority. This transfer may not occur on acceptance of the first vessel. The timing of this transfer will be dependent on the number of factors including the number of ships in the batch, maturity of the design, the number of ongoing enhancements to follow on ships in the batch and the readiness of the In-Service Design Authority to take on the responsibility.

4.13.2

Objectives & Drivers

1

The In-Service Design Authority responsibilities cover two main areas:

2

•

Maintaining the current capability;

•

Managing any capability upgrades.

Maintaining the current capability includes: •

Maintenance of availability;

•

Minimisation of running costs;

•

Managing safety and fitness for purpose;

•

Managing obsolescence;

•

Ensuring that the vessels are operated in accordance with the design intent;

•

Ensuring that the vessels are maintained in accordance with the design intent.

4.13.3

Inputs

1

To ensure that the vessel is operated and maintained in accordance with the design intent, the In-Service Design Authority requires a full disclosure of the final as-built design, i ncluding: •

Details of all design and build standards, non-compliances and concessions;

•

Detailed maintenance instructions;

•

Detailed ship specific operating instructions (standard ship operating procedures are the responsibility of the operating authority).

2

The input for any capability upgrade is the identified requirements that define the capability gap to be filled, any limitations of existing legacy equipment and applicable standards and l egislation.

4.13.4

Tasks

1

The In-Service Design Authority will review any reductions in capability that occur in-service through degradation of equipment performance, breakage, operational defects and deficiencies (OPDEFs), etc., to establish whether design intent has been compromised. If the design intent has been compromised then the In-Service Design Authority will be responsible for either: •

•

Producing revised performance envelopes, operating instructions and maintenance schedules; Proposing and implementing solutions to meet the original design intent.

2

The In-Service Design Authority will also ensure that the maintenance schedules are complied with and will be responsible for organising, specifying and overall management of all maintenance activities. The responsibility for undertaking the maintenance rests with the Maintenance Authority.

3

As equipment becomes obsolete then the In-Service Design Authority will manage the replacement or produce revised performance envelopes, operating instructions and maintenance schedules.

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5

Through the life of the ship there will be an ongoing requirement to upgrade and enhance the capability of the warship. Each upgrade project has a product lifecycle and includes design, procurement, manufacture, installation, acceptance and testing phases. The In-Service Design Authority will be responsible for the warship aspects of: •

Management;

•

Supervision;

•

Carrying out necessary design work;

•

Approval/authorisation;

•

Managing the design configuration of the vessels.

The In-Service Design Authority’s principle role is to ensure that the vessels are operated and maintained in accordance with the design intent in order to assure the safety of the ship and its crew, including: •

•

6

Chapter 4

Assigning warship safety levels (including mandating use of specific relevant legislation, statutory instruments and specific customer requirements); Managing warship safety assurance, including associated personnel and environmental issues associated with the operation of t he warship.

Specific safety tasks include: •

Monitoring weight growth;

•

Checking stability by regular inclining experiments;

•

Structural monitoring and surveys;

•

Survey and inspection of safety related equipment.

4.13.5

Outputs

1

The outputs from the In-Service Design Authority tasks are the provision of a defined capability with an agreed availability to the end user in a safe and costs effective manner. In providing the service the following documentation will be included: •

Safety certification;

•

Safety Case reports;

•

Maintenance management documentation;

•

Contractor logistic support guidance;

•

Operational guidance;

•

Contractual sub-system procurement specifications;

•

Production drawings;

•

Updated ship configuration baselines.

4.14

ASSESSING WARSHIP PROJECT MATURITY

4.14.1

Overview

1

In order to assess the maturity of a warship project from concept to acceptance and then in to service, it is recommended that a systematic framework of key integration parameters is established which covers performance, safety, management and commercial issues. Once the key issues have been exposed, it is then possible to determine the level of maturity of that project using a scale of maritime system maturity. By using such a framework, it will be possible to highlight aspects requiring attention and to provide robust assurance to management on the state of the project.

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project 4.14.2

Chapter 4

Maritime System Maturity Levels Project at Level 4 User Requirements

User

Procurement Agency

System Requirements / Contract

1

Integration, Verification, Testing

Sub-System Design, Component Requirements, Component Design

System and and Component Suppliers

4.14.3

Contract Acceptance

Platform/System Design & Sub-System Requirements

Warship Contractor

Maritime System System Maturity Maturity

Service Acceptance

2

3

4

Integration, Verification, Testing

5

6

7

8

9

Figure 4.4 Assessing Maritime System Maturity 1

The environment in which Maritime System Maturity Levels (MSML) are defined and are to be used can be explained in traditional system engineering terms, as shown conceptually in the “V diagram”, Figure 4.4.

