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Aircraft Certification and Production Standards
Aircraft Certification Requirements
Aircraft certifications requirements are derived from ICAO Annex 8 ‘Airworthiness of Aircraft’ and ICAO Doc. 9760 “Airworthiness Manual” Volume II ‘Design Certification and Continuing Airworthiness”. Each contracting state then establishes its own applicable regulations to implement internationally agreed standards and recommended practices.
Comparison of US and EU Regulations
In the USA and EU, procedures for certification of aeronautical products and the related organisational approvals are published in FAR Part 21 and EC Regulation 748/2012 respectively. In addition to these procedures, the requirements/specifications for certification of each category of products are published in different regulations and certification specifications.
The fundamental difference between the USA and EU system in this regard is that Certification Specifications published by EASA are non-binding technical standards. However, compliance with CS is a necessary condition for obtaining the relevant regulatory approval or certification. CS material may therefore be regarded as binding when taken in conjunction with the binding rules which require compliance with the CS. EASA Certification Memoranda provide another perspective on this matter.
The following list shows a list of airworthiness standards (US) and certifications specifications (EU) applicable to different categories of aircraft.
|Electronic Code of Federal Regulations||EASA Certification Specification|
|FAR Part||Title||EASA CS||Title|
|CS-22||Sailplanes and Powered Sailplanes|
|23||AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES||CS-23||Normal, Utility, Aerobatic and Commuter Aeroplanes|
|25||AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES||CS-25||Large Aeroplanes|
|27||AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT||CS-27||Small Rotorcraft|
|29||AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT||CS-29||Large Rotorcraft|
|31||AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS||CS-31GB CS-31HB||(Gas Balloons) (Hot Air Balloons)|
|33||AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES||CS-E||Engines|
|35||AIRWORTHINESS STANDARDS: PROPELLERS||CS-P||Propellers|
|CS-LSA||Light Sport Aeroplanes|
|CS-VLA||Very Light Aeroplanes|
|CS-VLR||Very Light Rotorcraft|
Acceptable Level of Safety
As part of the type certifications process, particularly for transport category aeroplanes, manufacturers need to demonstrate how they meet the acceptable level of safety defined in Part 25 and CS 25. Such specifications also makes reference to ARP4761 "Guidelines & Methods for Conducting Safety Assessment Process on Civil Airborne Systems and Equipment", which details the methodologies to be used such as:
- Functional Hazard Assessment,
- Fault Tree Analysis,
- Failures Modes and Effects Analysis,
- Common Cause Analysis,
- Zonal Safety Analysis,
- Particular Risk Analysis and
- Common Mode Analysis.
Unfortunately there are number of accidents that could have been prevented by more effective use of these methodologies.
Quality Management System
In addition to the robust design processes and compliance with the regulations to demonstrate acceptable level of safety, the TC holder must have effective quality management systems in place, particularly in order to ensure that the parts received from supply chain meets the required standards. For this reason International Aerospace Quality Group has created the AS/EN 9100 family ‘Quality Management System Standards for Aerospace Industry’. Since their introduction in 1999, they have been continually developed and revised and, currently, specific standards are published for manufacturing organisations (AS/EN9101), maintenance organisations (AS/EN 9111), part suppliers (AS/EN9121) etc.
Accidents and Incidents
The following events for which reports held on SKYbrary cite an OEM design fault as a contributory factor:
- E145, New York JFK USA, 2007 (On 17 December 2007, an Embraer 145 being operated by Chautauqua Airlines on a Delta Connection passenger flight departing New York JFK runway 31L for an unrecorded destination carried out a high speed rejected take off in normal day visibility when the response to elevator control input at rotation was abnormal.)
- B732, Pekanbaru Indonesia, 2002 (On 14 January 2002, a Boeing 737-200, operated by Lion Air, attempted to complete a daylight take off from Pekanbaru, Indonesia without flaps set after a failure to complete the before take off checks. The rejected take off was not initiated promptly and the aircraft overran the runway. The take off configuration warning failed to sound because the associated circuit breaker was so worn that it had previously auto-tripped and this had not been noticed.)
