What characterizes an aircraft accident?

The correct characterization of an aircraft accident is defined as an occurrence involving an aircraft from the moment a person boards with the intention of flight until all persons have disembarked, resulting in serious injury, death, or significant damage to the aircraft. This definition is broad enough to cover a wide range of serious incidents that occur during the entire flight process, emphasizing the severity of the injuries or damage involved.

The focus on the period between boarding and disembarking is crucial, as it designates the entire flight operation as a context within which accidents are assessed. Serious injury or significant damage indicates that not only should the event involve the aircraft in a capacity related to flight, but it must also have adverse outcomes, reflecting the purpose of investigating such events under regulations like those from the National Transportation Safety Board (NTSB) and the aviation industry at large.