In-flight Fire
Fire or smoke aboard in flight. It is time-critical: historically, crews have had well under half an hour from the first smell of smoke.
In-flight fire investigations focus on the ignition source (wiring, cargo, lithium batteries, oxygen generators), the material that let the fire propagate, and the detection and suppression available in that compartment.
The other half is the crew response: smoke drills, whether the aircraft was landed immediately, and whether the checklist sequence cost time the fire did not allow.
Related terms
A formal proposal from the investigators to a regulator or operator. Recommendations are not binding: the regulator decides what to mandate.
A component or system failed in service. The investigation asks why the part failed and why the failure was not contained by design, inspection or redundancy.