Processes and Programmes Leading from Certification to Operation

1. Processes and Programmes Leading from Certification to Operation The Route to Continuing Airworthiness Brian L Perry BSc (Eng), C.Eng, FRAeS, MIET Vice President (Technical), International Federation of AirworthinessAirworthiness Consultant

2. Content • A bit of History • An overview of where we are Now • A brief look into the Future

3. Where It All Began

4. 1930’s Airliner

5. Douglas DC3 G-AMRA - Norwich UK - May 2008 Andrew McClymont

6. AIRWORTHINESS • “Airworthiness” organisations had been set up, before the war, both in the UK (1934) and the USA (1938). • Aircraft development during the war was driven by military needs. • By 1944 the rapid growth of Civil Aviation led to the establishment of an International organisation.

7. Airworthiness • What is meant by the term Airworthiness My Definition:

8. Airworthiness and Continuing Airworthiness FITNESS TO FLY SAFELY THROUGH OUT THE LIFE OF THE AIRCRAFT Dependent upon: • Design and Manufacture • Operations • Maintenance and Repair

10. International Civil AviationOrganisation • Under The 1944 Chicago Convention the various National Governments agreed to set up an International Organisation, ICAO, in order that: • “----International civil aviation may be developed in a safe and orderly manner---” • “---and to secure the highest practicable degree of uniformity in regulations, standards and procedures---”

11. ICAO Annexes • 18 Annexes including: • Personnel Licensing and Approval of Organisations • Rules of the air • Meteorological Services • Aeronautical Charts • Units of Measurement • Operation of aircraft • Aircraft registration Marks • Airworthiness and Continuing Airworthiness

12. Annexes continued • Facilitation • Aeronautical Telecommunication • Air Traffic Services • Search and Rescue • Aircraft Accident Investigation • Aerodromes • Aeronautical Information Services • Environmental Protection • Security • Transport of Dangerous Goods by Air

13. ICAO SARPS Standards And Recommended Practices for the interpretation of the Annex material

14. Implementation of Annexes and SARPS • In practice these are implemented by National Codes such as: • In the Europe by JARs now EASA CS’s. • In the USA by FAR’s. • In most other counties by National Codes often based upon or related to FAR’s and/or the EASA Codes.

15. FAA---------------------------------------------EASA FAR’s - Requirements - CS’s Acceptable Means of Compliance - AMC’s Appendices AC’s - Advisory Circulars _________________________________________________________ SAE/RTCA ------------------------------- EUROCAE ARINC ARINC Detailed Specifications and Guidance material eg. DO 160/ED 14, DO 178/ED12 etc. ________________________________________ Prime Manufactures in-house standards which are applicable to all sub contractors and suppliers

17. High Accident Rates particularly related to piston engine failures

18. A Major Step for SafetyIntroduction of Jet Engines • Cabin Air Conditioning and Pressurisation • Increased cruise altitude speed and range • Increase in engine reliabilityBUT in some early jet-engined aeroplanes: • Accidents caused by Structural Fatigue • Results of the investigations and tests and the resultant changes to the airworthiness requirements were shared across the world.

19. De Havilland Comet

20. Another Major Step

21. Concorde - Advanced Systems • High Speed and High Altitude • Limited Fly- by Wire • Extreme Temperatures on Aircraft skin • Reheat and Full Authority Electronic Engine Controls • Full Authority, Safety Critical, Digital Air Intake controls • Centre of Gravity Control using Aircraft Fuel • Equipment Cooling using Aircraft Fuel • Exposure to Radiation and Lightning Strikes

22. Lightning Strike

23. Current Requirements • The Concorde and other experience led to major changes in the requirements, in particular for the certification of Systems and Equipment which are applicable throughout the in-service life of the aeroplane • These will be discussed in more detail later in this presentation.

24. Airworthiness • We shall today be concentrating upon Part 25 Requirements covering the TC (Type Certification) of Large Aeroplanes. • These requirements also take account of all the ICAO annexes and their related national standards. • Plus Systems and Equipment fitted to obtain a C of A (Certificate of Airworthiness)

25. Certification Specifications forAirworthiness of Large Aeroplanes CS 25 • Subpart A - Applicability • This airworthiness Code is applicable to Turbine Powered Large Aeroplanes over 5670kg weight • Operated under Part 121(or similar rules)

26. CS 25 SubpartsAlso containing Appendices andAMC’s • B – Flight • C – Structure • D – Design and Construction • E – Powerplant • F – Equipment • G – Operating Limits and Information • J – Gas turbine APU Installations

27. Some Sections of CS 25 which are particularly related to Continuing Airworthiness • Weight and Centre of Gravity limits. • Guidance for in-service flight tests, where required following maintenance actions. • AMC 25.561 – Load conditions for seats and other items of ‘commercial’ equipment. • AMC 25.581-- Lightning protection and bonding of structural elements. • Provision of CDL (Configuration Deviation List) information for Flight Manual.

28. Some Sections of CS 25 which are particularly related to ContinuingAirworthiness (ctd.) • Much of the content of Subpart D – Design and Construction including, for example: • AMC’s No. 1 and 2 to CS.603. Suitability of materials including Appendix F - Fire Test Criteria and Procedures. • Emergency Exits arrangements and Emergency Demonstration - Appendix J. • Appendix H – Instructions for Continuing Airworthiness which details, in particular, the required content of the Maintenance Manuals.

29. Some Sections of CS 25 which are particularly related to Continuing Airworthiness (ctd.) • Requirement for Engine Type Certification. • Design Considerations for Minimizing Hazards caused by Uncontained Turbine Engine and APU Rotor Failure, AMC 20-128A. • Detailed information on the contents of the Flight Manual including CDL and MMEL, AMC 25.1581. • Requirement for APU approval.

