NES 339 Requirements for Steering and Stabilizer Systems for HM Surface Ships and Royal Fleet...

Requirements for Steering and StabilizerSystems for HM Surface Ships and Royal

Fleet Auxiliaries

NOTEThis standard is Provisional

If you have difficulty with its applicationPlease advise UK Defence Standardization

Ministry of Defence INTERIM Defence Standard 02-339

Issue 2 Publication Date 15 August 2002

Category 1

AMENDMENTS ISSUED SINCE PUBLICATION

AMD NO DATE OFISSUE

TEXT AFFECTED SIGNATURE &DATE

Revision Note

This Issue of this Standard has been prepared to incorporate changes to text and presentation.The technical content has been updated in line with current practice.

Historical Record

Def Stan 02-339 Issue 1 1 April 2000Def Stan 02-340 Issue 1 1 April 2000NES 339 Issue 1 December 1989NES 340 Issue 1 November 1989

Sponsor (MDMS8a3): UK Defence StandardizationStandards Programme Manager 9Room 1138Kentigern House65 Brown StreetGlasgow G2 8EX

Your Reference :

Our Reference : D/DStan/69/02/339

Date : 15 August 2002

INTERIM DEFENCE STANDARD - INVITATION TO COMMENT

Interim Defence Standard 02-339/Issue 2

Title: Requirements for Steering and Stabalizer Systems for HM Surface Ships and Royal FleetAuxiliaries.

Any comments on this INTERIM document are to be returned to the above address.

The purpose of this form is to solicit any beneficial and constructive comment that will assistthe author and/or working group to finalise the above standard for full publication.

Comments are to be entered below and any additional pertinent data which may also be of usein improving the standard should be attached to this form and returned to writer at the aboveaddress. A full review of the document will take place within one year of being published asan Interim standard.

No acknowledgement to comments received will normally be issued.

NAME: B McALISTER SIGNATURE: BRANCH: DSTAN___________________________________________________________________________

1. Does any part of the standard create problems or require interpretation:

YES NO If ‘yes’ state under section 3:a. the clause number(s) and wording;b. the recommendation for correcting the deficiencies.

2. Is the Defence Standard restrictive:

YES NO If ‘yes’ in what way, state under section 3.

Continued over

3. Comments, general or any requirement considered too rigid:

Page Clause Comments Proposed Solution

4. I/We agree that this Interim Standard, subject to my/our comments being taken into consideration, whenpublished in final form will cover my/our requirements in full. Should you find my/our comments atvariance with the majority, I/we shall be glad of the opportunity to enlarge upon them before finalpublication.

Signature.................................................................Representing.......................................................

Submitted by (print or type name and address)Telephone number:

Date:

Our Ref:

1

INTERIM DEFENCE STANDARD 02–339 (NES 339)

REQUIREMENTS FOR STEERING AND STABILIZER

SYSTEMS FOR HM SURFACE SHIPS AND ROYAL FLEET

AUXILIARIES

ISSUE 2

This Defence Standard is

authorized for use in MOD contracts

by the Defence Procurement Agency and

the Defence Logistics Organization

Published by:

Defence Procurement AgencyAn Executive Agency of The Ministry of DefenceUK Defence StandardizationKentigern House65 Brown StreetGlasgow G2 8EX

INT DEF STAN 02–339 / Issue 2

(NES 339)

2

SCOPE

1. This Defence Standard (DEF STAN) 02�339, in conjunction with the documents referred toherein, specifies the design requirements for Steering and Stabilizer Systems in HM SurfaceShips and Royal Fleet Auxiliaries (RFA).

2. This Defence Standard provides guidance on the environmental conditions in which theequipment shall operate and remain fully functional. It also provides guidance on safety,testing, installation, inspection Setting to Work (STW), trials and preservation requirements.

3. Details of hydrodynamic parameters of Rudder and Stabilizer Fin design are not covered inthis Standard, Where relevant, reference shall be made to the requirements of the SystemRequirement Document (SRD).


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FOREWORD

Sponsorship

1. This Defence Standard is sponsored by the Warship Support Agency (WSA), Ministry ofDefence (MOD).

2. Any user of this Standard either within MOD or in industry may propose an amendment toit. Proposals for amendments that are not directly applicable to a particular contract are tobe made to the publishing authority identified on Page (i), and those directly applicable to aparticular contract are to be dealt with using contract procedures.

3. If it is found to be unsuitable for any particular requirement MOD is to be informed in writingof the circumstances.

4. No alteration is to be made to this Standard except by the issue of an authorized amendment.

5. Unless otherwise stated, reference in this Standard to approval, approved, authorized andsimilar terms, means by the MOD in writing.

6. Any significant amendments that may be made to this Standard at a later date will be indicatedby a vertical sideline. Deletions will be indicated by 000 appearing at the end of the lineinterval.

7. This standard has been reissued to reflect changes in Departmental Nomenclature due to theMOD reorganization and the changes to technical requirements.

Conditions of Release

General

8. This Defence Standard has been devised solely for the use of the MOD, and its contractors inthe execution of contracts for the MOD. To the extent permitted by law, the MOD herebyexcludes all liability whatsoever and howsoever arising (including but without limitation,liability resulting from negligence) for any loss or damage however caused when the Standardis used for any other purpose.

9. This document is Crown Copyright and the information herein may be subject to Crown orthird party rights. It is not to be released, reproduced or published without written permissionof the MOD.

10. The Crown reserves the right to amend or modify the contents of this Standard withoutconsulting or informing any holder.

MOD Tender or Contract Process

11. This Standard is the property of the Crown. Unless otherwise authorized in writing by theMOD must be returned on completion of the contract, or submission of the tender, inconnection with which it is issued.

12. When this Standard is used in connection with a MOD tender or contract, the user is to ensurethat he is in possession of the appropriate version of each document, including relateddocuments, relevant to each particular tender or contract. Enquiries in this connection maybe made to the authority named in the tender or contract.

13. When Defence Standards are incorporated into MOD contracts, users are responsible for theircorrect application and for complying with contractual and other statutory requirements.Compliance with a Defence Standard does not of itself confer immunity from legal obligations.


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Categories of Naval Defence Standard

14. The Category of this Standard has been determined using the following criteria:

a. Category 1. If not applied may have a Critical affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

b. Category 2. If not applied may have a Significant affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

Through life costs and support.

c. Category 3. If not applied may have a Minor affect on the following:

MOD best practice and fleet commonality.

Corporate experience and knowledge.

Current support practice.

Related Documents

15. In the tender and procurement processes the related documents listed in each section andAnnex A can be obtained as follows:

a. British Standards British Standards Institution,389 Chiswick High Road,London, W4 4AL

b. Defence Standards Defence Procurement AgencyAn Executive Agency of the Ministry of DefenceDirectorate of StandardisationKentigern House65 Brown StreetGlasgow, G2 8EX.

c. Other documents Tender or Contract Sponsor to advise.

16. All applications to the MOD for related documents are to quote the relevant MOD Invitationto Tender or Contract number and date, together with the sponsoring Directorate and theTender or Contract Sponsor.

17. Prime Contractors are responsible for supplying their subcontractors with relevantdocumentation, including specifications, standards and drawings.

Health and Safety

Warning

18. This Defence Standard may call for the use of processes, substances and/or procedures thatare injurious to health if adequate precautions are not taken. It refers only to technicalsuitability and in no way absolves either the supplier or the user from statutory obligationsrelating to health and safety at any stage of manufacture or use. Where attention is drawn tohazards, those quoted may not necessarily be exhaustive.

19. This Standard has been written and is to be used taking into account the policy stipulated inJSP 430: MOD Ship Safety Management System Handbook.

Additional Information

20. (There is no relevant information included.)


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CONTENTSPage No

SCOPE 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FOREWORD 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sponsorship 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conditions of Release 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Categories of Naval Defence Standard 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Documents 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Health and Safety 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Additional Information 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CONTENTS 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 1. PERFORMANCE SPECIFICATION 9. . . . . . . . . . . 1.1 Steering Systems 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.1 Systems Aims and Concept 9. . . . . . . . . . . . . . . . . . . . 1.1.2 Overall System Accuracy 9. . . . . . . . . . . . . . . . . . . . . . 1.1.3 Rudder Movement 9. . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.4 Rudder Actuation 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.5 Rudder Angle Indication 10. . . . . . . . . . . . . . . . . . . . . . 1.1.6 Electric Motors 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.7 Availability 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Autopilot 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.1 Overall System Performance 10. . . . . . . . . . . . . . . . . . 1.2.2 Course Keeping Accuracy 10. . . . . . . . . . . . . . . . . . . . . 1.2.3 Course Changing Accuracy 11. . . . . . . . . . . . . . . . . . . . 1.3 Stabilizer Systems 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.1 System Aims and Concepts 11. . . . . . . . . . . . . . . . . . . . 1.3.2 Control Characteristics 11. . . . . . . . . . . . . . . . . . . . . . . 1.3.3 Availability 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Emergency Operation 12. . . . . . . . . . . . . . . . . . . . . . . .

SECTION 2. NATIONAL/INTERNATIONAL REGULATIONS 122.1 Maritime Pollution Control 12. . . . . . . . . . . . . . . . . . . . 2.2 Safety 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 3. MILITARY STANDARDS/REQUIREMENTS 12. . . . 3.1 Drawings 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Environmental and Operational Conditions 12. . . . . . 3.3 Electrical Power Control and Monitoring System 12. 3.3.1 Power Supplies 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.2 Controls and Remote Controls 13. . . . . . . . . . . . . . . . . 3.3.3 Operational Indications 13. . . . . . . . . . . . . . . . . . . . . . . 3.3.4 Fault Alarm Circuits 14. . . . . . . . . . . . . . . . . . . . . . . . . 3.3.5 Motor Controls 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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3.3.6 Electric Motors 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.7 Electrical Safety 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 Equipment Selection 15. . . . . . . . . . . . . . . . . . . . . . . . . 3.4.1 General 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.2 Screw Threads 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.3 Instrumentation 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.4 Electronic Components 16. . . . . . . . . . . . . . . . . . . . . . . 3.4.5 Electrical Connections 16. . . . . . . . . . . . . . . . . . . . . . . . 3.4.6 Glands and Seals 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.7 Rudder Stops 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.8 Pipework 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.9 Valves and Cocks 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.10 Ball and Roller Bearings 17. . . . . . . . . . . . . . . . . . . . . . 3.4.11 Noise, Shock and Vibration 17. . . . . . . . . . . . . . . . . . . . 3.4.12 Electromagnetic Compatibility 17. . . . . . . . . . . . . . . . . 3.4.13 Nuclear Hardening 17. . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 Lubrication 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6 Safety 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.7 Castings 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.8 Welding 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9 Marker Plates 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10 Preservation and Maintenance 18. . . . . . . . . . . . . . . . . 3.10.1 General 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10.2 Maintenance in Stores 18. . . . . . . . . . . . . . . . . . . . . . . . 3.10.3 Maintenance on Board 18. . . . . . . . . . . . . . . . . . . . . . . . 3.10.4 Flexible Hoses 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11 Testing, Installation Inspections and

Setting to Work 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11.1 General 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11.2 Testing Requirements 19. . . . . . . . . . . . . . . . . . . . . . . . . 3.11.3 Pressure Testing 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11.4 Testing After Manufacture 20. . . . . . . . . . . . . . . . . . . . 3.11.5 Installation Inspections 20. . . . . . . . . . . . . . . . . . . . . . . 3.11.6 System Preliminary Tests and Setting to Work 21. . . . 3.12 Trials 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12.1 General 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12.2 Preliminary Basin Trials 22. . . . . . . . . . . . . . . . . . . . . . 3.12.3 Basin Trials 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12.4 Contractors Sea Trials 24. . . . . . . . . . . . . . . . . . . . . . . . 3.12.5 Final Machinery Demonstration 24. . . . . . . . . . . . . . . .

SECTION 4. DESIGN REQUIREMENTS/GUIDANCE 25. . . . . . . 4.1 Design Parameters 25. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.1 General 25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.2 Fundamental Requirements 25. . . . . . . . . . . . . . . . . . . 4.1.3 Stabilizer System Aims and Concepts 26. . . . . . . . . . .


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4.1.4 Ship Characteristics 27. . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.5 Data Transmission 27. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.6 Environmental and Operational Conditions 27. . . . . . 4.1.7 General Design Objectives 28. . . . . . . . . . . . . . . . . . . . . 4.1.8 Upkeep Policy 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.9 Availability 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.10 Reliability 29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.11 Maintainability 29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.12 Vulnerability 30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.13 Interchangeability 30. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.14 Electronic Equipment Interchangeability 30. . . . . . . . 4.1.15 Materials and Weight 30. . . . . . . . . . . . . . . . . . . . . . . . . 4.1.16 Economy of Space 31. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.17 Ease of Operation 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.18 Emergency Hand Operation 31. . . . . . . . . . . . . . . . . . . 4.1.19 Software 32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.20 Electrical Equipment 32. . . . . . . . . . . . . . . . . . . . . . . . . 4.1.21 Lubrication System(s) 32. . . . . . . . . . . . . . . . . . . . . . . . 4.2 Steering Systems 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.1 System Partitioning 33. . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2 Control System 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 Rudder Angle Indication 33. . . . . . . . . . . . . . . . . . . . . . 4.2.4 Rudder Angle Feedback Transmitter 34. . . . . . . . . . . . 4.2.5 Navigation System 34. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.6 Hand Steering Units 34. . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.7 Test Facilities 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Autopilot 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.1 Definition of the Sub–System 35. . . . . . . . . . . . . . . . . . 4.3.2 Physical Characteristics 35. . . . . . . . . . . . . . . . . . . . . . . 4.3.3 Inputs 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.4 Outputs 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.5 Ship Characteristics 36. . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.6 Operator Displays and Controls 36. . . . . . . . . . . . . . . . 4.3.7 System Testing 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.8 Setting to Work 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.9 Test Facilities 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Stabilizing Systems 37. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.1 Stabilizer System Partitioning 37. . . . . . . . . . . . . . . . . 4.4.2 Control System 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.3 Stabilizer Fin Angle Indication 38. . . . . . . . . . . . . . . . . 4.5 Safety 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 5. CORPORATE EXPERIENCE & KNOWLEDGE 39. 5.1 Rudder and Stabilizer Fin Control 39. . . . . . . . . . . . . . 5.2 Electro Hydraulic Type System 40. . . . . . . . . . . . . . . . . 5.2.1 Rudder Servo System 40. . . . . . . . . . . . . . . . . . . . . . . . .