- AT76, vicinity Taipei Songshan Taiwan, 2015 (On 4 February 2015, a TransAsia Airways ATR 72-600 crashed into the Keelung River in central Taipei shortly after taking off from nearby Songshan Airport after the crew mishandled a fault on one engine by shutting down the other in error. They did not realise this until recovery from loss of control due to a stall was no longer possible. The Investigation found that the initial engine fault occurred before getting airborne and should have led to a low-speed rejected take-off. Failure to follow SOPs and deficiencies in those procedures were identified as causal.)
- E145, Kemi-Tornio Finland 2008 (On 11 December 2008 an EMB 145 being operated by Finnish Commuter Airlines on a scheduled passenger flight caught fire during the taxi in after a night landing after the APU failed to start and a major electrical power failure occurred simultaneously. The fire was not detected until after the aircraft arrived on stand when, with the passengers still on board, a member of the ground crew saw signs of fire at the back of the aircraft. The aircraft’s own fire suppression system was successfully used to extinguish the fire, the passengers left the aircraft and there were no injuries and only minor damage to the aircraft.)
- F27, vicinity Jersey Channel Islands, 2001 (Shortly after take-off from Jersey Airport, Channel Islands, a F27 experienced an uncontained engine failure and a major fire external to the engine nacelle. The fire was extinguished and the aircraft landed uneventfully back at Jersey.)
- B762, Los Angeles USA, 2006 (On June 2, 2006, an American Airlines Boeing 767-200ER fitted GE CF6-80A engines experienced an uncontained failure of the high pressure turbine (HPT) stage 1 disc in the No. 1 engine during a high-power ground run carried out in designated run up area at Los Angeles for maintenance purposes during daylight normal visibility conditions. The three maintenance personnel on board the aircraft as well as two observers on the ground were not injured but both engines and the aircraft sustained substantial damage from the fuel-fed fire which occurred as an indirect result of the failure.)
- F50, vicinity Luxembourg, 2002 (On 6 November 2002, a Fokker 50 operated by Luxair, crashed on approach to Luxembourg Airport following loss of control attributed to intentional operation of power levers in the ground range, contrary to SOPs.)
- A320, São Paulo Congonhas Brazil, 2007 (On 17 July 2007, the commander of a TAM Airlines Airbus A320 being operated with one thrust reverser locked out was unable to stop the aircraft leaving the landing runway at Congonhas at speed and it hit buildings and was destroyed by the impact and fire which followed killing all on board and others on the ground. The investigation attributed the accident to pilot failure to realise that the thrust lever of the engine with the locked out reverser was above idle, which by design then prevented both the deployment of ground spoilers and the activation of the pre-selected autobrake.)
- A332, en-route, Atlantic Ocean, 2009 (On 1 June 2009, an Airbus A330-200 being operated by Air France on a scheduled passenger flight from Rio de Janeiro to Paris CDG as AF447 exited controlled flight and crashed into the sea with the loss of the aircraft and all 228 occupants. It was found that the loss of control followed an inappropriate response by the flight crew to a transient loss of airspeed indications in the cruise which resulted from the vulnerability of the pitot heads to ice crystal icing.)
- MD82, Madrid Barajas Spain, 2008 (On 20 August 2008, an MD82 aircraft operated by Spanair took off from Madrid Barajas Airport with flaps and slats retracted; the incorrect configuration resulted in loss of control, collision with the ground, and the destruction of the aircraft.)
- B738, en-route, near Lugano Switzerland, 2012 (On 4 April 2012, the cabin pressurisation controller (CPC) on a Boeing 737-800 failed during the climb passing FL305 and automatic transfer to the alternate CPC was followed by a loss of cabin pressure control and rapid depressurisation because it had been inadvertently installed with the shipping plug fitted. An emergency descent and diversion followed. The subsequent Investigation attributed the failure to remove the shipping plug to procedural human error and the poor visibility of the installed plug. It was also found that "the pressurisation system ground test after CPC installation was not suitable to detect the error".)
- B772, en-route Bozeman MT USA, 2008 (On 26 November 2008, a Boeing 777-200 powered by RR RB211 Trent 800 series engines and being operated by Delta AL on a scheduled passenger flight from Shanghai Pudong to Atlanta was in the cruise at FL390 in day VMC in the vicinity of Bozeman MT when there was an uncommanded thrust reduction or ‘rollback’ of the right engine.)
- … further results