2

As a project progresses from left to right, the level of design maturity increases from concept design through detailed design, in to acceptance events and finally in to service. The nature of ship projects is such that the various phases overlap so that at any one time, the project will be undertaking a number of activities in parallel, i.e. concurrent engineering. These may range from refining high level requirements through to detailed design of equipment and build. The maritime system maturity levels may be developed for each project. However, the following are recommended as a sound basis that reflects the stages of acquisition: •

Level 1 Needs Analysis/Concept Exploration/Key Requirements Identified;

•

Level 2 Concept Definition/Feasibility Design;

•

Level 3 Overall Ship Design;

•

Level 4 Ship Systems Design;

•

Level 5 Detailed Design Integration;

•

Level 6 Ship Test and Acceptance Detailed Planning;

•

Level 7 Ship Assembly/ Outfit/Test;

•

Level 8 Post Launch Outfit, Tests and Trials;

•

Level 9 Acceptance Sea Trials.

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project 3

Chapter 4

To capture the overall level of maturity for the whole ship, therefore, requires the assessment of maturity of all these parallel activities for each Key Integration Parameter. The example in the figure shows a project with an overall maritime maturity level of 4. At this stage, the project may be refining the User Requirement Document, refining the System Requirements Document and contract, maturing the warship design and conducting detailed design at the sub-system level. A more detailed figure showing the definition of the maritime system maturity levels, and the linkage with system engineering activities is shown in Figure 4.5.

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Systems Engineering Stage System Engineering Maturity Level when work complete Activities & Outputs at each System Level

Requirements Formulation – Concept Development 1 2 Needs Concept Analysis / Definition/ Concept Feasibility Exploration / Design Key Reqts Identified

Chapter 4

Engineering Development (Design & Construction/Trials Planning) 3 4 5 Overall Ship Ship Systems Detailed Design Design Design Integration (Engineering (Engineering (Engineering Design 1) Design 2) Design 3)

Construction & Trials 6 Ship/SM Test & Acceptance Detailed Planning

7 Ship/SM Assembly/ Outfit/Test

8 Post Launch Outfit, Tests and Trials

URD

9 Acceptance Sea Trials

Acceptance

System (Requirement, Design, Construction, Validation)

SRD

System Trials

System Design

SubSystem (Requirement, Design, Validation)

SubSystem Requirements

SubSystem Testing

SubSystem Design

Equipment (Requirements, Development, Procurement)

Equipment Requirement / Specifications

Development Item Equipment

Long Lead Orders

Initial Gate Key:

Low activity High activity

FATs Installation Tests

Equipment Procurement Main Gate

For each SML, define progress required against Key I ntegration Parameters: Naval Architecture, Marine Engineering, Information Management, Combat System Engineering, Whole Ship Issues, Maritime Interoperability, Safety, People, R&M, ILS

Figure 4.5 Defining Maritime System Maturity Levels

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Chapter 4

4

It is important to note that maritime system maturity level definitions also capture the setting of acceptance criteria at an early stage i.e. as the project progresses down the left-hand side of the “V-diagram”. This is an important aspect that ensures that the necessary preparations for acceptance are in place.

4.14.4

Key Integration Parameters

1

To facilitate reviews of project maturity, maritime system maturity may be assessed individually for various subjects or Key Integration Parameters (KIP). These subjects and their scope are shown below: •

Naval Architecture - Naval Architecture is sub-divided in to the following for convenience: •

•

•

•

Warship Arrangement: routes; Weights Estimation: weight;

This covers the arrangement of spaces and access This covers the estimation and management of ship

Margins: These include all margins associated with naval architecture, namely weight, space and centre of gravity assigned b y the MoD and by the contractor; Structure: This covers the derivation of loads and the design against an agreed standard, the subsequent build and survey, and operator guidance. This is


Chapter 4

4

It is important to note that maritime system maturity level definitions also capture the setting of acceptance criteria at an early stage i.e. as the project progresses down the left-hand side of the “V-diagram”. This is an important aspect that ensures that the necessary preparations for acceptance are in place.