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5.2.2 Rudder Servo Amplifier 41. . . . . . . . . . . . . . . . . . . . . . 5.2.3 Stabilizer Fin Servo System 41. . . . . . . . . . . . . . . . . . . 5.2.4 Facilities of the Stabilizer Central Control Unit 42. . . 5.2.4.1 Stabilizer Fin Local Control Unit 43. . . . . . . . . . . . . . . 5.2.4.2 Stabilizer Fin Angle Feedback Transmitter 43. . . . . . 5.2.5 Steering and Stabilizer Hydraulic System 44. . . . . . . . 5.2.6 Hydraulic Pumps and Controls 44. . . . . . . . . . . . . . . . 5.2.7 Actuators 45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.8 Heat Exchangers 45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.9 Hydraulic Fluid Reservoirs 45. . . . . . . . . . . . . . . . . . . . 5.2.10 Hydraulic System Cleanliness 46. . . . . . . . . . . . . . . . . . 5.2.11 Relief Valve Arrangement 46. . . . . . . . . . . . . . . . . . . . . 5.2.12 Pipework 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.13 Valves and Cocks 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.14 Filtration 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.15 Hand Pump 46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.16 Electric Motors 47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.17 Pump Drive Couplings 47. . . . . . . . . . . . . . . . . . . . . . . . 5.2.18 Seals 47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.19 Materials 47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 5.1 Previously used Materials and Welding Guidance 48. 5.3 System Manuals 48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.1 Typical Contents 48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 System Preliminary Tests 49. . . . . . . . . . . . . . . . . . . . . .

ANNEX A RELATED DOCUMENTS 50. . . . . . . . . . . . . . . . . . . .

ANNEX B ABBREVIATIONS AND DEFINITIONS 54. . . . . . . .

ANNEX C PROCUREMENT CHECK LIST 57. . . . . . . . . . . . . . .

ALPHABETICAL INDEX 59. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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1. PERFORMANCE SPECIFICATION

Related Documents: DEF STAN 07�244; see also Annex ANNEX A.

1.1 Steering Systems

1.1.1 Systems Aims and Concept

a. Steering System:

(1) The function of the Steering System shall be to control the Rudder(s)angle to within specified tolerance at all Ship's speeds from Full Astern toFull Ahead. In addition, where an Autopilot is specified, this shouldcontrol Ship's head to within the required angle, from a minimum speedto Full Ahead. A facility is required where various modes of operation canbe selected by the helmsman.

(2) The helmsman at each control position shall be provided with manualcontrols and relevant navigation indications to permit control of Rudderangle and/or Ship's head as required by the Officer of the Watch (OOW).The facilities that shall be provided are described in Clause 4.2. TheRudder demand signal shall be fed to a Closed Loop Rudder ActuatingSystem.

(3) When using the Autopilot, the course required is normally manually setby the OOW or the Helmsman. Alternatively, the course to steer may beprovided from an external source, such as a Navigational Computer, or acorrection to the set course may be applied to maintain a given track.

(4) The overall system aim when in Autopilot control shall maintain theShip's heading in accordance with the parameters laid down in Clause 1.2.

1.1.2 Overall System Accuracy

a. Unless otherwise specified, the Steering System shall be capable of positioning

the Rudder with an accuracy of ±0.5� for Rudder angles up to 10� and

±5 per cent for greater angles. The error is the difference between demand atPrimary Steering Position (PSP) or Secondary Steering Position (SSP) and theactual Rudder angle measured at the Rudder Stock.

1.1.3 Rudder Movement

a. The required time and range of Rudder movement will normally be stated in theSystem Requirement Document (SRD). Where no data is provided thefollowing figures shall be used:

(1) Rudders shall be capable of moving from 35�Port to 35� Starboard;

(2) The time taken for the Rudder(s) to travel from 35� on one side to passing30� on the other side shall be 16 seconds or less in normal operation;

(3) The time taken for the Rudder(s) to travel from 35� on one side to passing30� on the other side shall be 28 seconds or less with half of the normalsystems resources in operation.

1.1.4 Rudder Actuation

a. For twin Rudder installations, the operating gear on one Rudder shall becapable of operating both Rudders together via a suitable link when theopposite operating gear is non�operational for whatever reason.


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1.1.5 Rudder Angle Indication

a. The Indication System shall have an overall accuracy of ±0.5� betweenRudder(s) position and indicated value.

1.1.6 Electric Motors

a. Motors shall be capable of developing maximum full load torque under all dutycycle conditions. Unless otherwise stated, overload requirements shall be inaccordance with DEF STAN 07�244.

1.1.7 Availability

a. The probable usage of the equipment will vary between installations. However,it should be assumed that the Steering Gear will be in continuous use whilst thevessel is at sea, with a minimum mission time of 45 days, unless statedotherwise in the SRD.

1.2 Autopilot

1.2.1 Overall System Performance

a. For all operating conditions, the Closed Loop Gain and Phase Margins for theControl Loop from Heading Error to Ship's Heading shall be at least 8 dB and60� respectively.

b. For all operating conditions, the Gain and Phase Margins for the Control Loopfrom Rudder demand via Rudder, Ship and Autopilot, shall be at least 8 dB and45� respectively.

c. Control Loops shall not demonstrate conditional stability throughout the rangeof operation of the system.

d. The bandwidth of the Rudder Demand Signal shall be less than the bandwidthof the Rudder Servo Loop.

e. Small signal discontinuities shall be less than ±0.25� of Rudder angle.

f. The control characteristics shall be agreed with the Design Authority andDefence Procurement Agency (DPA) at the earliest possible stage in the design,together with the technology that shall be used for generating them.

1.2.2 Course Keeping Accuracy

a. In sea conditions up to Sea State 4, with equivalent wind speeds, the maximum

course error shall be ±1.5� at any Ship's heading with respect to the sea.

b. In conditions between Sea State 4 and Sea State 7, the maximum course error

shall be ±3° at any Ship's heading with respect to the sea.

c. Above Sea State 7, the Autopilot shall continue to function and give the course

keeping performance in head seas (to ±45° of Ship's head) as specified inClause 1.2.2b. At headings other than those specified, degradation in the aboveperformance standard is acceptable.

d. The Autopilot shall achieve the above performance standards irrespective ofany steady torques imposed on the vessel, whether they be due to wind, currentor offset in the effective Rudder angle.


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e. The characteristics of the Autopilot shall self adjust automatically, as necessary,to maintain these performance standards within a Ship's speed range from8 knots up to the Ship's maximum speed. Between 4 knots and 8 knots, and insea states below Sea State 5, the Autopilot shall operate satisfactorily with a

degradation in performance of only ±1� on the figures in Clauses 1.2.2a. and1.2.2b.

f. Heading disturbances induced by the sea shall be attenuated by the SteeringSystem to the largest extent possible, consistent with minimum Rudderactivity. At frequencies where such heading disturbances are amplified by theSteering System, the amplification shall be below 3 dB.

1.2.3 Course Changing Accuracy

a. The Autopilot shall be capable of bringing the Ship's Head to any new setcourse. All course changes are normally conducted the `shortest way around'.However, where operational circumstances dictates, course changes may beconducted using the `longest way round'.

b. An overshoot of a maximum of 1� above the course keeping error shall beallowed whilst changing course. The vessel shall settle on the desired coursewith a maximum of two overshoots.

1.3 Stabilizer Systems

1.3.1 System Aims and Concepts

a. The Primary Function of the Stabilizer System shall be to reduce roll to aminimum at all forward speeds above some minimum value below which theStabilizer is ineffective. A facility shall be provided where various modes ofoperation can be selected by the operator. Thereafter, the operation of thesystem shall be entirely automatic, irrespective of Ship's speed or sea state.

b. The Secondary Function of the Stabilizer System shall be to induce a ForcedRoll, as required, to facilitate, pre�wetting of the ship for Nuclear, Biologicaland Chemical Defence (NBCD) purposes. See also Clauses 4.4.2e. and 5.2.4.

1.3.2 Control Characteristics

a. Control Loop gain and phase margins for the control loop from roll disturbanceto the vertical shall be at least 8 dB and 60� respectively.

b. Control Loops shall not demonstrate conditional stability throughout the rangeof operation of the system.

c. The bandwidth of the Stabilizer Fin Demand Signal shall be less than thebandwidth of the Stabilizer Fin Servo Loop.

d. Small signal discontinuities shall be less than ±0.25� of Rudder angle.

e. The control characteristics shall be agreed with the Design Authority andDefence Procurement Agency (DPA) at the earliest possible stage in the design,together with the technology that shall be used for generating them.

1.3.3 Availability

a. The probable usage of the equipment will vary between installations. However,it should be assumed that the Stabilizer System will be in continuous use whilstthe vessel is at sea, with a minimum mission time of 45 days, unless statedotherwise in the SRD.


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1.4 Emergency Operation

a. A suitable means of steering the vessel by hand, in emergency situations,capable of being operated by no more than two persons, shall be provided. Itshall be capable of moving the Rudder(s) to 10� at Ship speeds up to 10 knots.

b. A suitable means of centralizing and locking a single Rudder or Stabilizer Fin atzero Ships' speed shall be provided, which shall be capable of being operated byno more than two persons.

2. NATIONAL/INTERNATIONAL REGULATIONS

Related Documents: MARPOL 73/78; LOLER 1998; see also Annex ANNEX A.

2.1 Maritime Pollution Control

a. Steering and Stabilizer Systems, including all supporting systems, shall meetthe requirements of the International Convention for the Prevention ofPollution from Ships (MARPOL 73/78).

2.2 Safety

a. All portable and fitted lifting equipment shall comply with the LiftingOperations and Lifting Equipment Regulations 1998 (LOLER 1998).

3. MILITARY STANDARDS/REQUIREMENTS

Related Documents: MARPOL 73/78; BS EN 837�1; BS 4518; DEF STAN 00�52;DEF STAN 01�5; DEF STAN 02�32; DEF STAN 02�324 Part 1; DEF STAN 02�337Parts 1, 2 and 3; DEF STAN 02�341 Part 1; DEF STAN 02�350; DEF STAN 02�351;DEF STAN 02�352; DEF STAN 02�353;DEF STAN 02�354; DEF STAN 02�360;DEF STAN 02�514; DEF STAN 02�627; DEF STAN 02�636; DEF STAN 02�722;DEF STAN 02�723; DEF STAN 02�732; DEF STAN 02�745 Part 2; DEF STAN 02�797Part 1; DEF STAN 02�862 Part 1; DEF STAN 02�863; DEF STAN 07�244;DEF STAN 07�251; DEF STAN 07�254 Part 2; DEF STAN 08�107; DEF STAN 08�118Part 1; DEF STAN 08�123; DEF STAN 59�36; DEF STAN 59�41 Parts 2, 3, 4 and 7;DEF STAN 61�5 Parts 1 and 4; DEF STAN 66�2; BR 3021(1); BR 3021(2); BR 3026;BR 8470; BR 8471; BR 8472; BR 8473; DGS/PS 9023; see also Annex ANNEX A.

3.1 Drawings

a. Drawing requirements shall be stated in the SRD and managed in accordancewith DEF STAN 02�722.

3.2 Environmental and Operational Conditions

a. Unless otherwise stated, the Steering and Stabilizer System(s) shall meet therequirements for the design and testing of equipment as stated inDEF STAN 08�123 and the references contained therein.

b. The range of climatic conditions in which the Steering and Stabilizer Systemsshall remain fully operational shall be as stated in the SRD.

3.3 Electrical Power Control and Monitoring System

a. The Electric Power Control and Monitoring System (EPCMS) shall providepower and surveillance to the Steering and Stabilizer System(s). Thesefunctions may be incorporated in the overall Machinery Control andSurveillance (MCAS) system.


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3.3.1 Power Supplies

a. Connections from the vessel's Main Electrical Power Distribution System shallbe made at the Motor Starter Panels as follows:

(1) Steering: In each of the Rudder Operating Systems. Each starter shall beconnected to normal and alternative supplies via an AutomaticChange�over Switch (ACOS). These shall be derived from separateswitchboards and where an emergency switchboard is fitted at least onemotor shall have its normal supply derived from it;

(2) Stabilizers: In each of the Stabilizer Fin Operating Systems;

(3) Isolators shall be provided.

b. A suitable Low Power (LP) or other voltage supply, as required, shall be derivedat the Motor Starter Panel for distribution to related control and auxiliaryequipment, provided that the necessary reliability and vulnerability targets aremet.

c. DEF STAN 61�5 Parts 1 and 4 applies for voltage and frequency tolerances,transient excursions and other relevant characteristics.

3.3.2 Controls and Remote Controls

a. Unless otherwise specified, starting and stopping of Motors shall be by remotecontrol from the Ship Control Centre (SCC) with local control for starting andstopping available at Motor Starters.

b. For Steering Systems, the facility to START/STOP Motors at the EmergencySteering Position (ESP) shall be provided. Additionally, if the Starters and/orMotors are located in another compartment/space, control for starting andstopping shall be provided in the Steering Gear Compartment.

c. For Stabilizer Systems, the facility to Start/Stop Motors at the Stabilizer FinLocal Control Units (SFLCU) shall be provided.

3.3.3 Operational Indications

a. As a minimum, the EPCMS shall provide visual indication of the followingconditions:

(1) At the Bridge:

(a) Steering and Stabilizer System Motors, RUNNING/STOPPED;

(b) Steering mode, HAND/AUTOPILOT;

(c) Steering Control System, PORT/STARBOARD;

(d) Steering Control selected: PSP, SSP or ESP;

(2) At the SCC:

(a) Power available to Steering System Motors;

(b) Power available to Stabilizer System Motors;

(c) Steering System Motors, RUNNING/STOPPED;

(d) Stabilizer System Motors, RUNNING/STOPPED;

(e) Stabilization mode, NORMAL/QUIET;


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(3) At the SSP:

(a) Motors, RUNNING/STOPPED;

(b) Steering Control, PORT/STARBOARD;

(c) Steering Control selected: PSP, SSP or ESP;

(4) At the SFLCU:

(a) Power available to Stabilizer System Motors;

(b) Motors, RUNNING/STOPPED;

(c) Local/Remote control selected.

3.3.4 Fault Alarm Circuits

a. As a minimum, the EPCMS shall provide indication of the following conditions:

(1) At the SCC:

(a) Steering System power failure;

(b) Stabilizer System power failure;

(c) Steering System fluid reservoir temperature and level (if applicable);

(d) Stabilizer System fluid reservoir temperature and level (if applicable);

(e) Steering System Motors overheat;

(f) Stabilizer System Motors overheat;

(g) Stabilizer Fin limit exceeded;

(2) At the Bridge Only:

(a) Log input to Autopilot failure;

(b) Autopilot `Off Course' alarm;

(c) Autopilot failure;

(3) At the Bridge and SSP:

(a) Steering System Port/Starboard Control Channel failure;

(b) Steering System Motors tripped;

(c) Steering System Port/Starboard Power Unit failure.


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3.3.5 Motor Controls

a. Local and remote controlled Motor Starters are required.

b. Positive temperature coefficient thermistors shall be incorporated in thewindings of the main motors to sense an over�temperature condition, inaccordance with DEF STAN 07�244.

c. A motor thermal protection unit housed in the Motor Starter(s) shall raise analarm in the SCC should an over�temperature condition be sensed where onlyone system is running. This shall initiate an Automatic Change�over (ACO) tothe standby system to be be activated and shall not cause loss of steering abilityat any time.

d. Provision shall be provided in Motor Starter(s) for the installation of an ElapsedTime Meter (ETM) where required.

e. Contactors, relays, switches and fuses for the control of Motors in the Steeringand/or Stabilizer Systems shall be housed in the Motor Starters, theconstruction of which shall be in accordance with DEF STAN 02�636.


a. General requirements for the design and manufacture of rotating electricalmachinery shall be in accordance with DEF STAN 02�627 andDEF STAN 07�244.

