Lost in Translation: Misrigged Main Landing Gear
The French BEA-D (Le Bureau Enquêtes Accidents Défense – Air (UPDATE: renamed the BEA d’État [BEA-É] in 2018 in recognition of its role in all state aircraft) has issued the final report into their investigation of a landing gear collapse on Canadair CL-415 F-ZBEU of the Securité Civile at Ajaccio-Napoleon Bonaparte Airport, Corsica on 1 August 2016.
The fire bomber, callsign ‘Pélican 42’, was one of two aircraft taxying for take-off when the right hand Main Landing Gear (MLG) collapsed as the aircraft turned to align with runway 20 for take off.
In particular the right hand float was damaged, and a fuel leak occurred.
The MLG is locked by a strut by the principle of a geometric locking by overextension. When examined the MLG strut was found to be outside the allowable range which led to premature wear of the components of the strut assembly.
The recommended value for X in the Component Maintenance Manual (CMM):
Dimension X must be equal to dimension Y or up to a maximum of 0.055 inch (1.40 mm) less than dimension Y.
The investigation revealed that the maintenance organisation overhauling the landing gear struts had translated the CMM from English to French but had made an error with this dimension:
The landing gear was jolted unlocked when the aircraft taxied onto the runway at a higher than intended speed (c 14 knots rather than 6 knots).
Aerossurance has previously published:
- Maintenance Human Factors in Finnish F406 Landing Gear Collapse
- Aircraft Maintenance: Going for Gold?
- Professor James Reason’s 12 Principles of Error Management
- Critical Maintenance Tasks: EASA Part-M & -145 Change
- Airworthiness Matters: Next Generation Maintenance Human Factors
- B747 Landing Gear Failure Due to Omission of Rig Pin During Maintenance
- When Down Is Up: 747 Actuator Installation Incident
- Maintenance Human Factors in Finnish F406 Landing Gear Collapse Safety investigators discuss the associated maintenance human factors and inadequacies in the type’s maintenance instructions.
- UPDATE 24 June 2018: B1900D Emergency Landing: Maintenance Standards & Practices The TSB report posses many questions on the management and oversight of aircraft maintenance, competency and maintenance standards & practices. We look at opportunities for forward thinking MROs to improve their maintenance standards and practices.
- UPDATE 25 August 2018: Crossed Cables: Colgan Air B1900D N240CJ Maintenance Error On 26 August 2003 a B1900D crashed on take off after errors during flying control maintenance. We look at the maintenance human factor safety lessons from this and another B1900 accident that year.
- UPDATE 3 November 2018: A Lufthansa MD-11F Nose Wheel Detached after Maintenance Error
- UPDATE 28 April 2020: Beech 99A MLG Collapse
- UPDATE 3 June 2020: Beechcraft 1900C Landing Gear Collapse at San Antonio, TX
- UPDATE 16 June 2020: CRJ-200 Landing Incident Highlighted US Maintenance Competency Inadequacies
- UPDATE 23 June 2020: Myanmar National Embraer 190 NLG Jam: Maintenance Error? We’re Not Convinced!
- UPDATE 12 October 2020: Frozen Dash 8-100 Landing Gear After ‘Improper Maintenance Practices’ Say NTSB
Aerossurance is pleased to sponsor the 9th European Society of Air Safety Investigators (ESASI) Regional Seminar in Riga, Latvia 23 and 24 May 2018.
Aerossurance is pleased to be both sponsoring and presenting at a Royal Aeronautical Society (RAeS) Human Factors Group: Engineering seminar Maintenance Error: Are we learning? to be held on 9 May 2019 at Cranfield University.