4.14.4

Key Integration Parameters

1

To facilitate reviews of project maturity, maritime system maturity may be assessed individually for various subjects or Key Integration Parameters (KIP). These subjects and their scope are shown below: •

Naval Architecture - Naval Architecture is sub-divided in to the following for convenience: •

•

•

•

•

•

•

•

•

•

•

•

•

Warship Arrangement: routes; Weights Estimation: weight;

This covers the arrangement of spaces and access This covers the estimation and management of ship

Margins: These include all margins associated with naval architecture, namely weight, space and centre of gravity assigned b y the MoD and by the contractor; Structure: This covers the derivation of loads and the design against an agreed standard, the subsequent build and survey, and operator guidance. This is subject to Naval Authority regulation; Stability: This covers the analysis of stability against an agreed standard, survey and operator guidance. This is subject to Naval Authority regulation; Escape and Evacuation: This covers the arrangement, equipment, access, analysis, survey and operator guidance. This is subject to Naval Authority regulation; Hydrodynamics: This covers the analysis, model experiments and trials associated with resistance, propulsion, sea keeping and manoeuvring; Habitability: This includes all aspects of the warship associated with accommodation, stores, atmosphere, and husbandry covering both design of spaces and outfit. This does not include domestic systems that are covered under Marine Engineering; Seamanship: This includes the upper deck arrangements and equipment required for all seamanship evolutions.

Marine Engineering: Marine Engineering comprises propulsion and manoeuvring systems, ship systems, marine equipment selection and the Platform Management System. Notably Fire is exposed as a topic subject to Naval Authority regulation; Mission Systems: Mission Systems comprises the collation, management, distribution and processing of data onboard; including communications, sensors and C4I. In particular, integration with the P latform Management System; Combat System Engineering: Combat System Engineering concerns the physical aspects of combat systems - the set of men and machine resources that comprise the fighting capabilities of a warship. Essential subsystems include weapons/effectors, sensors, intelligence and information sources, and the combat management system. Whole Ship Issues - Whole Ship Issues are sub-divided into the following: •

•

•

Survivability: This includes susceptibility, vulnerability and recoverability; Electro-Magnetic Environment and Integrated Topside Design: This includes design, tests and trials; Ordnance, Munitions and Explosives Integration (OME): This covers the carriage, stowage and use of OME. This is subject to Naval Authority regulation.

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project •

Maritime Interoperability - Maritime Interoperability issues are sub-divided into: •

•

•

•

•

•

•

•

•

•

2

Chapter 4

Ship to air (aircraft, helicopters, UAV): Including design, equipment selection, analysis, tests and trials; Ship to underwater (UUV) This includes design, equipment selection, analysis, tests and trials; Ship to ship (RAS). This includes design, equipment selection, analysis, tests and trials; Ship to ship (boats): This includes design, equipment selection, analysis, tests and trials; Ship to shore (docks, ports): analysis, tests and trials;

This includes design, equipment selection,

Data Exchange: This covers the transmission of data between ships and other assets, while at sea and when alongside.

Safety: Safety covers both the safety management system and integration of regulation and certification for personnel, ship and environmental safety. Regulation of product safety is covered through the aforementioned technical subjects, i.e. Stability, Structure, Escape & Evacuation, OME and Fire; People: People covers both Human Factors Integration and training of operational staff; R&M: Reliability and maintainability covers design and testing of equipment to demonstrate acceptable reliability and arrangements f or maintenance; ILS: Integrated Logistic Support covers the arrangements for spares and support.

The following tables outline the tasks that need to be completed at each stage of a project. These may be used as guidance to a project and also provide a framework for assessing the maturity of a project during the various phases of acquisition from concept through to in-service. The tables have been taken from the Maritime System Maturity Model (Reference - SSG/103/1, Version 5, December 2006).

___________________________________________________________________________________________________________

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MAP 01-020 Warship Engineering Management Guide The Progression of a Warship Project Maritime System Maturity Level (MSML)

General Activities

Chapter 4

Key Integration Parameters Note 1 (KIPs) People Note 4

Detailed Requirements • • • • • • • • • •

R&M Note 4

• • • • •

ILS

Note 4

• • • •

•

Note 2

Detailed operability scenarios endorsed. Complement refined and broken down by specialty. Detailed Target Audience Descriptions available. Complete Allocation Of Function & human task analysis. Initial estimates of human performance & costs. HF trade-off activities complete. Style guide for Human Machine Interface defined. End users engaged in exploratory Human-In-The-Loop tests where necessary. HFI Plan produced. Training Needs Analysis matured and SRD informed. Define Reliability, Maintainability, Testability, Durability and Availability requirements for the solution. Confirm the definition of the mission relevant to system solutions. Produce detailed definitions of what constitutes mission failure or success. Support these requirements with an R&M Case Report (including a strategy and plan). R&M Risks reviewed in light of proposed solutions. Develop the ILS Strategy and plans. Develop the Support Strategy. Develop input into other project documentation (e.g. TLMP). Identify candidate Support Options for consideration and assess against the Support Solutions Envelope. Identify future initiatives that will affect logistic support.