3.3.7 Electrical Safety

a. Arrangements for the Safety of Electrical Equipment and the use of switches,indicator lamps, fuses, safety devices and earth grounding arrangements shallconform to the requirements of DEF STAN 08�107.

3.4 Equipment Selection

3.4.1 General

a. Selection of electrical and electronic components shall be in accordance withDEF STAN 59�36 where possible.

b. The choice of all equipment in a system design should be made with fullknowledge of the conditions required for operation and should aim to reducethe number of different equipments introduced into service. Where possible,equipment should be selected from equipment already in service. Type tests ofnew equipment should be undertaken by the Prime Contractor where requiredto prove fitness for purpose or where called for in the SRD.

c. Where fitted, Hydraulic Systems shall be capable of operating with OX 40 fluid.

3.4.2 Screw Threads

a. Wherever possible, screwed fasteners and screw threads shall be selected fromDEF STAN 02�862 Part 1.

3.4.3 Instrumentation

a. Where required, Pressure Gauges shall conform to DEF STAN 66�2 and shall bemanufactured by DPA approved makers. No other gauges shall be used unlessprior approval has been obtained from DPA.

b. Pressure Gauges for 60 bar and above shall be of safety pattern type with blowout backs. A clearance of 20 mm shall be maintained at the rear of the gauge.


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c. Pressure Gauges shall be provided with isolating cocks/valves at source,conforming to the Working Pressure (WP) of the system.

d. A Gauge Board carrying all system Pressure Gauges shall be provided andinstalled in a position where it can clearly be seen for operational andmaintenance purposes. Where the Gauge Board is mounted `off' theequipment, agreement between the System Designer and the Shipbuilder on itssize and siting shall be reached. The installation and testing of Pressure Gaugesshall conform to BS EN 837�1.

e. Where specified, Thermometers, Temperature Tapping points andTemperature Sensors shall be as follows:

(1) Graduations/readouts in °C;

(2) Liquid in Glass Thermometers, Pockets and Holders shall conform toDEF STAN 02�732;

(3) Overall temperature monitoring of any Hydraulic System(s) shall beprovided by a MOD approved Transducer situated in the fluid reservoir orat a suitable point in the hydraulic circuit as appropriate. The transducershall provide a read�out at the SCC and also operate the high temperaturewarning;

(4) Local temperature monitoring of any Hydraulic System(s) shall beprovided by MOD approved Thermometers adjacent to Hydraulic Pumpconnections.

f. The Prime Contractor shall be responsible for arranging the instrumentation,including Isolating Valves, Thermometer Pockets, facings and tapped bosses asspecified in the SRD.

3.4.4 Electronic Components

a. All small electronic components shall be mounted on plug�in Printed CircuitBoards (PCB). Edge connectors are not acceptable and boards shall be fittedwith appropriately sized plug and socket connectors, with gold plated contacts.The plug�in PCB shall have test points brought out to pins accessible to themaintainer.

3.4.5 Electrical Connections

a. The cable entries and terminations for input and output connections to all unitsshall be selected from DEF STAN 02�514 or MOD approved plugs and socketsshall be used.

3.4.6 Glands and Seals

a. Rudder Stock and Stabilizer Fin Hull Glands shall be of a form wherebyrenewal or repairs do not necessitate docking the vessel.

b. If stuffing box type glands are specified for valves in any part of the system,gland stuffing boxes shall be of adequate depth for the purpose. Glands shall beof generous proportions to preclude distortion during tightening down inservice.

c. Sealing arrangements shall be suitable for the required duty, Naval StoresCatalogue packings being used wherever possible. They shall benon�adjustable, and of a split design to facilitate maintenance.

d. Finshaft hull glands are to be selected in accordance with Clause 3.4.6a.


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e. `O' Rings shall conform to DEF STAN 02�337 Parts 1 to 3. The material shall befluorocarbon and the dimensions of `O' Ring housing recesses shall conform toBS 4518.

3.4.7 Rudder Stops

a. Mechanical Rudder stops shall be fitted at 37�.

3.4.8 Pipework

a. All pipework shall conform to the requirements of DEF STAN 02�797 Part 1.

3.4.9 Valves and Cocks

a. Where required, Valves shall be in accordance with DEF STAN 02�360 whereverpossible.

3.4.10 Ball and Roller Bearings

a. Ball and Roller Bearings shall be to metric dimensions and shall conform toBR 3026.

b. Hydraulic pumps that contain rolling element bearings shall not be used (ifapplicable).

3.4.11 Noise, Shock and Vibration

a. All equipment shall be designed to meet the requirements for airborne noise,shock and vibration as defined in DEF STAN 07�254 Part 2,DEF STAN 08�118 Part 1, BR 3021(1), BR 3021(2), BR 8470, BR 8471, BR 8472and BR 8473 as applicable. The noise and vibration reduction targets in anyShip shall be stated in the SRD.

b. All possible noise and vibration transmission paths shall be considered toenable noise shorts to be eliminated.

c. Equipment in the tiller flat in HM Surface Ships is subjected to high vibrationlevels at high Ship speeds and while going astern. The higher vibration levelsthat shall be required to be met will be included in the SRD.

3.4.12 Electromagnetic Compatibility

a. Electrical equipment shall be designed to meet the ElectromagneticCompatibility requirements of DEF STAN 59�41 Parts 2, 3, 4 and 7.

3.4.13 Nuclear Hardening

a. All components used in the Steering and Stabilizer System(s) control circuitsshall be hardened against Electromagnetic Pulse and Initial Nuclear Radiationas specified in DEF STAN 08�107.

3.5 Lubrication

a. Hull Bearings and other external bearings shall be water lubricated to complywith the requirements of MARPOL 73/78. See Section 2. However, otherlubrication mediums may be considered for use if it can be demonstrated thatthey meet or exceed the requirements of this Standard and MARPOL 73/78.


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b. A Lubrication System for Rudder and Stabilizer internal parts shall be providedas required. The Lubrication System shall be automatic in operation andcapable of delivering sufficient quantities to meet all operational conditions.

c. Requirements for oils and greases to be used for any purpose shall, whereverpossible, to be selected from those listed in DEF STAN 01�5. If this is notpossible it shall be brought to the attention of the Principle Contracts Officer(PCO) and/or the Design Authority, as applicable.

3.6 Safety

a. Assemblies or components which require to be lifted to aid maintenance andrepair shall be fitted with suitable means of lifting equipment, e.g. tapped holesfor eyebolts or permanent lifting lugs. (See Section 2).

3.7 Castings

a. Ferrous and Non�ferrous castings shall be in accordance withDEF STAN 02�745 Part 2 and DEF STAN 02�863.

3.8 Welding

a. Guidance on general welding requirements is contained in DGS/PS 9023.

3.9 Marker Plates

a. Equipment shall be provided with Marker Plates engraved with operatinginstructions and necessary diagrams. The plates shall be of a material notsusceptible to corrosion and shall be mounted in a well illuminated position on,or adjacent to, the equipment when installed.

b. Marker Plates, Identification Plates and Modification Plates shall be inaccordance with the requirements of DEF STAN 02�723.

3.10 Preservation and Maintenance

3.10.1 General

a. For general cleaning and preservation of Steering and Stabilizer System(s)equipment, reference shall be made to DEF STAN 02�341 Part 1. For painting,reference shall be made to DEF STAN 07�251.

3.10.2 Maintenance in Stores

a. All equipment shall be kept in clean and dry conditions.

b. Annually from date of preservation, unpainted steelwork shall be cleaned downand represerved in accordance with DEF STAN 02�341 Part 1.

c. DPA shall identify any equipment which requires regular testing or checkingwhile in stores.

3.10.3 Maintenance on Board

a. Maintenance on�board shall be defined by the Prime Contractor in conjunctionwith the System Designer and shall address the following points:

(1) Rudder(s) and Stabilizer(s) Fin Bearings and otherwise unprotectedBearings, such as those fitted to the Actuators, shall be greased atintervals specified in the handbook;


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(2) Where fitted, Pumps shall be turned electrically if power is available. Ifpower is not available, Pumps shall be turned by hand on a fortnightlybasis;

(3) Fortnightly following the installation and testing programme, theRudder(s) and/or Stabilizers shall be tested. External bearings shall beadequately pre�wetted and the internal lubrication system shall be inoperation as required. The Rudder(s) and Stabilzer Fins shall be checkedto be clear of any obstructions and, if clear, moved through their fullworking travel;

(4) Monthly following the installation and testing programme, followingactions from (3) above, the Rudder(s) and/or Stabilizers shall be tested.External bearings shall be adequately pre�wetted and the internallubrication system shall be in operation as required. The Rudder(s) andStabilzer Fins shall be checked clear of any obstructions and, if clear,moved approximately 5� in either direction and returned to the 0�position using the Hand Operating arrangements;

(5) Arrangements shall be made to protect bare metal working parts fromdirt and dampness during the intervals between moving the equipment;

(6) Where utilised, Hydraulic Systems shall be flushed to specificationfollowing installation. Filters shall be changed as indicated by therespective Filter Condition Indicators;

(7) Where appropriate to ensure that the fluid meets the cleanliness standardand conforms to the manufacturers' specifications in all respects, thecondition of Hydraulic System Fluid shall be sampled and tested everyfour months.

3.10.4 Flexible Hoses

a. Protective packaging on flexible hoses shall be retained as long as possible.Where feasible, cages or boxes shall be built around them to protect them fromdamage from external sources between installation and Setting to Work (STW).

3.11 Testing, Installation Inspections and Setting to Work

3.11.1 General

a. Pre�trial inspections shall be carried out in accordance with DEF STAN 02�350.

3.11.2 Testing Requirements

a. Each self�contained unit or sub�system of the Steering and/or Stabilizer Systemshall satisfy the tests laid down in a Production Test Specification (PTS). Thisshall be a separate document from the Production Acceptance Specification(PAS) written and used in�house by the Manufacturer in the build of the unit.

b. The PTS shall be written by the Designer and agreed with DPA at thefinalization of the design stage. The PTS shall be prepared in accordance withDEF STAN 00�52.

c. An overall system test shall be conducted on the first off production ordevelopment system in accordance with the PAS. Type tests of equipment newto RN service shall be carried out where specified in the SRD.


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3.11.3 Pressure Testing

a. The requirements for pressure tests are as follows:

(1) The various parts of each installation which are subject to hydraulicworking pressure together with the corresponding items of spare gearshall be tested before leaving the Manufacturer's works and afterinstallation on board. The pressures to which parts of the system shall betested are given in DEF STAN 02�797 Part 1 with the exception ofpressure gauges. Pressure tests for parts not covered in this Standard areto be determined and agreed with MOD(PE) during development.

(2) After manufacture pressure gauges shall be pressure tested in accordancewith BS EN 837�1. Thereafter pressure tests shall be restricted to thelimits of full gauge pressure for accuracy testing only. Pressure gaugesshall be positively isolated from pump and system test pressures.

(3) Parts tested are to be clearly stamped or etched or, where special materialsare involved, painted by the Manufacturer with his identification marks,the test pressure and test date.

(4) The shop pressure tests are to be carried out after parts are completelymachined and prior to painting.

(5) The test pressure shall be maintained for periods of time adequate topermit a thorough inspection of all parts for leaks. For parts in which it isespecially important to ensure soundness, the test pressure shall bemaintained for at least 30 minutes. Certification that the pressure testshave proved satisfactory shall be produced.

3.11.4 Testing After Manufacture

a. Subsequent to manufacture and pressure tests but prior to shipboardinstallation, tests shall be carried out in the Manufacturer's workshops inaccordance with the PTS. The tests shall record the performance of eachsub�assembly.

3.11.5 Installation Inspections

a. System(s) installation inspections and tests shall be conducted by the DocksideTest Organization (DTO) during the building/refit phase to ensure thatequipments are correctly sited and that alignment of Rudder(s) and StabilizerFins with respect to the hull is in accordance with DPA approved drawings.

b. In addition to the requirements listed in DEF STAN 02�350, particularattention shall be paid to the following areas when preparing test forms:

(1) Access for operation of controls;

(2) Security, clarity and ease of monitoring of mechanical Rudder andStabilizer Fins position indications;

(3) Door and panel openings;

(4) Removal of equipment and sub�assemblies for repair and maintenance.

c. The installation of the equipment in Hydraulic Systems shall be in accordancewith the procedures specified in DEF STAN 02�324 Part 1.


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3.11.6 System Preliminary Tests and Setting to Work

a. System Preliminary Tests and STW shall be carried out by the Shipbuilder,Dockyard or Contractor, as necessary, in accordance with approveddocumentation produced by the Manufacturer. The equipment shall operatewithin the requirements of Drawings and Production AcceptanceSpecifications approved by DPA.

b. Certification of satisfactory completion of STW by a contractor is required,together with a report listing any outstanding defects after the following tests:

(1) To check Rudder and Stabilizer Fin hull clearances, including mechanicalstops, as specified to allow full travel;

(2) To check the actual Rudder and Stabilizer Fin angle(s) against thoseindicated on the mechanical indicators;

(3) To check Rudder and Stabilizer Fin centering and locking arrangements;

(4) To confirm that the Ventilation System supplying relevant compartmentsand equipment are complete and available for use;

(5) To confirm that all operational and maintenance communicationfacilities associated with the system are satisfactory;

(6) Continuity checks on all cable cores and screens;

(7) Insulation Resistance�Continuity of all cables. Insulation Resistancetesting shall be carried out after removal of individual electronicsub�units or plugs and sockets;

(8) To confirm that the Conditioning Heater supplies are available andconnected correctly;

(9) To check power supply voltage and frequency levels;

(10) Operational checks on Motors;

(11) Initial runs of power units;

(12) Check Rudder and Stabilizer Fin direction, zero and maximum angles.

3.12 Trials

3.12.1 General

a. Trials of machinery and equipment shall be arranged and conducted inaccordance with DEF STAN 02�32, DEF STAN 02�350, DEF STAN 02�351,DEF STAN 02�352, DEF STAN 02�353 and DEF STAN 02�354.


