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An accident is defined as:
An occurrence associated with the operation of an aircraft which, in the case of a manned aircraft, takes place between the time any person boards the aircraft with the intention of flight until such time as all such persons have disembarked, or in the case of an unmanned aircraft, takes place between the time the aircraft is ready to move with the purpose of flight until such time as it comes to rest at the end of the flight and the primary propulsion system is shut down, in which:
a) a person is fatally or seriously injured as a result of:
- being in the aircraft, or
- direct contact with any part of the aircraft, including parts which have become detached from the aircraft, or
- direct exposure to jet blast,
except when the injuries are from natural causes, self-inflicted or inflicted by other persons, or when the injuries are to stowaways hiding outside the areas normally available to the passengers and crew; or
b) the aircraft sustains damage or structural failure which:
- adversely affects the structural strength, performance or flight characteristics of the aircraft, and
- would normally require major repair or replacement of the affected component,
except for engine failure or damage, when the damage is limited to the engine, its cowlings or accessories; or for damage limited to propellers, wing tips, antennas, tires, brakes, fairings, small dents or puncture holes in the aircraft skin; or
c) the aircraft is missing or is completely inaccessible.
Note 1.— For statistical uniformity only, an injury resulting in death within thirty days of the date of the accident is classified as a fatal injury by ICAO.
Note 2.— An aircraft is considered to be missing when the official search has been terminated and the wreckage has not been located.
Note 3.— In the case of investigation of an unmanned aircraft system, only aircraft with a design and/or operational approved are to be considered.
Note 4.— Guidance for the determination o f aircraft damage can be found in Attachment E to ICAO Annex 13.
(ICAO Annex 13 (Aircraft Accident and Incident Investigation))
ICAO Annex 13 (Aircraft Accident and Incident Investigation). ICAO Accident/Incident Reporting Manual (Doc 9156).