Notes: 1

For each Key Integration Parameter sub-topic and for each System Maturity Level, maturity is to be assessed based on evidence of defined requirements and acceptance criteria/process.

2

Sub-System Development Items will be subject to separate system engineering life-cycle and system maturity evaluation. In many cases development will need to start in advance of ship life cycle. Some equipment will need to be ordered early (long lead items) in advance of ship construction contract (where applicable).

3

Term covers various forms of putting vessel afloat.


General Activities

Chapter 4


Detailed Requirements • • • • • • • • • •

R&M Note 4

• • • • •

ILS

Note 4

• • • •

•

Note 2

Detailed operability scenarios endorsed. Complement refined and broken down by specialty. Detailed Target Audience Descriptions available. Complete Allocation Of Function & human task analysis. Initial estimates of human performance & costs. HF trade-off activities complete. Style guide for Human Machine Interface defined. End users engaged in exploratory Human-In-The-Loop tests where necessary. HFI Plan produced. Training Needs Analysis matured and SRD informed. Define Reliability, Maintainability, Testability, Durability and Availability requirements for the solution. Confirm the definition of the mission relevant to system solutions. Produce detailed definitions of what constitutes mission failure or success. Support these requirements with an R&M Case Report (including a strategy and plan). R&M Risks reviewed in light of proposed solutions. Develop the ILS Strategy and plans. Develop the Support Strategy. Develop input into other project documentation (e.g. TLMP). Identify candidate Support Options for consideration and assess against the Support Solutions Envelope. Identify future initiatives that will affect logistic support.

Notes: 1

For each Key Integration Parameter sub-topic and for each System Maturity Level, maturity is to be assessed based on evidence of defined requirements and acceptance criteria/process.

2


3


4

Extracted from “System Readiness Levels (SRLs) – A Taxonomy to Assess and Communicate System Maturity version 2 dated 08/07/04.

5

Detailed Requirements in bold are assessed as part of Naval Authority assessment of progress towards certification.

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General Activities


Chapter 4 Detailed Requirements • • • •

R&M Note 4

• • • • •

ILS

Note 4

• • •

•

Note 2

Refine the HFI technical d ocumentation. Initial design of HMI defined. Detailed complement breakdown. Revise TLMP in light of detailed manning estimates. Continued development of the R&M Case – confirm sub-system design achieves characteristics. R&M requirements apportioned to sub-system level. Sub-system R&M Case developed. Risks flowed down and accepted by appropriate authority. R&M assurance methodology agreed. Develop a supportability work breakdown structure. Review Contractor’s support concepts ensuring SSE compliance and achieve stakeholder agreement. Trade off analysis – assess range of possible sub-systems proposed within the architecture to achieve a costeffective support solution. Record results in a logistics database.

Notes: 1

For each Key Integration Parameter sub-topic and for each System Maturity Level, maturity is to be assessed based on evidence of defined requirements and acceptance criteria/ process.

2


3


4


5



General Activities


Chapter 4 Detailed Requirements • • • •

R&M Note 4

• • • • •

ILS

Note 4

• • •

•

Note 2

Refine the HFI technical d ocumentation. Initial design of HMI defined. Detailed complement breakdown. Revise TLMP in light of detailed manning estimates. Continued development of the R&M Case – confirm sub-system design achieves characteristics. R&M requirements apportioned to sub-system level. Sub-system R&M Case developed. Risks flowed down and accepted by appropriate authority. R&M assurance methodology agreed. Develop a supportability work breakdown structure. Review Contractor’s support concepts ensuring SSE compliance and achieve stakeholder agreement. Trade off analysis – assess range of possible sub-systems proposed within the architecture to achieve a costeffective support solution. Record results in a logistics database.

Notes: 1


2


3


4


5


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General Activities

Chapter 4

Key Integration Parameters Note 1 (KIPs) R&M Note 4

Detailed Requirements • • •

ILS

Note 4

• • •

Note 2

Continued development of the R&M Case – Confirm detailed design achieves R&M characteristics. R&M requirements apportioned to components. Virtual Maintainability assessment undertaken (if appropriate). Ensure integration of supportability stakeholders’ activities. Non-economic Level of Repair Analysis (LORA) completed. Ensure that through life issues have been identified. (e.g. Obsolescence, Disposal, Configuration Management, WLC etc.).