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3.12.2 Preliminary Basin Trials

a. On completion of STW, detailed testing of the Steering and Stabilizer Systemsshall be carried out to satisfy the Project Manager/Equipment SupportManager (PM/ESM) to ensure the correct functioning of equipmentcomponents and systems, including remote and local controls. An AuthorisedRepresentative may be requested to witness any processes. The Trials shall beconducted by the Shipbuilder using his DTO and shall be a pre�requisite for theBasin Trial (DEF STAN 02�351 refers). Specific Tests and Checks shallincluded the following:

(1) Check of internal power supplies;

(2) Check of all Steering Control outputs at each Steering Position;

(3) System tests to check correct operation of all indications and alarms;

(4) Tests to check the accuracy and hysteresis of mechanical and electricalindication;

(5) Tests to confirm the correct operation and settings of Rudder andStabilizer Fin limit devices;

(6) Test to determine the settings of safety and pressure relief valves (ifapplicable);

(7) Tests to determine Actuator pressures (if applicable);

(8) Checks of Hydraulic Fluid temperatures at each Pump and Tank (ifapplicable);

(9) Checks to determine the starting and no�load currents of Motors;

(10) System tests to confirm Rudder and Stabilizer Fin positional accuracy;

(11) System tests to confirm that Rudder and Stabilizer Fin Servo ControlLoops have been correctly tuned to provide the required responsecharacteristics to step inputs;

(12) Tests to check Rudder and Stabilizer Fin rates;

(13) Checks of Rudder(s) response in Autopilot control with simulated Ship'shead and log inputs;

(14) Two hour endurance runs, with Rudder(s) and Stabilizer Fins operatedthrough their full travel and control of Rudder(s) demonstrated from allSteering Positions, operating the Steering and Stabilizer Systems tosimulate operational use as far as possible.

b. Unless otherwise specified, a trial of the Steering and Stabilizer Systems andequipment shall be carried out, in accordance with DEF STAN 07�254 Part 2and DEF STAN 08�118 Part 1, to determine the following:

(1) The airborne noise generated within the compartment;

(2) The vibration of each Motor and Pump both above and below the resilientmounting, if fitted;

(3) Underwater noise shall be determined by means of an over�the�sidehydrophone and in accordance with noise testing policy for the wholeShip.


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3.12.3 Basin Trials

a. In addition to the requirements contained in DEF STAN 02�351, the followingclauses detail the requirements for Steering Systems. In all cases thesponsoring authority is Warship Support Agency/Maritime CommissioningTrials and Assessment (WSA/MCTA), Machinery Trials and Assessment Unit(MTAU), who will be responsible for the conduct of all trials in Clauses 3.12.3b.to 3.12.3i.

b. The following trials shall be conducted on all vessels after Basin Trials and priorto Contractors Sea Trials (CST):

(1) Confirm the correct operation of the system in all modes of operation;

(2) Check that the position of the Rudder(s) and all associated indicationsagree with that demanded from all Steering Positions through the wholerange of operation, both increasing and decreasing Rudder angles;

(3) Check that the Rudder(s) can be moved and centralised using the HandPump.

c. The MTAU Trials Officer will require assistance from the PM/ESM AuthorisedRepresentative, the Shipbuilder and in some cases the Manufacturer.

d. The MTAU Trials Officer, in association with the PM/ESM AuthorisedRepresentative, will accept the system on behalf of DPA subsequent toevaluation of trials data. Any system or equipment may be rejected orconditionally accepted if it fails to perform within set limits of tolerance.

e. Representatives from both the Hydraulic (if applicable) and ControlsManufacturers shall attend the Basin Trial.

f. All trials forms required for conducting and recording the tests shall beproduced by the DTO, in association with the PM/ESM AuthorisedRepresentative, based on the following documentation:

(1) The Build Specification of the vessel;

(2) The SRD for the Steering System;

(3) Drawings, and the Steering System Manufacturer's requirements.

g. The Shipbuilder/Dockyard shall provide all necessary communications,electrical supplies, temporary recording equipment and cabling requested bythe MTAU Trials Officer.

h. Documentation required under Clause 3.7.5b. to confirm satisfactorycompletion of Preliminary Tests and STW shall be presented to the MTAUTrials Officer prior to commencement of the trial.

i. The MTAU Trials Officer, in association with the PM/ESM AuthorisedRepresentative, shall be responsible for compiling trials data/reports andsystem defect lists whether or not they result in degraded performance.


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3.12.4 Contractors Sea Trials

a. In addition to the requirements contained in DEF STAN 02�352, the followingclauses detail the trials requirements for Steering Systems during CST.

b. The following trials shall be conducted on all Ships of the Class during CST:

(1) Check the performance of the Steering System equipment under allmodes of operation, and from all Steering Positions;

(2) Check correct operation of the Autopilot;

(3) Monitor Hydraulic Fluid temperatures to confirm adequacy of coolingarrangements;

(4) Measure full load currents of Motors.

c. The MTAU Trials Officer, in association with the PM/ESM AuthorisedRepresentative, shall conduct the trials.

d. The MTAU Trials Officer, in association with the PM/ESM AuthorisedRepresentative, will accept the system on behalf of DPA subject to subsequentevaluation of trials data. Any system or equipment may be rejected orconditionally accepted if it fails to meet the contract specification.

e. Representatives from both Hydraulic and Control Manufacturers shall attendthe CST.

f. All trials forms required for conducting and recording the trials shall beproduced by the DTO, in association with the PM/ESM AuthorisedRepresentative.

g. The Shipbuilder/Dockyard shall provide all the necessary communications,electrical supplies, temporary recording equipment and cabling requested bythe MTAU Trials Officer in association with the PM/ESM AuthorisedRepresentative.

h. The following conditions shall apply when carrying out the trial:

(1) Frequent and varying changes to the vessel's speed and course;

(2) The vessel should be steered in hand control for initial trials;

(3) When satisfied with the general behavior of the Steering System, theAutopilot should be engaged and operated for a sufficient period atvarying speeds and courses to demonstrate its reliability and accuracy.

i. The MTAU Trials Officer, in association with the PM/ESM AuthorisedRepresentative, will be responsible for compiling the trials data/reports andreporting any specific equipment or system performance which fails to meet therequired specification and tolerance.

3.12.5 Final Machinery Demonstration

a. Following the Third Machinery Inspection and any necessary repairs, a FinalMachinery Trial and Final Machinery Demonstration shall be completed inaccordance with DEF STAN 02�354.

b. On completion, the Trials Officer shall confirm in writing to the CommodoreNaval Ship Acceptance (CNSA), that a satisfactory demonstration has takenplace.


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c. In First of Class or First of Batch vessels with a new type of Steering and/orStabilizer System, additional trials shall be conducted to allow the AutomaticSystem(s) to be tuned to give optimum performance. These trials shall becarried out by the System Designer and are the responsibility of the PrimeContractor for the vessel. Ideally, these trials should be carried out during CSTand prior to the conduct of the System(s) Acceptance Trial(s). In any event, alltrials on the System(s) shall, wherever possible, be complete before vessel'sacceptance date. If this is not possible, any incompleted testing and tuningtrials shall remain the responsibility of the prime Contractor untilsatisfactorily completed.

4. DESIGN REQUIREMENTS/GUIDANCE

Related Documents: DEF STAN 00�40 Parts 1, 2, 3, 4, 5, 6 and 8; DEF STAN 02�52;DEF STAN 02�109; DEF STAN 02�324 Part 1; DEF STAN 02�620; DEF STAN 08�107;DEF STAN 08�123; DEF STAN 59�36; see also Annex ANNEX A.

4.1 Design Parameters

4.1.1 General

a. Overall System Design shall embody advances in design concept and newdevelopments in technology, which may lead to innovative and alternativeproposals or solutions. This may include, but is not to be limited to, systemsutilising Electric Actuation of Hydrodynamic Control Surfaces, either direct orindirect, or other suitable, practicable means.

4.1.2 Fundamental Requirements

a. The fundamental requirements for Steering and Stabilizer Systems shall bederived from the Naval Staff Requirement (NSR) and the followinginformation given in the SRD:

(1) A statement of the required Steering and Stabilizer performance:

(a) Steering: Maximum range of angular Rudder movement,maximum speed of movement and accuracy and the maximumtorque to move the Rudder through this range at any Ship's speed(or a statement of the Manoeuvring performance required using theRudder(s) if the Rudder design shall be carried out by the SteeringSystem Designer);

(b) Stabilizer: Specified roll angle, which shall not be exceeded by morethan a given percentage of rolls in a stated wave spectrum, at aspecified Ship's speed and heading. The Stabilizer System shallremain fully operational when subjected to the maximumconditions of listing, rolling, trim or pitching as stated inDEF STAN 08�123;

(2) The modes of operation that shall be available from the system;

(3) The siting of control functions required;

(4) Maximum continuous period of operation and the Availability andReliability required;

(5) The frequency and duration of refit periods and maintenance periods;

(6) Power supplies available and details of any interfaces required with othersystems;

(7) Methods of control (e.g. local or remote).


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b. In larger vessels (Frigates and above), there shall be three Steering Positions asfollows:

(1) Primary Steering Position (PSP) - Bridge;

(2) Secondary Steering Position (SSP) - At a convenient location,displaced from the Bridge;

(3) Emergency Steering Position (ESP) - Steering Gear Compartment.

c. Consideration should be given to siting the SSP in the vicinity of the SteeringGear Compartment or near the centre line of the Ship.

NOTE Where arrangements dictate, there may be two separate ESP. TheChange�over Switch (COS) which selects Primary or Secondarycontrol by direct switching of circuits shall be arranged at the lowercontrol level, i.e. the SSP. Additionally, a suitable COS shall beprovided in the Steering Gear Compartment to disable RemoteSteering when under ESP control. In smaller vessels the SSP may beomitted with secondary control being switched directly to the ESP viasuitable COS in the Steering Gear Compartment.

4.1.3 Stabilizer System Aims and Concepts

a. Stabilization of the vessel shall be achieved by means of Stabilizer Finsprojecting from each side of the hull. The Stabilizer Control System senses therolling motion of the vessel and causes the Stabilizer Fins to tilt so that the liftforces, generated by virtue of the vessels forward speed, damp the roll motion ofthe vessel.

b. The roll angle is sensed by roll motion sensors, e.g. the vessels gyro from which aroll angle signal is transmitted to the Stabilzer Control System. Alternatively adedicated roll motion sensor can be installed as part of the control system. Atypical controller being a Proportional Integral Derivation algorithm but othertechniques may be used. Means of tuning the system during sea trials shall beincorporated into the the design.

c. The Stabilizer Control System varies the overall gain of the fin angle demandsignal according to the vessels speed and also limits maximum fin angledemands above a certain speed, according to an inverse speed squared law, inorder to protect the Stabilizer Fin Units from excessive loading at high speed.Additional Stabilizer Fin angle limitations may be required, additionalrequirements being detailed in the SRD.

d. Stabilizer System:

(1) In many vessels the system may comprise of more than one pair ofStabilizer Fins;

(2) Stabilizer Fin angle limitations, which may include a `quiet running'operational mode, shall be indicated in the SRD;

(3) If specified in the SRD, a method of controlling the amount of cavitationproduced by Stabilizer Fins shall be incorporated into the design, whichshall be capable of enduring up to Full Power Ahead or Astern withoutseriously diminishing the expected availability or life�span of theequipment.

(4) Methods of cavitation control may include air emission, the use of endfences or by other suitable approved means. Details of how it is proposedto control cavitation shall be produced within three months of the start ofcontract date and shall be forwarded to MOD(PE) for appraisal.


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4.1.4 Ship Characteristics

a. The following information shall be made available to the Steering andStabilizer Systems Designers by the vessel Designers:

(1) Common Items:

(a) Principal dimensions of Vessel;

(b) Range of displacement and associated metacentric heights insidewhich the Vessel is expected to operate;

(c) Maximum speed Ahead and Astern;

(d) Hull section offsets in way of the Rudder(s);

(e) Electrical Power Supplies;

(f) Ship's Speed Log interface data;

(g) MCAS system interface details;

(2) Steering:

(a) Number of Steering Positions;

(b) Number of Rudders, positions, maximum outreach, centre line andangle of Rudder Stocks and line flow at each position.

(c) Ship's heading Gyro Compass interface data;

(d) The vessel Designer or DPA may also specify the shape of eachRudder and the maximum torque and speed of operation requiredfor the Steering Gear;

(3) Stabilizer:

(a) Roll damping ratio over speed range;

(b) Number of Stabilizer Fins, positions, maximum outreach, lines ofthe Stabilizer Shafts and line flow at each position;

(c) Availability and details of roll motion sensor signals.

4.1.5 Data Transmission

a. Selection of the Data Transmission Mode within the Steering and StabilizerSystems shall be made at an early stage of development and will be defined inthe SRD.

b. Data transmission within the Steering and Stabilizer System(s) may beanalogue or digital and may employ electrical, fibre�optics, hydraulic, air orother means as required. Where Digital Data Transmission is used, theprotocols employed shall be fully defined at all levels in a separate ProtocolDocument.

c. Two separate lines shall be provided for each signal transmitted from one unitto another. One line shall be for the signal and the other line shall be for thereturn.

4.1.6 Environmental and Operational Conditions

a. If it becomes apparent during the development of the design that a significantweight or a cost saving could be achieved by acceptance of equipment to astandard lower than that specified, DPA shall be made aware of this, togetherwith any penalties (real or anticipated) in performance, reliability, support, etc.,which shall be identified and evaluated to the maximum possible extent.


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4.1.7 General Design Objectives

a. The following major features, in addition to the fundamental requirements,shall be considered in Steering and Stabilizer Systems:

(1) Upkeep Policy;

(2) Availability;

(3) Reliability;

(4) Maintainability;

(5) Vulnerability;

(6) Interchangeability;

(7) Economy of weight;

(8) Economy of space;

(9) Ease of operation;

(10) Noise and Vibration.

b. The SRD shall detail the relative importance of the above features dependantupon the vessel for which the systems are being designed.

c. An Availability, Reliability and Maintainability (AR&M) programme shall beconducted on the Steering and Stabilizer System(s) in accordance withDEF STAN 00�40 Parts 1, 2, 3, 4, 5, 6 and 8 as applicable.

4.1.8 Upkeep Policy

a. Upkeep Policy shall be agreed between the Prime Contractor and DPA at anearly stage of the design. In general, the policy shall be that of Upkeep byExchange.

b. Electronic equipment and sub�assemblies shall be designed to enable Ship'sStaff to carry out a policy of repair by replacement, down to Printed CircuitBoard or Card Level. The Upkeep Policy precludes the use of soldering ironsand the like and warrants minimum time for the diagnosis and replacement of adefective unit (order of five minutes). Consideration shall be given to minimizeindividual mounting of components and to group such components on readilyaccessible plug�in boards.

4.1.9 Availability

a. The equipment shall be designed for a life of at least 25 years, unless otherwisespecified in the SRD.

b. Mean Time Between Failure (MTBF) targets for `repairable at sea' and`non�repairable at sea' failures will be specified in the SRD. Separate figures forthe Rudder Operating Gear and the Control Systems may be set. A failure isnormally defined as follows:

(1) The inability of the Steering System(s) to operate the Rudder(s) underClosed Loop Control;

(2) Inability of one or more Stabilizing Systems to provide their designedStabilizing torque on the vessel.

c. Equipment availability targets will be specified in the SRD. The Mean Time ToRepair (MTTR) shall be calculated using this information and guidance given inDEF STAN 00�40 Parts 1, 2, 3, 4, 5, 6 and 8 as applicable. The systems shall bedesigned to achieve the MTTR. The availability of Hand Steering Control fromthe PSP shall achieve the maximum target given.


