Accident and Incident Investigation
Annex 13 and the investigation objective
Annex 13 governs aircraft accident and incident investigation. Its stated objective is prevention, not the apportionment of blame or liability. The State of Occurrence is normally responsible for instituting the investigation, though it may delegate to another State. The State of Registry, State of the Operator, State of Design, and State of Manufacture may be entitled to participate as accredited representatives.
Definitions
An accident involves a person boarding or on board an aircraft with the intention of flight, in which a person is fatally or seriously injured, the aircraft sustains substantial damage, or the aircraft is missing or inaccessible. An incident is an occurrence, other than an accident, that affects or could affect the safety of operations. A serious incident is one likely to result in an accident. These definitions are a favourite testing ground.
The investigation process
The investigator-in-charge leads, with a team of experts. The final report is published, and States may comment. Safety recommendations are addressed to States and operators, not to courts. Privileged information (CVR and FDR recordings) is protected and not released for disciplinary or judicial purposes except under specified conditions.
Traps
Questions often claim the purpose is to determine blame, that the State of Registry always leads, or that the CVR may be freely disclosed. Another trap confuses an incident with a serious incident.
Rule of thumb
Ask: was anyone fatally or seriously injured, was there substantial damage, or is the aircraft missing? If yes, it is an accident. If not, it is an incident or serious incident.