Notes: 1


2


3


4


5



General Activities

Chapter 4

Key Integration Parameters Note 1 (KIPs) R&M Note 4

Detailed Requirements • • •

ILS

Note 4

• • •

Note 2

Continued development of the R&M Case – Confirm detailed design achieves R&M characteristics. R&M requirements apportioned to components. Virtual Maintainability assessment undertaken (if appropriate). Ensure integration of supportability stakeholders’ activities. Non-economic Level of Repair Analysis (LORA) completed. Ensure that through life issues have been identified. (e.g. Obsolescence, Disposal, Configuration Management, WLC etc.).

Notes: 1


2


3


4


5


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General Activities

Chapter 4

Key Integration Parameters Note 1 (KIPs) Maritime Interoperability

Detailed Requirements • • • • • •

Safety Note 4

• • • • • • •

People Note 4

• • •

R&M Note 4

ILS

Note 4

• • •

Note 2

Ship to air (aircraft, helicopters, UAV). Arrangements inspected and subject to initial testing. Ship to underwater (UUV). Arrangements inspected and subject to initial testing. Ship to ship (RAS). Arrangements inspected and subject to initial testing. Ship to ship (boats). Arrangements inspected and subject to initial testing. Ship to shore (docks, ports). Arrangements inspected and subject to initial testing. Data Exchange. Demonstration of interoperability using demonstration/testbed facilities. Safety and environmental assessments refined and reviewed by safety r egulators and authorities. Collect and analyse material state data to verify safety criteria. Verify material state of sub-systems. Specify in-service requirements for data capture to maintain design intent and maintain safety targets. Operator instructions and guidance drafted. Review and update Safety Case. Review all safety planning activities. Continuing operability trials conducted with end users to refine d esign. Continue the HFI management activities as the design matures. Verify Operational and Training Performance and Statements (OPS & TPS). Continued development of the R&M Case. Additional verification not covered by 5 above. Refine logistics models.

Notes: 1


2


3


4



General Activities

Chapter 4

Key Integration Parameters Note 1 (KIPs) Maritime Interoperability

Detailed Requirements • • • • • •

Safety Note 4

• • • • • • •

People Note 4

• • •

R&M Note 4

ILS

Note 4

• • •

Note 2

Ship to air (aircraft, helicopters, UAV). Arrangements inspected and subject to initial testing. Ship to underwater (UUV). Arrangements inspected and subject to initial testing. Ship to ship (RAS). Arrangements inspected and subject to initial testing. Ship to ship (boats). Arrangements inspected and subject to initial testing. Ship to shore (docks, ports). Arrangements inspected and subject to initial testing. Data Exchange. Demonstration of interoperability using demonstration/testbed facilities. Safety and environmental assessments refined and reviewed by safety r egulators and authorities. Collect and analyse material state data to verify safety criteria. Verify material state of sub-systems. Specify in-service requirements for data capture to maintain design intent and maintain safety targets. Operator instructions and guidance drafted. Review and update Safety Case. Review all safety planning activities. Continuing operability trials conducted with end users to refine d esign. Continue the HFI management activities as the design matures. Verify Operational and Training Performance and Statements (OPS & TPS). Continued development of the R&M Case. Additional verification not covered by 5 above. Refine logistics models.

Notes: 1


2


3


4


5


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5

Chapter 5

ACRONYMS AND GLOSSARY Acronym/Term

Explanation

A&A ACV ADD ALARP AMR AMS ANV AoC AR&M ARM&T AVCAT BITE BOST 0BR BS C4I CA

Alteration and Addition Air Cushion Vehicle Architecture Design Description As Low As Reasonably Practicable Auxiliary Machinery Rooms Acquisition Management System Alternative Naval Vehicles Acceptance of Contract Availability, Reliability & Maintainability Availability, Reliability, Maintainability and Testability AViation CATegory Fuel (also known as FSII, NATO F-44 or US JP-5) Built In Test Equipment Basic Operational Sea Training Book of Reference British Standards Command, Control, Communications, Computers and Intelligence Contract Acceptance