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4.1.10 Reliability

a. The equipment shall be designed with the highest possible reliability. Studiesshall be included to demonstrate that the MTBF targets have been met.

b. Equipment shall be designed to operate without the need for maintenance orrepair which would necessitate unscheduled Dry Docking of the vessel.

c. On failure of control equipment or loss of power supplies, the normal failuremode is for the Rudder(s)/Stabilizers to remain set in the final position.Provision shall be made for the Rudder(s)/Stabilizers to subsequently bereturned to and locked in the mid�position/zero angle, as detailed inClause 4.1.17b.

d. Rudders:

(1) The Control System for Primary and Secondary Positions shall bedesigned with two electrically independent control channels routedseparately throughout the vessel on Port and Starboard runs;

(2) At least two systems shall be provided to facilitate full control in the eventof failure of one system, albeit at reduced Rudder speed of movement.

4.1.11 Maintainability

a. Recommendations for the outfit of spares and special tools to be held on board,and spares to be held at shore establishments, shall be defined by the DesignAuthority. Guidance is contained in DEF STAN 02�52.

b. Maintainability shall be ensured by careful attention to detailed design,including the following:

(1) Parts shall be capable of replacement with minimum disruption to therest of the system, with no requirement to remove major items to replaceother components;

(2) Routine Planned Maintenance at the specified intervals;

(3) Withdrawal and maintenance envelopes shall be specified and agreed bySystem Designer and Shipbuilder early in the design;

(4) Provision of a Technical Manual containing details as specified in theSRD. See also Section 5.

c. A maintenance evaluation shall be conducted on all equipment(s) to prove themaintenance routines and to demonstrate that the above aims have been met.

d. Defective equipment shall be capable of being diagnosed, isolated and repairedor replaced without interfering with other Steering and/or StabilizerEquipment.

NOTE It is important to eliminate, wherever possible, a design arrangementwhich would permit one component failure to affect more than one setof equipment or more than one pair of Stabilizers in a multi setinstallation.

e. Equipment shall be designed with test points, test switches, meters and Built�inTest Equipment/Routines to enable simple overall system confidence checks tobe performed. Complex Control Equipments shall be provided with Built�inDiagnostic Equipment to indicate faulty items.

f. The design shall recognize the continuing need to reduce manning levels onboard vessels. Frequent operator checks or routines requiring a manual inputshall be avoided wherever practicable.


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4.1.12 Vulnerability

a. Action damage could result in the loss of Steering under the followingconditions:

(1) Control facilities at the Steering Positions are lost;

(2) Circuits connecting the Control Equipment to the Operating Gear arelost;

(3) The Main Electrical Power Supplies to the system are lost;

(4) The Operating Gear or Rudders are damaged.

b. Consideration shall therefore be given to the vulnerability of the various unitsin the Steering System(s). The overall System Design shall ensure that a singlefailure does not cause a complete loss of Steering.

c. Owing to the nature of the Ship's Stabilizer System(s), i.e. multiple units,reduced stabilisation may result from action damage causing failure of a singleunit. Consideration shall therefore be given to the vulnerability of all systemunits to ensure that the complete Stabilizing System is not immobilized by localdamage or a fire.

4.1.13 Interchangeability

a. The following general requirements shall be met:

(1) Equipment shall be interchangeable with equipment of the same designfitted in any other vessel;

(2) Jigs shall be used to ensure that the position of critical interfaces arewithin agreed tolerances and to ensure the interchangeability of allsimilar equipments.

b. The policy for individual assemblies is as follows:

(1) For the replacement of individual complete assemblies, e.g. Pumps andElectric Motors. The use of shims or liners is permitted to obtainalignment;

(2) Where technical considerations require fitted bolts to be used, clearinstructions regarding fitting limits shall be included on relevantdrawings;

(3) Where alignment of complete assemblies is maintained by spigoted joints,the faces and spigots shall be made to such tolerances as to ensuremaintenance of alignment without hand fitting;

(4) The requirements expressed in Clause 4.1.13a. also apply to completeassemblies specified as spare gear.

c. No machining or hand fitting shall be necessary for operational replacement ofsub�assemblies. Any components specified as Spare Gear, which requiremachining or fitting allowances, shall only be used with the approval of DPA.

4.1.14 Electronic Equipment Interchangeability

a. Electronic equipment shall, as far as possible, be modular in construction. Allassemblies shall be interchangeable down to the lowest replacement assembly.

4.1.15 Materials and Weight

a. Special consideration shall be applied when designing for systems which have alow magnetic requirement.


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b. When choosing materials, the Designer(s) shall consider the following:

(1) Previously used materials for major components, which are shown inTable 5.1;

(2) Alternative materials may be considered. However, their fire resistanceshall be suitable for the application, environmental conditions and anyassessed fire risk. The use of Aluminium is undesirable where prolongedcontact with sea water is possible due to susceptibility to corrosion.Where alternative materials are proposed, they shall be submitted to theDesign Authority for approval early in the design stage.

c. Within three months of the date of receiving the contract, or at such earlier dateas may be specified in the contract, the Prime Contractor shall provide theDesign Authority with a detailed list of the estimated weights. Thesepreliminary estimates shall be continuously reviewed and revised figuressupplied to the Design Authority. The grouping of items in these lists shallconform to the requirements of DEF STAN 02�109.

4.1.16 Economy of Space

a. The main considerations are as follows:

(1) The volume and siting of Steering Gear and associated systems andsupplies shall be carefully considered to optimize the use of compartmentspace;

(2) When designing equipment for minimum space and its location in acompartment, due account shall be taken of the withdrawal envelopes forcomponents, sub�assemblies and assemblies necessary to permitinspection, maintenance and repair by replacement. The effectiveutilization of space allotted for such purposes shall be checked on themachinery mock�up or model where this is available.

4.1.17 Ease of Operation

a. Simplicity of operation, under all lighting conditions is required and thearrangement of controls, levers, hand wheels, instruments and gauges shall bedesigned with this objective in view and for the minimum number of operatingpersonnel. The Designers' aim shall be to plan the controls such that nocondition of operation can be achieved other than that intended by theDesigner.

4.1.18 Emergency Hand Operation

a. Rudders:

(1) Emergency Hand Steering arrangements shall be mounted in a readilyaccessible position in the Steering Gear Compartment. See Clause 1.4;

(2) Investigations shall be conducted to establish the maximum time to meetthe stated requirements. If there is a requirement to operate theEmergency Hand Steering whilst going Astern, then performance targetsshall be stated;

NOTE This facility is not intended to provide a means of steering theship for more than a very short period of time whilst overcominga major emergency. Emergency Hand Operation should beconsidered as a means of centralising the Rudder(s) only.


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(3) Other requirements for emergency conditions are:

(a) The facility to mechanically lock the Rudder(s) amidships;

(b) Where more than one Rudder is fitted, it shall be possible to lockeach Rudder individually whilst still allowing use of the otherRudder.

b. Stabilizers:

(1) Readily accessible Emergency Hand Operating arrangements shall beprovided. In the absence of electrical power, these arrangements shall becapable of centralizing the Stabilizer Fins whilst the Ship is stopped in thewater. See Clause 1.4;

(2) Arrangements shall be provided to mechanically lock the Stabilizer Finsin the mid�position.

4.1.19 Software

a. All software incorporated in Steering and Stabilizer Systems shall be designedand documented in accordance with DEF STAN 02�620.

4.1.20 Electrical Equipment

a. Guidance on Design Requirements is contained in DEF STAN 08�107. Anyvariations shall be brought to the attention of the Equipment Sponsor forapproval.

4.1.21 Lubrication System(s)

a. The Lubrication System(s) shall be automatic in operation and be capable ofdelivering sufficient quantities to meet all operational conditions and anyRegulations Controlling Maritime Pollution; see Section 2.

b. Where Grease Lubrication is required, it shall be distributed by suitablepumping arrangements feeding to Lubrication Points through pipeworkincorporating flexible lengths. The System(s) shall allow metered quantities toLubrication Points, with each point being capable of isolation. LubricationPoints shall be specified by the overall System Designer, together with theLubrication requirements for each point. (See Clause 3.5). They should includethe following:

(1) Steering Systems:

(a) Rudder Bearings/Stocks;

(b) Actuator Bearings;

(2) Stabilizer System:

(a) Finshaft inner and outer Bearings;

(b) Actuator linkages, if fitted;

(c) Hull Gland rings.

c. Controls for any Automatic Lubrication Pump may be contained within MotorStarters where applicable and may, if necessary, include a timer.


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4.2 Steering Systems

4.2.1 System Partitioning

a. For the purpose of design, the overall Steering System shall be considered on afunctional basis as being made up of a number of interconnecting systems.More detailed descriptions are given in the following clauses.

b. The function of the Control System(s) and the Autopilot is to:

(1) Provide a manually driven Rudder Demand Signal;

(2) Convert Ship's head and speed into a signal of Rudder Angle Demand andtransmit them to the Rudder Operating System.

c. The Rudder Operating System comprises a number of units and sub�systems,whose function shall convert the Rudder Angle Demand into the requiredmovement of the Rudder(s). There will normally be at least two RudderOperating Systems.

d. The EPCMS shall provide the following functions to the Control System(s),Autopilot and Rudder Operating System(s):

(1) Power to drive the Operating System(s);

(2) Power supply to the Control Units;

(3) The means of starting up and shutting down the overall system;

(4) The Alarms, Warnings and Interlocks to protect the overall system;

(5) The system Running and Fault Indication.

4.2.2 Control System

a. The Control System shall comprise of at least the following:

(1) At the PSP:

(a) Autopilot;

(b) Hand Steering;

(c) Hand/Auto Change�over;

(d) Steering System Monitors;

(2) At the SSP:

(a) Hand Steering;

(b) PSP/SSP Change�over;

(3) At the ESP:

(a) Emergency Hand Steering control facilities.

4.2.3 Rudder Angle Indication

a. Visual mechanical indication of Rudder Angle shall be provided on each RudderUnit. This indication shall be visible from the ESP.

b. A Rudder Angle Indication System, independent from the Steering ControlSystem, shall be provided to allow indication at positions specified in the SRD.Normally these will be:

(1) PSP;

(2) SSP;

(3) Bridge Wings;


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(4) SCC;

(5) Operations Room;

(6) ESP;

(7) In addition, an indication signal may be required by some weapon(s)systems.

c. Where two Rudders are fitted, consideration shall be given to the need toprovide a Rudder Angle Transmitter on each Rudder to allow for Single RudderOperation.

4.2.4 Rudder Angle Feedback Transmitter

a. Duplicate and independent Rudder Angle Feedback Signals are required to eachcontrol system, which shall be obtained from separate Port and StarboardRudder Angle Feedback Transmitters.

b. Each Rudder Angle Feedback Transmitter shall be coupled to its own RudderUnit. The Transmitter Unit shall be designed so that it may easily be set at zero(i.e. zero output from its transducer) so that its output at other angles Port andStarboard can be checked to the design specification and adjusted if necessary.

c. The Transmitter Unit shall also be designed with regard to the environmentalconditions where it will be fitted. It shall be robust, watertight and resistant tooil ingress.

4.2.5 Navigation System

a. The following functions, independent from the Steering System, shall beprovided at the PSP and SSP:

(1) A Ship's heading indicator, which can be viewed by the helmsman whenoperating the Manual Steering Unit;

(2) A visual indicator of the angle of the Rudder(s).

b. The ESP shall be provided with the following functions:

(1) A visual indication of Ship's heading;

(2) A visual indication of Rudder Angle that does not involve electricaltransmission.

4.2.6 Hand Steering Units

a. A Hand Steering Unit (HSU) shall be fitted at the PSP and SSP to provideposition control of the Rudder(s) in a follow�up mode of operation. The unitshall be of an ergonomic design approved by DPA and wherever possible thePSP and SSP HSU shall be identical.

b. The HSU shall have a weatherhelm facility whereby it will automatically returnto a pre�set position when released by the helmsman. The pre�set positionshould be capable of being easily adjusted by the helmsman over a range of at

least ±10�. The Rudder demand shall remain fixed when the HSU is released bythe helmsman. Sufficient damping/friction shall be included in the HSU toensure that reasonable effort is required to operate it.

c. An illuminated scale, calibrated in one degree divisions, shall indicate theRudder Angle Demand.

d. Connections to the HSU shall be confined to power supplies for its own use,transmission of Rudder Angle Demand, control signals to and from theAutopilot and any essential indication/warning circuits.


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e. Duplicate transmissions of Rudder Angle Demand shall be provided, designatedPort and Starboard.

f. The following indications and controls shall be provided on the HSU or on aseparate panel/unit adjacent the HSU:

(1) A switch to select either Port or Starboard transmission circuits;

(2) A switch to select Hand Steering or Auto Steering;

(3) Indication of whether Hand Steering or Auto Steering is in operation;

(4) Indication of which Steering Position is in control;

(5) Indication of which Control Channel is in operation.

4.2.7 Test Facilities

a. External test points shall be provided for the connection of test equipment torecord the following functions, without affecting the normal operation of theAutopilot:

(1) Course error;

(2) Rudder demand;

(3) Other functions as specified, depending on the form of control equationsand the technology employed.

4.3 Autopilot

4.3.1 Definition of the Sub–System

a. Automatic operation of the Steering System shall be controlled by theAutopilot.

b. The Autopilot shall carry out the function of converting both course keepingand course changing requirements into a signal of Rudder Angle Demand. Inorder to fulfil this requirement it shall have separate course keeping and coursechanging modes.

4.3.2 Physical Characteristics

a. The Autopilot shall be a physically separate unit which can be removed from itshousing or cabinet without any consequent effect on any other part of theSteering System.

b. Autopilots shall be fitted at the Steering Positions specified in the SRD.

4.3.3 Inputs

a. Each Autopilot shall be provided with separate Compass Transmissions fromeach Transmitting Compass in the Ship's Navigation System.

b. Each Autopilot shall be provided with a Ship's speed input.

c. In some systems there may be a requirement for the Autopilot to accept aremote input of course to steer. If required this will be specified in the SRD.

4.3.4 Outputs

a. Each Autopilot shall provide an Output Rudder Angle Demand Signalcompatible with the remainder of the Steering Control System. Off�course andfailure alarm outputs shall be provided for indication at the Bridge/SCC.


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4.3.5 Ship Characteristics

a. In addition to the Ship Characteristics listed at Clause 4.1.3a., the followinginformation shall be made available to the Autopilot Designer by the ShipDesigner:

(1) Space allocation for Autopilot;

(2) Turning characteristics of the vessel based on model tests or calculations.

b. Where the Autopilot is being provided by a different supplier from theremainder of the Steering Control System, then details of the Steering ControlSystem and the interfaces between the Autopilot and Control System shall besupplied in addition to the details listed above.

