Human Factors (Maintenance)
An engineering or maintenance action (a part fitted wrongly, an inspection missed, a repair done off-manual) contributed to the accident.
Maintenance-caused accidents rarely trace to a single careless engineer. They surface shift handovers, documentation that did not match the aircraft, tooling and access constraints, night work, and repairs signed off against the wrong procedure.
Because the defect is often introduced weeks or years before the flight, these investigations lean heavily on maintenance records, work cards and airframe history, which is why case files here carry airframe hours, cycles and the last major check where they are known.
Related terms
How much life the airframe has used. Hours measure time in service; a cycle is one takeoff and landing, and it is cycles that drive fatigue.
The airframe itself broke, usually through fatigue cracking, corrosion, an improper repair, or loads beyond what the structure could take.
Decisions and pressures outside the flight deck (dispatch, loading, scheduling, air traffic services, company culture) that shaped the outcome.