5

Chapter 5

ACRONYMS AND GLOSSARY Acronym/Term

Explanation

A&A ACV ADD ALARP AMR AMS ANV AoC AR&M ARM&T AVCAT BITE BOST 0BR BS C4I CA CAD CADMID CAE CAM CC CCTOs CE CERs CGT CMM COC COEIA C of G, CG ConEmp ConOps ConUse COSHH COTS CUM CS CSTs CV CWGs DA DBM DC DEC DefStans DESs DH DI DLO DLOD DMS DPA EBAs/IBAs EBS ECC

Alteration and Addition Air Cushion Vehicle Architecture Design Description As Low As Reasonably Practicable Auxiliary Machinery Rooms Acquisition Management System Alternative Naval Vehicles Acceptance of Contract Availability, Reliability & Maintainability Availability, Reliability, Maintainability and Testability AViation CATegory Fuel (also known as FSII, NATO F-44 or US JP-5) Built In Test Equipment Basic Operational Sea Training Book of Reference British Standards Command, Control, Communications, Computers and Intelligence Contract Acceptance Computer Aided Design Concept Assessment Development Manufacturing In service Disposal Computer Aided Engineering Computer Aided Manufacture Configuration Control Cost Capability Trade Offs Concurrent Engineering Cost Estimating Relationships Compensated Gross Tonne Contract Modification Margin Condition of Certification Combined Operational Effectiveness and Investment Appraisal Centre of Gravity Concept of Employment Concept of Operations Concept of Use Control of Substances Hazardous to Health Commercial Off The Shelf Capability Upgrade Margin Combat Systems Contractor’s Sea Trials Aircraft carrier Capability Working Groups Design Authority Design & Build Margin Damage Control Director of Equipment Capability Defence Standards Data Exchange Specifications Duty Holder Defence Instruction Defence Logistics Organisation Defence Line of Development Document Management System Defence Procurement Agency External/Internal Business Arrangements Environmental Baseline Study Engineering Change Control

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Acronym/Term

Explanation

ECP EDM EENA EHFA ELFEF EMC EME EMI ERM ESBU FATs FBNW FDI FFBNW FM FMEA FOC FTR FWA GA GFE GM GNS HATs HF HFE HFI HMI HVAC IA IAB IGM IIs ILS IMO IOC IPDE IPDM IPMD IPM IPR IPT IR ISD ISO ISRD ITD ITEA ITEAP ITT KIPs LCG LCU LDTD LFE LoDs LORA LPD(R)

Engineering Change Proposal Electronic Data Management Escape and Evacuation Naval Authority Early Human Factors Analysis Extremely Low Frequency Electric Fields Electro-Magnetic Compatibility Electro-Magnetic Environment Electro Magnetic Interference Enterprise Resource Planning Equipment Support Business Unit Factory Acceptance Tests For But Not With Fleet Date Inspection Fitted For But Not With Facility Management Failure Modes and Effects Analysis First Of Class Fit To Receive Fleet Weapon Acceptance General Arrangement Government Furnished Equipment Metacentric height General Naval Specification Harbour Acceptance Trials Human Factors Human Factors Engineering Human Factors Interface Human Machine Interface Heating Ventilation and Air Conditioning Incremental Acquisition Investment Appraisal Board In service Growth Margin Installation Inspections Integrated Logistics Support International Marine Organisation Initial Operating Capability Integrated Product Data Environment Integrated Product Data Management Installation Provision made in Design Integrated Product Model Intellectual Property Rights Integrated Project Team Infra-Red In Service Date International Organisation for Standardisation In Service Reliability Data Integrated Topside Design Integrated Test Evaluation and Acceptance Integrated Test Evaluation and Acceptance Plan Invitation To Tender Key Integration Parameters Longitudinal Centre of Gravity Landing Craft Utility Logistic Documentation and Technical Data Learning from Experience Lines of Development Level of Repair Analysis Replacement Landing Platform Dock

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Chapter 5

Acronym/Term

Explanation

LPH LSA MARPOL MARS MC MCA MCMV MilSpecs MLPB MoD MOE MOP MOTS MRP MSI MSM MSML MTBF MTTR NA Exp. NATO NBC NBCD NEC NES NFRs NOC NPV NSC NSCA NTP PC OA OEMC OEMs OME OPDEFs OPS & TPS PBS PCO PCO PDM PfP PIM R&D RAF R&M RADB RADHAZ RAS RATTAM RCS RFA RIBs RN ROM ROMP Ro-Ro SA