4.3.6 Operator Displays and Controls

a. A continuous display of Set and Ship's Head shall be given. These shall be by anapproved analogue scale in order to allow a simple assessment of course error.

b. The operator shall be provided with a facility to control the rate of change ofcourse, a method of selecting the maximum Rudder Angle that can be applied bythe Autopilot and the means of selecting the number of steps available and themeans of implementation.

c. Illuminations of indications shall be controllable. They shall also to meet thenight adaptive illumination requirements specified for the vessel.

d. A means shall be provided for the operator to select an appropriate Ship's SpeedSignal to be fed to the Autopilot in the event of a failure of the signal from theShip's Log.

e. The control facilities available to the operator shall be agreed with DPA at theearliest possible stage of design. The system should automatically revert tohand control if an Autopilot failure is detected or if the hand steering unit ismoved to either Full Port or Full Starboard.

f. Arrangements shall be provided to prevent the normal Steering Control beingswitched from Hand Control to Autopilot unless the difference between Ship'sHead and course to steer is less than 5�.

g. A misalignment alarm shall be fitted to provide an audible and visual alarm inthe event of the set and achieved course being more than 5� apart.

4.3.7 System Testing

a. In order to adequately test the Autopilot, prior to installation, the Autopilotshall be assessed by the designer against a representative model derived fromdata provided by the Ship Designer. Sufficient tests shall be conducted toenable a full assessment of the Autopilot's performance against the abovespecifications to be carried out.

b. Harbour and Sea Trials shall be conducted in accordance with Clause 3.8.

4.3.8 Setting to Work

a. Suitable adjustments required for STW or tuning the Autopilot shall beprovided. These shall be in addition to the operator controls at Clauses 4.3.9a to4.3.9e and shall be accessible only when the unit is removed from its housing orit is mounted on an extension rack. Any adjustments provided shall be lockableor not subject to variation due to vibration.


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4.3.9 Test Facilities

a. External test points shall be provided for the connection of test equipment torecord the following functions:

(1) Course Error;

(2) Rudder Demand.

4.4 Stabilizing Systems

4.4.1 Stabilizer System Partitioning

a. For the purpose of design, the overall Stabilizer System shall be considered on afunctional basis as being made up of a number of interconnecting systems.More detailed descriptions are given in the following clauses.

b. The function of the Control System shall convert roll motion and Ship's speedinto an electrical signal of Stabilizer Fin Angle Demand and transmit the signalto the Stabilizer System(s).

c. The function of the Stabilizer System is to convert the Stabilizer Fin AngleDemand into the required movement of the Stabilizer Fin. There wouldnormally be at least one Port and one Starboard System.

d. The function of the Electrical Power and Supervisory System shall provide:

(1) Power Supplies to the System;

(2) The means to START and STOP the system;

(3) The alarms, warnings and interlocks to protect the system;

(4) System running and fault indications.

e. Power supplies shall be in accordance with Clause 3.3.1.

4.4.2 Control System

a. The Control System shall normally consist of a Stabilizer Central Control Unit(SCCU) which houses the circuits used to compute Stabilizer Fin AngleDemands, which, with the Stabilizer System(s), automatically stabilize theShip. The performance of the SCCU combined with that of othercomponents/systems of the Stabilizer System(s) shall meet the requirements ofthe relevant Sections of Clause 4.1.

b. The electronic circuits in the SCCU shall process the roll motion informationusing a suitable algorithm which should include a ship's speed term to providethe required fin angle demands to the Fin Servo Systems to stabilize the ship.The computations shall enable the stabilizer to operate automatically innormal duty without further operator adjustment.

c. The performance of the SCCU shall be such that when combined with that ofthe Stabilizer Systems the overall performance of the Stabilizer System meetsthe requirements of Clause 4.1.2 and Clause 4.1.10.


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d. The design of the SCCU is such that shall operate continuously, when seaconditions require, at a 100% duty cycle without excessive temperature rise.Components shall be suitable for the temperature within the enclosure, whendue allowances have been made for the compartment ambient temperature,and shall meet the requirements of DEF STAN 59�36.

e. The SCCU shall provide the following facilities:

(1) Maintenance of normal stabilization about a datum defined in the SRD;

(2) An automatic forced roll facility with adjustable roll amplitude andfrequency; the controls for which shall be readily accessible to theoperator and shall permit easy adjustment of amplitude and frequency ofroll;

(3) Manual setting of Ship's speed under fault conditions;

(4) A `quiet running mode' Stabilizer Fin Angle limitation will be defined inthe SRD;

(5) A method of aligning the Stabilizer Fin to the line of flow (Zero Fincondition);

(6) Comprehensive Built�in Test (BIT) and Fault Diagnosis Facilities, whichshall include a method of recording the following functions withoutaffecting the normal operation of the Stabilizers:

(a) Roll Angle;

(b) Stabilizer Fin Angle for each Stabilizer Unit;

(c) Stabilizer Fin Demand Angle for each Stabilizer Unit;

(7) Calibration facilities for Roll Angle and Ship's Speed.

4.4.3 Stabilizer Fin Angle Indication

a. Visual mechanical indication of the Stabilizer Fin Angle shall be provided oneach unit.

b. Provision shall be made for indication of individual Stabilizer Fin angles at theSCCU for maintenance or STW purposes. This can be made by means of aselectable meter or indicator or by a special purpose hand held unit capable ofbeing used without interfering with system operation.

4.5 Safety

a. Guards shall be fitted to protect personnel from moving parts such asActuators, Connecting Rods, Pump Drive Couplings, etc.

b. Arrangements for the safety of electrical equipment shall conform toDEF STAN 08�107 and where Hydraulic Equipment is fitted,DEF STAN 02�324 Part 1.


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5. CORPORATE EXPERIENCE & KNOWLEDGE

Related Documents: BS ISO 6194 Part 4; BS EN 10087;BS EN 10277 Parts 1, 2, 3, 4 and 5: BS EN 10278; BS 970 Part 1 and 2;BS 7780 Parts 1, 2 and 3; DEF STAN 02�324 Parts 1, 5 and 6; DEF STAN 02�706;DEF STAN 02�729 Parts 1 2, 3, 4 and 5; DEF STAN 02�769; DEF STAN 02�773;DEF STAN 02�780 Part 3; DEF STAN 02�849; DEF STAN 05�42; DEF STAN 07�244;DEF STAN 08�105; DEF STAN 59�36; DEF STAN 61�5 Parts 1 and 4; BR 2000(53)(2);DGS/PS 9023; see also Annex ANNEX A.

NOTE Section 5 does not include mandatory requirements; it should be lookedupon as how systems have been designed in the past.

5.1 Rudder and Stabilizer Fin Control

a. It is convenient to consider Rudder(s) and Stabilizer Fin Control separatelyfrom the Hydraulics and the Associated Power System. Rudder and StabilizerFin Control is dealt with in the following clauses of this section. The HydraulicSystem is covered by Clause 5.2.5 and the EPCMS is covered by Clause 3.3.

b. The Rudder Servo Amplifier (RSA) received a Rudder Angle Demand Signalfrom a HSU or Autopilot Unit. It also to receive a Rudder Feedback Signal fromthe Rudder Feedback Unit.

c. The SFLCU received a Stabilizer Fin Angle Demand Signal from the StabilizerControl System. It also received a Stabilizer Fin Feedback Signal from theStabilizer Fin Feedback Transmitter.

d. The RSA and SFLCU had provision for pre�setting the magnitude of thesesignals for scaling purposes or for initial setting up. These controls would not bereadily available to the operator.

e. The output stage was designed to eliminate parasitic high frequency oscillation,which was normally achieved by limiting the Amplifier Open Loop Gain at highfrequencies.

f. The output stage contained limiting circuits, preferably active, which limitedthe signal to a preset value. The error at which this limitation operated beingfixed at a value depending on the maximum speed of Rudder and/or StabilizerFin movement/speed required and on the characteristics of the HydraulicSystem.

g. Components for new equipment were designed and selected to keep variableresistors and other means of adjustment to a minimum. Any adjustment orvariable resistors used were connected such that failure of that device would atworst cause reduced performance of the Steering and/or Stabilizer System(s)and would not cause complete loss of Steering and/or Stabilization.

h. Ease of access was required to be provided for maintenance and setting up ofinstalled equipment.

i. `Select on test' components were not permitted to be used without permissionfrom the Design Authority.


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j. Test facilities at the RSA, when not sited in the proximity of the HSU, and theSFLCU included means to:

(1) Center the Rudder(s) and/or Stabilizer Fins to amidships/zero angle;

(2) Position the Rudder(s) and/or Stabilizer Fins to full angle or tointermediate angles.

k. Accessible test points, to facilitate system level maintenance and on�boardtesting, were provided for the purpose of measuring the following signals:

(1) Rudder(s) and/or Stabilizer Fins Angle Demand Signal;

(2) Rudder(s) and/or Stabilizer Fins Angle Feedback Signal;

(3) Error Signal;

(4) Control Valve Input Signal.

l. In addition to the above, test points were provided to enable fault diagnosis to beconducted down to the lowest replaceable assembly or major component.

5.2 Electro Hydraulic Type System

5.2.1 Rudder Servo System

a. Rudder Servo Systems have consisted of:

(1) Rudder Servo Amplifiers;

(2) Hydraulic Power Units (HPU) comprising Motor Driven HydraulicPumps (MDHP), Hand Pump, Fluid Tank, Servo Filters andElectro�hydraulic Control Valve;

(3) Rudder Actuators and Rudder Units, including Rudder Angle FeedbackTransmitters;

(4) Hydraulic Pump Motor Starters.

b. Items were interconnected to form a Closed Loop Position Control System forthe purpose of positioning the Rudder, in accordance with the Rudder AngleDemand Signal received from the Control System, to the required performance.

c. Overtravel Limit Switches were fitted to raise an alarm if the Steering Positionin control of the Rudder(s) moved 2� past the maximum designed angle.

d. The Rudder Feedback Transmitter returned a signal to the RSA, which wascompared with the Rudder Demand Signal. The output from the RSAcontrolled the Hydraulic Power Circuit to drive the Rudder Actuators inproportion to the demand. Any limited response was fully accounted for in theoverall system response.

e. Each RSA received a separate Rudder Demand Signal from the Control System(i.e. one Port, one Starboard). The Hydraulic Pumps being capable of beingoperated by either of the Servo Amplifiers, but not by both Servo Amplifiers atthe same time.

f. Each Rudder Servo Loop was self monitoring with a signal available from theRSA to indicate the status of the Rudder Servo Loop.

g. The components within the Rudder Servo Loop were designed and arrangedsuch that failure of any component would not result in damage to any othercomponent.


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5.2.2 Rudder Servo Amplifier

a. Two RSA were commonly used, one for each Control System. They were locatedat the SSP or in the Steering Gear Compartment and contained the followingfunctions:

(1) Power distribution to Rudder Demand System;

(2) Rudder Servo Fault Detection Circuits;

(3) Rudder Servo `in control' and `stand�by' change�over circuits;

(4) Rudder Servo Test and Monitor facilities.

b. Each RSA derived its power via the Main Electrical Distribution System.DEF STAN 61�5 Parts 1 and 4 applied for voltage tolerances, transientexcursions and other relevant parameters.

c. Low voltage and regulated power supplies required within the RSA werederived from the 60 Hz supply.

d. Selection of the non�controlling channel automatically turned the controllingchannel OFF.

5.2.3 Stabilizer Fin Servo System

a. The Stabilizer Fin Servo System(s) consisted of the following:

(1) SFLCU;

(2) HPU comprising a MDHP, Hand Pump, Fluid Tank, Electro�hydraulicControl Valve;

(3) Stabilizer Fin Actuator and Stabilizer Fin Unit, including a Stabilizer FinFeedback Transmitter (FFT);

(4) Hydraulic Pump Motor Starter.

NOTE In some installations the functions of the SFLCU were incorporated inthe Stabilizer Central Control Unit (SCCU).

b. Items were interconnected to form a Closed Loop Position Control System forthe purpose of positioning the Stabilizer Fin, in accordance with the StabilizerFin Angle Demand Signal received from the Control System, to theperformance required.

c. The FFT returned a signal to the SFLCU which compared it with the StabilizerFin Demand Signal. The output from the SFLCU controlled theElectro�hydraulic Control Valve so that the magnitude and direction of theHydraulic fluid flow to the Actuator was proportional to the demand from theSFLCU.

d. Each Stabilizer Fin Servo System operated completely independently of theother units.

e. The Stabilizer Fin Servo System was located and constructed to comply withthe requirements of this Standard and the relevant system SRD.


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5.2.4 Facilities of the Stabilizer Central Control Unit

a. The SCCU maintained normal stabilization about a natural list datum, i.e.about the ship's natural laden orientation, which might be a small angle to portor starboard of the true vertical depending on load, wind and sea.

b. Additional provision in the SCCU for stabilization about the true vertical, wasnot required unless specifically included in the SRD.

c. The SCCU would provide an automatic forced roll facility. It was readilyaccessible and would have easy to use operator controls which allowed theamplitude and frequency of the roll to be adjusted.

d. The SCCU contained electronic computation circuits to compute the requiredangle. The control algorithm used was unambiguous, and a simple means tochange essential constants in the algorithm during tuning at sea was provided.This could be implemented using digital or analogue electronics.

e. The initial settings for constants were derived after a computer evaluation ofthe overall system transfer function and performance for the particular ship.

f. In the event of failure of a ship's speed signal to the SCCU, an alternative meanswas provided for the ship's speed to be set manually. Selection was made by apre�set programme or switches or by using the fixed inputs described inClause 5.2.4m.

g. In addition to the speed dependent fin angle limitation described inClause 5.2.4, a further `Quiet Running' operational mode may have beenrequired, selected by a switch on the SCCU panel. The fin angle limitationsrequired for this mode of operation would be specified in the SRD.

h. The SCCU provided multiple fin angle demand outputs for operating all the finson the ship.

i. Means were provided to enable fin angle demand signal to be switched to a `ZeroFin' condition. The stabilizing signal was removed and replaced with aconnection that causes the fin to align to the line of flow (zero fin).

j. The SCCU contained built�in test and fault diagnosis facilities for majorassemblies. This may have been in the form of a test meter, operators switchesand fault diagnosis lamps or a hand�help test unit as required. A test diagnosiscard relating to the switch position and meter indications was provided, whichwas preferably located with the equipment.

k. Provision was made on an accessible panel within the SCCU or on eachassembly/printed circuit board for test points which enabled each lowestcomplete replaceable assembly and each critical component to be evaluated forits functioning.

l. If a processor was included in the SCCU it was provided with a self monitoringfacility and built in test equipment to allow easy fault diagnosis to board level.

m. For system test purposes the SCCU contained a calibration facility for both rollangle and ship speed, whereby fixed inputs corresponding to a specified rollangle and speed could be switched into circuit. The roll angle and ship speedmagnitudes were evenly spread over the allowable range.

n. All small electronic components were mounted on plug�in printed circuitboards. Edge connectors were not acceptable, and boards were fitted withappropriately sized plug and socket connectors, with gold plated contacts,selected from DEF STAN 59�36. The plug�in printed circuit boards had testpoints brought out to pins.