30. SEE ALSO IFA WHITE PAPER Dated April 2003 CONTINUING AIRWORTHINESS The basic story

31. CS 25 Subpart F - Equipment • The Concorde and other experience led to major changes in the requirements, in particular for the certification of Systems and Equipment which are applicable throughout the in-service life of the aeroplane • For example the concept of the inverse relationship between the probability of occurrence of an event and the severity of its effect. • These and the related certification procedures are as detailed in 25.1309 and the associated AMC’s or AC’s.

34. FAA---------------------------------------------EASA FAR’s - Requirements - CS’s Acceptable Means of Compliance - AMC’s Appendices AC’s - Advisory Circulars _________________________________________________________ SAE/RTCA ------------------------------- EUROCAE ARINC ARINC Detailed Specifications and Guidance material eg. DO 160/ED 14, DO 178/ED12 etc. ________________________________________ Prime Manufactures in-house standards which are applicable to all sub contractors and suppliers

35. Extract from CS 25.1309 (a)(1) • Systems and equipment must be designed and installed so that those required for Type Certification or by operating rules, or whose improper functioning would reduce safety, must perform as intended under the aeroplane operating and environmental conditions

36. Extract from CS 1309 (a)(2) • The aeroplanes systems and equipment must be designed so that other equipment and systems are not a source of danger in themselves and do not adversely affect the proper functioning of those covered by CS 25,1309 (a)(1) • SEE ALSO AMC 25.1309

37. Systems and Equipment Certification Requirements • While subpart F of the requirements and, in particular, 25.1309, covers the certification of Systems and Equipment, their specific requirements may be detailed in other sub parts. • For example the subparts and associated Appendices and AMC’s, covering: • Flight, Structures, Design and Construction, Power Plant, Operating Limits, Auxiliary Power Units (APU’s). • Including any new equipment and systems required or fitted after entry into service.

38. The Type Certification Process • A review of this process will now be made. • The steps shown contain information which may need to be taken into account when any in-service modifications, repairs or replacements are made to the aircraft, its systems and its equipment.

40. Preliminary Hazard Analysis –PHAFailure Conditions and Criticalities • Determines system hazards and effects –Catastrophic, Hazardous, Major, Minor, No Safety Effects and the associated level of analysis required . • Hence Safety Objectives • Quantitative or Qualitative analysis • Involves system designers and pilots • Agreed between Design Organisation and Certification Authorities

41. Software Verification and Validation • Document used Internationally for V & V RTCA - DO 178B (Eurocae – ED 12B) • Amount of work depends upon Software Levels • Watch out for the need for ‘Partitioning’ which separates those portions which can be modified after Type Certification and those which cannot. • Summarised in Accomplishment Summary

42. Software Levels

43. Equipment Approval • All equipment fitted to the aircraft must be tested to ensure that it meets all the relevant environmental and safety standards, as specified in DO 16O, or the airframe manufacturers equivalent specification. • Evidence must be provided to confirm this, for example: TSO (Technical Standing Order) or DDP (Declaration of Design and Performance. • Information on failure modes and reliability rates will, where relevant, be required for use in the FMEA.

44. FMEA - Failure Modes and Effects Analysis • This will be required for those systems where a quantitative analysis of the particular event is required by the PHA. • Normally carried out by the airframe constructor using a computer programme. • All sub systems and equipment failure and reliability information used in the analyses to be to the same standard.

45. Rig and Aircraft Tests • These are particularly relevant in the evaluation of complex system inter-reactions and related system indications, warnings and procedures, under normal, standby and emergency conditions. For example: power supply failures and bus-bar failures. • Establish Flight Manual procedures. • Involvement of the flight test crew is essential. • In-service changes and additions must not affect these, otherwise a formal amendment is needed.

46. Zonal Analysis • Initial confirmation that the design standards cover the requisite Zonal Configurations. • Including: fire and explosion; corrosion; segregation and separation of power supplies and back-up systems and associated earthing/grounding; disc burst zones; other electrical and mechanical segregation requirements; physical fastening and protection of cables and equipment; safe and easy access for required maintenance activities. • These standards remain critical throughout the service life of the aircraft and must not be invalidated

47. Zonal Analysis (continued) • Detailed inspection of the completed aircraft to ensure that these standards are met and to ensure that no other potential safety hazards have been introduced during manufacture. • This can be a difficult and potentially time consuming task, but it is essential to ensure that these standards are maintained throughout the in-service life of the aeroplane.

48. System Safety Assessment - SSA • This process confirms that: • The assumptions of the PHA are correct, or have to be modified, and that the derived System Safety Objectives have been met. • That the installation of the equipment on the aircraft meets the design standards and no further potential hazards have been introduced. • Provides Flight Manual Procedures covering the relevant system and equipment failure conditions. • Provides MMEL (Master Minimum Equipment List) information and any related operational or time restraints, based upon the data used in the assessments.

49. SSA (continued) • Details any CMR (Certification Maintenance Requirements) which have shown to be essential to retaining the required levels of reliability and availability, during the SSA and FMEA process, and which cannot be changed using normal in-service procedures, AMC 25-19 • Provides other information as required by the pre-operations maintenance review panel (MSG-3). • Provides the basis for the Compliance Check List for 25.1309.

50. In Service Experience • The Airbus range of Fly By Wire aircraft • (A319, A320, A330, A340) were the first civil aircraft designed and certificated to these standards using these or equivalent certification processes. • Also the FBW Boeing 777, with this aircraft also utilising a ‘Digital Data Bus’ System.