Landing Platform Helicopter Logistic Support Analysis The International Convention for the Prevention of Pollution from Ships Maritime Afloat Replenishment Ship Military Capability Maritime and Coastguard Agency Mine Countermeasures Vessel Military Specifications Maritime Logistics Programme Board Ministry of Defence Measures Of Effectiveness Measures Of Performance Military Off The Shelf Manufacturing Resource Planning Motion Sickness Incidence Maritime System Maturity Maritime System Maturity Level Mean Time Between Failure Mean Time To Repair Naval Authority Explosives North Atlantic Treaty Organisation Nuclear Biological Chemical Nuclear biological and chemical defence Networked Enabled Capability Naval Engineering Standard Non-Functional Requirements Non-Operational Computer Net Present Value Naval Ship Code National Society for Clean Air Naval Technical Publications Policy Committee Operational Analysis Other Elements of Military Capability Original Equipment Manufacturers Ordnance, Munitions and Explosives Operational Defects and Deficiencies Operational and Training Performance and Statements Product Breakdown Structure Prime Contract office Prime Contract Organisation Product Data Model Partner for Peace Product Information Model Research and Development Royal Air Force Reliability and Maintainability Requirements and Acceptance Database Radiation Hazard Replenishment at Sea Response to ATTack on Ammunition Radar Cross Section Royal Fleet Auxiliary Rigid Inflatable Boats Royal Navy Rough Order of Magnitude Risk and Opportunity Management Plan Roll On Roll Off System Acceptance

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Acronym/Term

Explanation

SARC SATs SDC SES SIB SME SMS SOLAS SRD SSE SSMOB STANAGs STE STG STW TA TAD TCG TDs TEWA TLC TLMP TNA TNT TRL TTI TTP UAV UEP UPC URD USN UUV UXE V&V VCG WBS WEMG WIG WLC WT XB

Safety And Readiness Check Sea Acceptance Trials Shop floor Data Capture Surface Effect Ship Stability Information Booklet Subject Matter Expert Safety Management System Safety of Life at Sea System Requirement Document Submerged Signal Ejector Ship Staff Move On Board NATO Standardization Agreement Support and Test Equipment Sea Technology Group Set To Work Technical Authority Target Audience Description Transversal Centre of Gravity Technical Documents Threat Evaluation and Weapons Assignment Through Life Cost Through Life Management Plan Training Needs Analysis TriNitroToluene Technology Readiness Level Tests, Trials and Inspections Tactics, Techniques and Procedures Unmanned Air Vehicle Underwater Electric Potential Unit Production Cost User Requirement Document United States Navy Unmanned Underwater Vehicle Upkeep by Exchange Verification and Validation Vertical Centre of Gravity Work Breakdown Structure Warship Engineering Management Guide Wing In Ground effect Whole Life Cost Watertight Executive Board

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MAP 01-020 Warship Engineering Management Guide References & Bibliography

6

Chapter 6

REFERENCES & BIBLIOGRAPHY

6.1

REFERENCES The references used in the WEMG are shown in Table 6-1.

[01] [02] [03] [04] [05]

Name Maritime System Maturity Andrews, D. J. “Creative Ship Design” Marine Design - Can Systems Engineering Cope? UCL MSc Systems Engineering Course Systems Engineering and Smart Procurement

Reference, Issue & Date STG/103/1, Issue 2, July 2004 Trans. RINA 1981 W.J. van Griethuysen, UCL www.syseng.ucl.ac.uk DERA/LS(SED)/3/1 (13 Jan 1999)

Table 6-1 References used in WEMG 6.2

BIBLIOGRAPHY

6.2.1

General Andrews D J, Burger D and Zhang J-W: - 'Design for Production using the Design Building Block Approach', RINA International Journal of Maritime Engineering, 2005. Andrews D J & Bayliss J A: - 'Computer Aided Topside Integration for Concept Design' RINA Warship June 1998. Proceedings of the Royal Society, Series A(1998) 454, p.187-211, Jan 1998. Royal Academy of Engineering: Three Reports on Managing Engineering Risk Jan 2003 (Title of each is relevant) Leopold, R and Reuter, W: ‘Three Winning Designs - FDL, LHA, DD963 Methods and Selected Features’, Trans SNAME 1971. Boxall, P et al :’Advanced Evacuation Simulation Software and its Use in Warships’, RINA Conference on Human Factors in Ship Design, Safety & Operation, Feb 2005, London.