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o. The cabinet would preferably have had an outer panel carrying push�buttonsand lights comprising the minimum for operation of the equipment and had aninner panel for sensitivity, calibration and test switches used for setting towork, maintenance and fault diagnosis.

p. For the purpose of fault finding and maintenance, provision is was made forinternal illumination without the cabinet.

q. Indicating lamps are to be provided in the outer panel to display the Runningand Not Running state of each of the Port and Starboard fin motors. They are tobe readily visible. If the SCCU cannot be installed in the SCC, data from theouter control panel is to be relayed to the SCC and displayed on a dedicatedpanel unless the Statement of Technical Requirements calls for these functionsto be carried out by the MCAS system, in which case the interface details will bespecified by the Ship Design Authority.

5.2.4.1 Stabilizer Fin Local Control Unit

a. The SFLCU contained the necessary equipment to achieve the followingfunctions:

(1) Stabilizer Fin Servo System Test and Monitor Facilities;

(2) Stabilizer Fin Control in response to Stabilizer Fin Angle Demand andStabilizer Fin Feedback Signals;

(3) Fault Diagnosis facilities.

b. The SFLCU was located in the same compartment as the HPU, Stabilizer FinActuators and Stabilizer Fin Unit which it served.

c. The SFLCU derived its power from the 440 V 60 Hz power supply to itsassociated Motor Starter. DEF STAN 61�5 Parts 1 and 4 applied for voltagetolerances, transient excursions and other relevant parameters.

d. Low voltage and regulated power supplies required within the SFLCU werederived from the 60 Hz supply.

e. If 400 Hz was required for ac data transmission, it was derived internally in theSCCU or SFLCU unless it was only a reference for roll or speed signal inputs.

f. Referring to Clause 5 2.3.1a, it is convenient to consider Stabilizer Fin controlseparately from the Hydraulics and the associated Power System. Therequirements for Stabilizer Fin Control are dealt with in the Clause 5.1. TheHydraulic System is covered by Clause 5.2.4 and the Electric Power Control andMonitoring System is covered by Clause 3.3.

5.2.4.2 Stabilizer Fin Angle Feedback Transmitter

a. The Stabilizer Fin Angle Feedback Transmitter was coupled to the StabilizerFin Unit. The Transmitter Unit was designed to allow ease of setting at zero(i.e. zero output from its transducer) so that its output at other positive andnegative angles could be checked to the design specification and adjusted ifnecessary.

b. The Transmitter Unit was designed with regard to the environmentalconditions of where it was to be fitted and was designed to be robust, watertightand resistant to oil ingress.


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5.2.5 Steering and Stabilizer Hydraulic System

a. The Steering and Stabilizer Hydraulic System(s) contained at least twoHydraulic Power Packs, each capable of providing a supply of hydraulic powerto either or both Systems on receipt of a signal from either the RSA or SFLCU.Hydraulic Fluid OX40 (HS200X) was used unless otherwise specified in theSRD. Overall system design was in accordance with DEF STAN 02�324 Parts 5and 6.

b. The Hydraulic System was capable of providing an adequate supply ofhydraulic fluid under all operating conditions, such that the Steering andStabilizer System(s) Actuators were capable of sustaining the required rate ofoperation to meet the specified time of hardover�to�hardover.

NOTE The required time was calculated by the Prime Contractor for theoptimum Stabilizer Fin performance to be achieved. The design timesformed an important part of overall Ship performance, being notifiedat an early stage as part of the Tender Response.

c. A typical Steering and Stabilizer Hydraulic System comprised of the followingequipments:

(1) Hydraulic Power Unit(s) complete with means to vary the flow rate to theActuators in response to the electrical signals;

(2) Steering and Stabilizer Actuators, Rotary or Linear, one set on eachRudder and Stabilizer Fin;

(3) Locking Valve(s);

(4) Hydraulic Fluid Heat Exchanger (if required);

(5) Dedicated Hydraulic Fluid Reservoir for each pump, or alternatively acommon reservoir with dividing weir(s);

(6) Pipework as required incorporating Flexible Hoses;

(7) Hand Pump;

(8) Hydraulic noise attenuators to achieve the specified noise performancelevels (if required).

NOTE Rudders were mechanically linked. They were also capable of operating insingle mode (i.e. one Rudder only) with the other, mechanically locked,amidships, with its actuator isolated from the Hydraulic System. A facilityfor locking both Rudders amidships during extended harbour periods wasalso provided.

5.2.6 Hydraulic Pumps and Controls

a. Hydraulic Pump Units were of a constant speed and capable of continuousoperation. They were of any standard type, although innovative designs may besubmitted to DPA for prior approval. In addition to environmentalrequirements, the following features were considered when designing thesystem:

(1) A Boost Pump to supply servo control pressure, and replenishment boostpressure to the Main Hydraulic Circuit to avoid cavitation and toreplenish any fluid losses. The Charge Pump could be driven direct by themain pump drive shaft;


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(2) The arrangements fitted to the Hydraulic System for controlling fluidflow rate and direction were of a proven and reliable type/design;

(3) The need to use a pump with integral cross�line relief valves;

(4) A Control and Monitoring System to form part of a logical system capableof recognizing, identifying and isolating a single failure fluid loss in theHydraulic Systems. Associated warnings and alarms were provided,normally in the SCC;

(5) Provision was made for the Motor(s) to be stopped automatically should afluid low level alarm occur in the Stabilizer System.

b. Unless otherwise specified, provision was made to enable the pumping unit tobe rotated by hand without disconnecting any part.

5.2.7 Actuators

a. Actuators were of linear or rotary type, which convert high pressure fluid into atorque at the cross�head shafts. If linear actuators were specified, they weresecured to a substantial bedplate forming part of the Ship's structure.See DEF STAN 02-324 Part 1.

b. The Actuator on each Rudder was capable of operating both Rudders togethervia the mechanical link; the other Actuator having been put into a bypasscondition.

c. Positive mechanical stops were fitted to limit the angle of Rudder and StabilizerFin movement to the maximum Rudder and/or Stabilizer Fin operating angleplus 2 degrees.

d. Each Actuator was provided with the following for flushing, sampling andcharging purposes:

(1) An approved self�sealing coupling, fitted at the bottom of the unit at thefurthest point from the fluid inlet;

(2) An air venting connection, fitted at the highest point of the system.

5.2.8 Heat Exchangers

a. Where required, and unless otherwise specified, Heat Exchangers were seawater cooled in accordance with DEF STAN 08�105. Maximum coolanttemperatures were stipulated in the SRD.

5.2.9 Hydraulic Fluid Reservoirs

a. Bulk storage of Hydraulic Fluid was arranged in accordance withDEF STAN 02�324 Part 1.

b. A local storage tank was provided for Hydraulic Fluid, sited so that it could rundown by gravity to the Hydraulic Fluid Reservoirs. Its capacity was at leasttwice that of both reservoirs:

(1) Rudders:

(a) Separate header tanks for each Hydraulic Power Unit wereconnected to suit the requirements of the Hydraulic System.However, they were arranged such that damage to either one (or itsassociated pipework) would not cause loss of both Units.


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(2) Stabilizers:

(a) Local reservoirs were connected to suit the requirements of theHydraulic System. However, they were provided with a means ofisolation under damage conditions.

5.2.10 Hydraulic System Cleanliness

a. The design included flushing arrangements, as defined in DEF STAN 02�324Part 1.

b. Filtration arrangements met the requirements of DEF STAN 02�324 Part 1.

c. Cleanliness standards for Hydraulic Systems was decided by the SystemDesigner, taking due regard of the components to be used. System standardswere stated in the Tender Response and not changed without prior agreementwith DPA. Particulate contamination classes for fluids in Hydraulic Systemsare defined in DEF STAN 05�42.

5.2.11 Relief Valve Arrangement

a. The Hydraulic System was protected from over pressure conditions by PressureRelief Valves, arranged in a crossed line configuration, i.e. either line to becapable of relieving the other in the event of an excess pressure conditionarising. The valves operating at 10 per cent above WP and were capable ofrelieving full system flow.

b. Relief Valves were fitted on the delivery side integral with or adjacent to theHydraulic Pump(s) to relieve the pressures specified in the SRD. No othervalves were fitted between Pump(s) and Relief Valves.

5.2.12 Pipework

a. All Hydraulic System pipework was designed in accordance withDEF STAN 02�324 Part 1.

5.2.13 Valves and Cocks

a. Cocks that had direct metal to metal contact between body and plug, whetherlubricated or not, were used only where the static head is less than 0.7 Bar, e.g.in the suction lines between fluid reservoirs and hydraulic pumps.

5.2.14 Filtration

a. Filters were installed in accordance with DEF STAN 02�324 Part 1 and asconsidered necessary by the System Designer.

b. A suitable filtration rig was always used when filling or topping up a HydraulicSystem. See BR 2000(53)(2).

5.2.15 Hand Pump

a. A hand pump was fitted to each Hydraulic System, capable of moving theRudder(s) when the Ship is underway and a single Stabilizer Fin at zero Ship'sspeed. The Hand Pump was capable of operation by not more than two persons.See Clauses 1.4 and 4.1.18.


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a. Each Motor was to be capable of developing the maximum Full Load Torqueimposed by the pump under all duty cycle conditions for a period of one hour.

b. Each Motor was capable of developing not less than 120 per cent of full loadtorque on starting, or developing the maximum torque to start and acceleratethe pump under the most severe conditions, whichever is the greater. Themotor reaching full speed within 10 seconds after being switched ON, inaccordance with DEF STAN 07�244.

5.2.17 Pump Drive Couplings

a. Flexible Couplings, of an approved design, were fitted between the ElectricMotors and Hydraulic Pumps, which were capable of accommodating minormisalignment.

5.2.18 Seals

a. Seals for hydraulic pump shafts were of the rotary shaft lip type which was inaccordance with BS 7780 Parts 1 to 3 and BS ISO 6194 Part 4 (whereapplicable).

5.2.19 Materials

NOTE Electro�hydraulic Equipment for use on Ships where a Low MagneticSignature is required, e.g. Single Role Minehunters and MineCountermeasure Vessels, were manufactured from non�magneticmaterials.


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Component Material Specification

Linear Actuator Piston Rod;Cylinders and Pins;Rotary Actuator rotor and stator;Distribution manifold;Rudder locking valve block.

Forged Steel Proposed by the PrimeContractor and submittedto DPA for approval

Rudder Stock Cross�HeadConnecting Rod;Rudder Stock overlay in wayBearing Journals.

Forged Steel withStellite 306 N overlay or asapproved by DPA

Proposed by the PrimeContractor and submittedto DPA for approval

Rudder Stock and Hull Glands. Mechanical Seals orTraditional Glands

As approved by DPA

Rudder(s). Cast Steel and Steel Plate DEF STAN 02�849

Baseplate;Mechanical Linkages.

Steel As required to meet Shipstandards

Fluid Reservoirs. Stainless Steel BS 970 Parts 1 and 2, BS EN 10087, BS EN10277 Parts 1 to 5 and BS EN 10278

Bearings:Rudder Stock (in�board andoutboard);Rudder Stock Thrust RingsPintle.

Mild Steel with Stellite facing;Phenolic Resin bearings maybe used in smaller Ships whereapproved by DPA

Stellite 306 N facing

Piping (Rigid);Piping (flexible).

70/30 Copper Nickel;Reinforced Rubber

DEF STAN 02�780 Part 3;DEF STAN 02�324 Parts 5and 6

Welding:Machinery;Structures;Consumables;Acceptance Standards;Non�destructive Examination.

DGS/PS 9023DEF STAN 02�706DEF STAN 02�769DEF STAN 02�773DEF STAN 02�729Parts 1 to 5 as applicable

Table 5.1 – Previously used Materials and Welding Guidance

5.3 System Manuals

5.3.1 Typical Contents

a. Manuals for Systems contained the following details:

(1) Illustrated and detailed descriptions of the overall system and itssub�systems;

(2) Illustrated and detailed descriptions of the units, sub�assemblies andcomponents in the sub�systems;

(3) General, functional and operational description of the Steering orStabilizer System;

(4) Operating Instructions;

(5) Hydraulic system cleaning and flushing procedures;


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(6) Maintenance Procedures;

(7) Fault Finding;

(8) Installation Instructions;

(9) STW.

5.4 System Preliminary Tests

a. The DTO was responsible for the production of all test documentation to certifythat the Hydraulic System(s) had been installed and connected correctly. Thetest documentation covered the following tests:

(1) To fill and vent Hydraulic Systems;

(2) To pressure test Hydraulic Systems;

(3) To confirm that the Hydraulic System had been cleaned and flushed to thelevel of cleanliness required after pressure testing;

(4) To demonstrate Hand Pump operation;

(5) To ascertain that any cooling services associated with the HydraulicEquipment were complete and available for use;

(6) To prove correct operation of Power Units, Servo, Regulating and ReliefValves;

b. Documentation covering the above tests was required to be submitted to MODOverseers or QA organization for approval.


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ANNEX A.A.

