Lost in Translation: Misrigged Main Landing Gear
The French BEA-D (Le Bureau Enquêtes Accidents Défense – Air) 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:
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