6.2.2

Survivability Martin A. ‘The Place of Survivability in the Design of Future Surface Warships’, RINA Warship 98 Surface Warships The Next Generation Manley, D: ‘Procuring for Survivability’, RINA Warship 2001 Conference, London, June 2001.

6.2.3

HF General Castle. J. E., Plato, A. I., Feago, R. P. ‘Human Factors in Naval Ship Design’, SNAME 1983 Ware, H. D. ‘Habitability in Surface Warships’, RINA 1986

6.2.4

Safety Brown, D. K., Chalmers, D. W. ‘The Management of Safety in the RN’, Transactions RINA 1989 Rudgley, G. ‘The Management and Regulation of MoD Ship Safety’, STG/181/4/1/1/1, October 2000

6.2.5

Ship Motion ‘Common Procedures for Seakeeping in the Ship Design Process’, STANAG 4154

6.2.6

Ship Design Andrews, D. J. ‘Preliminary Design of Warships’, RINA 1994 Andrews, D. J. ‘Marine Design, Requirement Elucidation Rather than Requirement Engineering’, Journal of Naval Engineering, Dec 2004 Brown, D. K. ‘Defining a Warship’, Naval Engineers Journal, March 1986 Brown, D. K. ‘What is Good Design?’, Naval Review

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Chapter 6

Bryson, L. ‘The Procurement of a Warship’, RINA 1984 Heather, R.G. ‘Preliminary Design Considerations for Fast Warships’, RINA W arship 90 Honnor, A. F., Andrews, D. J. ‘HMS Invincible First of a New Generation of Aircraft Carrying Ships’, TRINA 1981 Leopold, R. ‘Innovation Adoption in Naval Ship Design’, US Naval Engineers Journal, Dec 1977 Rawson, K. J. ‘Ethics and Fashion in Design’, Tr ansactions RINA 1990 Thomas, T. R., Easton, M. ‘The Type 23 Duke Class Frigate’, TRINA 1992 Tibbets, B., Keane, R. G. ‘Making Design Everybody’s Job’, US Naval Engineers Journal ASNE May 1995 6.2.7

Design Structure Matrix Method Eppinger, S. D. ‘A Model Based Method for Organising Tasks in Product Development’, Research in Engineering Design, v6, 1994 Scott, J. ‘A Modelling Strategy for the Scheduling of Design Development Activities, A Case Study Based on a Warship’s Pre-Contract Design Definition’, Newcastle EDC, May 1998

6.2.8

ANVs ‘ANEP on the Application of Costing and Operational Effectiveness Methodologies for the Selection of Hull Types’, ANEP 52

6.2.9

Concept Design Andrews, D. J. ‘Preliminary Warship Design’, TRINA 1994 Andrews, D. J. ‘Requirements Elucidation’, IMDC 03 and JNE 2004 Garzke, W. H., Kerr, G. ‘Major Factors in Frigate Design’, SNAME 1981 Garzke, W. H., Kerr, G. ‘A New Warship Design Strategy – a Perspective’, SNAME 1985 Griethuysen, W J. van. ‘On the Choice Of Monohull Warships Geometry’ RINA 1994 Heller, S. R. ‘The Effects of Small Changes in Principal Dimensions on Ship Structural Weight’, Naval Engineers Journal, April 1972 Howell, J., Graham, C. ‘Marginal Weight Factors for Surface Combatant Ships’, 13th Symposium of Engineers and Scientists in US Air and Sea Systems Commands, Washington 1976 Kern, P. H., Kelly, J. R. ‘US Navy Weight and KG Margins Revisited’, 42nd Conference of the Society of Allied Weight Engineers, Anaheim Cal, 1980 Lehman, J. ‘Investigation of Ticonderoga’, House of Representatives, Committee on Armed Services, 1982 Rains, D. A. ‘Surface Combatant Technology Directions for the US Navy’, Naval Engineers Journal, March 1984

6.2.10

Alternative hull forms Andrews, D. J., Zhang, J-W. ‘Considerations in the Design of a Trimaran’, RINA Fast Vessels Symposium, Nov 1995 Kennel, C. ‘SWATH Ships’, Technical and Research Bulletin No. 7-5 SNAME 1992

6.2.11

Integration issues Burt, T. E. ‘Combat System Integration in the US Navy’, International Defence Review, 1/86 Gates, P. J. ‘Cellularity, an Advanced Weapon Electronics Integration Technique’, RINA 1985

6.2.12

Naval Architecture Brown, D. K. ‘The Architecture of Fr igates’, RINA ASW Symposium, 1987

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WEMG December 2007

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