RELATED DOCUMENTS

ANNEX A1. The following documents and publications are referred to in this Standard:

MARPOL 73/78 International Convention for the Prevention of Pollution fromShips

LOLER 1998 Lifting Operations and Lifting Equipment Regulations (1998)

BS ISO 6194 Rotary shaft lip type seals:

Part 4: Performance Test Procedures

BS EN 837�1 Specification for Bourdon Tube pressure and vacuum gauges

BS EN 10087 Free cutting steels. Technical delivery conditions forsemi-finished products, hot rolled bars and rods

BS EN 10277 Bright steel products. Technical delivery conditions:

Part 1: General;

Part 2: Steels for general engineering purposes;

Part 3: Free cutting steels;

Part 4: Case�hardening steels;

Part 5: Steels for quenching and tempering

BS EN 10278 Dimensions and tolerances of bright steel products

BS 970 Specification for wrought steels for mechanical and alliedengineering purposes:

Part 1: General inspection and testing procedures and specific requirements for carbon, carbon manganese, alloy and stainless steels;

Part 2: Requirements for steels for the manufacture of hot formed springs

BS 4518 Specification for metric dimension of toroidal sealing (`O') ringsand their housings

BS 7780 Specification for rotary shaft lip type seals:

Part 1: Nominal dimensions and tolerances;

Part 2: Vocabulary;

Part 3: Storage, handling and installation

JSP 430 Ship Safety Management System Handbook:

Volume 1: Policy and Guidance on MOD Ship and EquipmentSafety Management


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DEF STAN 00�40 Reliability and maintainability:

Part 1: Management responsibilities and requirements forprogrammes and plans;

Part 2: General application guidance on the use of Part 1;

Part 3: Application of national R and M documents;

Part 4: Guidance for writing NATO R and M requirementsdocuments;

Part 5: Guidance on R and M training;

Part 6: In�service R and M;

Part 8: Procurement of off�the�shelf equipment

DEF STAN 00�52 General requirements for product acceptance and maintenancetest specifications and test schedules

DEF STAN 01�5 Fuels, lubricants and associated products

DEF STAN 02�32(NES 32)

Requirements for Arrangements and Conducting Inspections andTrials During the Construction and Conversion of HM SurfaceShips


Requirements for the Preparation of Ship System and EquipmentList (SS&E List)(Obsolescent, to be incorporated into NES 48 Part 3)


Stability Standards for HM Surface Ships


Requirements for Hydraulic Systems:

Part 1: General;

Part 5: Flexible Hose, Multiple Spiral Wire Reinforced RubberHose Assemblies;

Part 6: Flexible Hose, 2 Layer Wire Braid Reinforced RubberHose Assemblies


Requirements for Elastomeric Tordial Sealing Rings (`O' Rings):

Part 1: General and Surface Finish Standards Relative to Manufacturer;

Part 2: List of Preferred Elastomeric Toroidal Sealing Rings;

Part 3: Anti�Extrusion Rings (Back Up Rings)


Requirements for Cleaning of Items, Components and Equipmentfor Fluid Systems:

Part 1: Cleaning


Guidance for the Pre�Trial Inspections of MachineryCompartments and Installations in HM Surface Ships


Requirements for First Machinery Inspections and Official BasinTrial of Propulsion Machinery in HM Surface Ships


Secondary Machinery Inspections and Contractors Sea Trial ofPropulsion Machinery in HM Surface Ships


Examination of machinery in HM Surface Ships on Completion ofContractors Sea Trials


Third Machinery Inspection, Final Machinery Trial andDemonstration of Propulsion machinery in HM Surface Ships


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List of Preferred Standard Valves (Metric) (Low Pressure)


Guide to Cable Entry, Termination and Junction Components forEquipment


Requirements for Software for use with Digital Processors(to be withdrawn on the publication of ISSI42)


Requirements for General Application to Rotating ElectricalMachinery


Requirements for ac and dc Starting and Control Gear


Welding and Fabrication of Ship's Structure


Requirements for the Preparation, Identification andManagement of Drawings


Requirements for Marker Plates


Requirements for Non�Destructive Examination Methods:

Part 1: Radiographic;

Part 2: Magnetic Particle;

Part 3: Eddy Current;

Part 4: Liquid Penetrant;

Part 5: Ultrasonic


Thermometers, Liquid in Glass Expansion Type andThermometer Pockets


Classification, Inspection Requirements and AcceptanceStandards for Castings:

Part 2: Steel Castings


Approval Systems for Welding Consumables for Structural Steels


Minimum Acceptance Standards for Welds in HM Surface Shipsand Submarines


Requirements for 70/30 Copper Nickel Alloy Material:

Part 3: Tubes


Pipework Engineering:

Part 1: General


Steel Castings for Structural, Engineering and Pressure Purposes


Fasteners:

Part 1: General


Requirements for the Classification, Dimensions, Tolerances andGeneral Standards of Acceptance for Copper and Nickel AlloyCastings

DEF STAN 05�42 Particulate Contamination Classes for Fluids in HydraulicSystems


Requirements for ac and dc Motors


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Requirements for the Preparation and Painting of Compartmentsin HM Surface Ships

DEF STAN 07�254(NES 810 Part 2)

Design Guide on the Reduction of Acoustic Noise in HM SurfaceShips:

Part 2: Reduction of Internal Airborne Noise


Requirements for Heat Exchangers (Restricted)


General Requirements for the Design of Electrotechnical andNaval Weapon Equipment

DEF STAN 08�118(NES 810 Part 1)

Design Guide on the Reduction of Acoustic Noise in HM SurfaceShips:

Part 1: Reduction of Noise Radiated Underwater


Requirements for Design and Testing of Equipments to meetEnvironmental Conditions


Selection of electronic and electrical components for use indefence equipment

DEF STAN 59�41 Electromagnetic Compatibility:

Part 2: Management and Planing Procedures;

Part 3: Technical Requirements, Test Methods and Limits;

Part 4: Large Equipment Testing;

Part 7: Code of Practice for HM Ships Installation Guidlines

DEF STAN 61�5 Electrical power supply systems below 600 volts/650 volts:

Part 1: Terminology and definitions;

Part 4: Power supplies in HM Warships

DEF STAN 66�2 Gauges Pressure Dial Indicating (Bourdon Tube Type)

BR 2000(53)(2) Hydraulic Engineering Practice

BR 3021(1) Shock Manual

BR 3021(2) Shock Manual, Volume 2 Metric

BR 3026 Ball and Roller Bearing Manual

BR 8470 Shock and Vibration Manual

BR 8471 Mounting System Design Installation and Maintenance

BR 8472 Design Report Core Cartridge Comp. Assembly in the SubmarineRefit Complex Devonport

BR 8473 Miscellaneous Mounts for Equipment Installation (to AttenuateMechanical Shock or Vibration)

DGS/PS 9023 Welding for Machinery Purposes


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ANNEX B.B.

ABBREVIATIONS AND DEFINITIONS

ANNEX B1. For the purpose of this Standard the following abbreviations and definitions apply.

ACO Automatic Change�over

ACOS Automatic Change�over Switch

AR&M Availability, Reliability and Maintainability

BIT Built in Test

BR Book of Reference

BS British Standard

BS EN British Standard European

CNSA Commodore, Naval Ship Acceptance

COS Change�over Switch

CST Contractor's Sea Trials

dB Decibel

DEF STAN Defence Standard(s) (as text dictates)

DPA Defence Procurement Agency

DTO Dockside Test Organization

EPCMS Electrical Power Control and Monitoring System

ESM Equipment Support Manager

ESP Emergency Steering Position

ETM Elapsed Time Meter

FFT Fin Feedback Transmitter

HPU Hydraulic Power Unit

HSU Hand Steering Unit

LOLER Lifting Operations and Lifting Equipment and Regulations

LP Low Pressure

MARPOL International Convention for the Prevention of Pollutionfrom Ships

MCAS Machinery Control and Surveillance

MCTA Maritime Commissioning Trials and Assessment

MDHP Motor Drive Hydraulic Pump

MOD Ministry of Defence

MTAU Machinery Trials and Assessment Unit

MTBF Mean Time Between Failures

MTTR Mean Time to Repair

NBCD Nuclear, Biological and Chemical Defence

NES Naval Engineering Standard(s)

NSR Naval Staff Requirement

OOW Officer of the Watch


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PAS Production Acceptance Specification

PCB Printed Circuit Boards

PCO Principle Contracts Officer

PM Project Manager

PSP Primary Steering Position

PTS Production Test Specification

QA Quality Assurance

RN Royal Navy

RSA Rudder Servo Amplifier

rsm Root Mean Square

SCC Ship Control Centre

SCCU Stabilizer Central Control Unit

SFLCU Stabilizer Fin Local Control Unit

SSP Secondary Steering Position

SRD System Requirement Document

STW Setting to Work

WP Working Pressure

WSA Warship Support Agency

ANNEX B2. For the purpose of this Standard the following definitions apply:

Design Authority The approved firm, establishment or branch responsible for allaspects of design of the system or sub�system which isauthorized to sign a certificate of design or certify drawings.

Prime Contractor The Prime Contractor is that company or person to whom theDPA give responsibility for total system design and forprocurement. The Prime Contractor may delegate some or allof his responsibilities but will remain liable. The PrimeContractor may be the Shipyard responsible for overall shipdesign. The Prime Contractor may employ Sub�contractors,but the Prime Contractor will retain overall responsibility forcorrectness of design.

Steering System All interconnected equipment installed in a ship exclusively toprovide controlled movement of the rudder(s) from all steeringpositions.

Steering Gear An arrangement or a combination of equipment which mayinclude actuators, pumps, electric motors, fluid systems,which together is designed to provide torque to move therudder(s).

The Hydraulic System The equipment which provides a supply of hydraulic power tothe steering actuator(s) on receipt of a signal from the controlsystem.

The Control System The equipment necessary to control the steering gear andassociated operating equipment from all steering positions.

Steering Position A compartment or area in a compartment where facilities areprovided to control ship's head through controlled ruddermovement.


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Primary Steering Position The nominated steering position for normal operation,consisting of a Hand control facility and generally an Autopilotcontrol.

Secondary SteeringPosition

The alternative steering position to be used subsequent to lossof control from the Primary Position. Mode of control to behand only.

Hand Control The steering mode in operation when a Helmsmancontinuously controls, by hand, the rudder angle and henceship's head, using the facilities provided at the Primary orSecondary Steering Position.

Emergency Steering The form of control to be effected from the Steering GearCompartment following total loss of control from the Primaryand Secondary Steering Positions, but with electrical powersupplies available.

Emergency HandOperation

A hand facility providing controlled movement of therudders(s), within the limits specified, when no electric poweris available.

Ship Control Centre A central compartment which is provided with facilities forremote control of Main and Auxiliary Machinery together withsurveillance systems for such machinery.


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ANNEX C.C.

PROCUREMENT CHECK LISTThis Standard contains no Procurement Check List information.

Notes:

1 Thi Ch k Li t i t th t t i t f thi D f St d d lt d1. This Check List is to ensure that certain aspects of this Defence Standard are consultedwhen preparing a procurement specification for a particular application.when preparing a procurement specification for a particular application.

2. Clauses where a preference for an option is to be used or where specific data are to be addedare included in the Check Listare included in the Check List.

3. Each item is to be marked either:3. Each item is to be marked either:

� = included� included

NA = not applicable

Check No. Check Clause No. � or NA

1 Is the level of requirements for drawings stated? 3.1

2 Have all environmental and operational been stated? 3.2

3 Has the steering performance been defined? 4.1.2

4 Are the modes of operation defined? 4.1.2

5 Are the methods of control stated? 4.1.2

6 Is the siting of the control function required stated? 4.1.2

7 Has the maximum period of operation been stated? 4.1.2

8 Are the availability and reliability targets stated? 4.1.2

9 Are the frequency and duration of maintenance periods andrefits stated?

4.1.2

10 Have the over�riding features of the general designobjective been highlighted?

4.1.7

11 Has the designed length of life been stated? 4.1.9

12 Have the MTBF targets been stated? 4.1.9

13 Have the requirements for technical and maintenancepublications been stated?

4.1.11

14 Have the available power supplies been listed? 3.3.1

15 Have the data transmission requirements been stated? 4.1.5

16 Is the type of data transmission stated? 4.1.5

17 Are the positions where Autopilots are to be fitted stated? 4.3.2

18 Is the provision of all external test points on the Autopilotstated?

4.3.9

19 Is the hardover to hardover time stated? 1.1.3

20 Do the motor starters require additional remote

START/STOP facilities?

3.3.2

21 Are hull glands required to be maintained afloat? 3.4.6

22 Have the details of instrumentation requirements been

stated?

3.4.3


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Check No. Check Clause No. � or NA

23 Are the nature of cabling and terminations of ship supplies

and signal lines identified?

3.4.5

24 Have the pressure test requirements been established

where applicable?

3.11.3

DEF STAN 02–339 / ISSUE 2 (NES 339 )

59

ALPHABETICAL INDEX

AActuators, 45

Availability, 10, 11

BBearings, 17

CCocks, 46

Controls, 36

Operator Controls, 36

Operator Displays, 36

DData Transmission, 27

Design Parameters, 25, 27, 28, 29, 30, 31, 32

Availability, 28

Design Objectives, 28

Ease of Operation, 31

Economy of Space, 31

Emergency Hand Operation, 31

Fundamental Requirements, 25

Lubrication System, 32

Maintainability, 29

Materials and Weight, 30

Reliability, 29

Ship Characteristics, 27

Software, 32

Vulnerability, 30

EElectric Motors, 10

Standard Range, 10

Electrical Components, 16

Printed Circuit Boards, 16

Electrical Connections, 16

Cable Entries and Terminations, 16

Electronic components, 42

FFault diagnosis, 42

Filtration, 46

Flushing, 46

Fin angle limitation, 42

GGlands, 16

Guage Board, 16

HHeat Exchangers, 45

Hydraulic System, 44, 45, 46

Contamination, 46

Fluid Reservoir, 45

Hand Pump, 46

Pumps, 44

Relief Valve, 46

IInstallation, 20

Instrumentation, 15

LLubrication System, 18

Bearings/Stocks, 18

MMarker Plates, 18

Materials, 18

Castings, 18

DEF STAN 02–339 / ISSUE 2 (NES 339 )

60

Welding, 18

NNavigation System, 34

Noise shorts, 17

PPackings, 16

Pipework, 46

Preservation and Maintenance, 18, 19

Flexible Hoses, 19

General, 18

Maintenance in Stores, 18

Maintenance On-board, 18

Pressure gauge, 20

Pressure Testing, 20

Pressure testing, 20

Printed circuit boards, 42

Pump Drive Coupling, 47

QQuiet running, 42

RRudder Angle Indication, 10, 33

Rudder Hydraulic System, 9

Rudder Servo System, 34, 39, 41

Rudder Control, 39

Rudder Feedback Transmitter, 34

Rudder Servo Amplifier, 41

SSafety, 18

Lifting, 18

Protective Guard, 18

Screw Threads, 15

Seals, 16

Setting to Work, 21

Shop pressure test, 20

Socket connector, 42

TTest meter, 42

Test Requirements, 19

Testing after manufacture, 20

Trials, 21, 22, 23, 24

Basin Trials, 23

Contractors Sea Tials, 24

Final Machinery Demonstration, 24

General, 21

Preliminary Basin Trials, 22

UUpkeep, Maintainability and

Interchangeability, 28, 30

Equipment Interchangeability, 30

Interchangeability, 30

Upkeep Policy, 28

VValves and Cocks, 17

ZZero Fin condition, 42

Inside Rear Cover

© Crown Copyright 2002

Copying Only as Agreed with DStan

Defence Standards are Published by and Obtainable from:

Defence Procurement AgencyAn Executive Agency of The Ministry of Defence

Directorate of StandardizationKentigern House65 Brown Street

GLASGOW G2 8EX

DStan Helpdesk

Tel 0141 224 2531/2 Fax 0141 224 2503

Internet e-mail [email protected]

File Reference

The DStan file reference relating to work on this standard is D/DStan/69/02/339.

Contract Requirements

When Defence Standards are incorporated into contracts users are responsible for their correctapplication and for complying with contractual and statutory requirements. Compliance witha Defence Standard does not in itself confer immunity from legal obligations.

Revision of Defence Standards

Defence Standards are revised as necessary by up issue or amendment. It is important thatusers of Defence Standards should ascertain that they are in possession of the latest issue oramendment. Information on all Defence Standards is contained in Def Stan 00-00 Standardsfor Defence Part 3 , Index of Standards for Defence Procurement Section 4 ‘Index of DefenceStandards and Defence Specifications’ published annually and supplemented regularly byStandards in Defence News (SID News). Any person who, when making use of a DefenceStandard encounters an inaccuracy or ambiguity is requested to notify the Directorate ofStandardization (DStan) without delay in order that the matter may be investigated andappropriate action taken.

NES 339 Requirements for Steering and Stabilizer Systems for HM Surface Ships and Royal Fleet...

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Transcript of NES 339 Requirements for Steering and Stabilizer Systems for HM Surface Ships and Royal Fleet...