An aviation accident is defined in the
International Civil Aviation Organisation Annex 13. The definition may be summarised as: An occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of
flight and all such persons have disembarked, in which:a) a person is fatally or seriously injured b) the aircraft sustains damage or structural failure; orc) the aircraft is missing or is completely inaccessible.
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An occurrence, other than an accident, associated with the operation of an aircraft that affects or could affect the safety of operations and that is investigated and reported on FAA Form 8020-5.
(FAA3)