Accident and Incident Investigation: Definitions and Obligations
Definitions that drive the answer
The distinction between an accident and an incident is the single most tested point. An accident involves an occurrence associated with the operation of an aircraft in which a person is fatally or seriously injured, the aircraft sustains damage or structural failure, or the aircraft is missing or inaccessible. An incident is an occurrence, other than an accident, associated with the operation that affects or could affect safety. Traps present a serious occurrence with no injury or damage and expect the candidate to call it an accident - it is an incident, possibly a serious incident.
Notification
Know who must notify whom and how quickly. The operator must notify the State of occurrence, the State of registry, the State of the operator, the State of design and the State of manufacture as applicable. The purpose of notification is to enable investigation, not to assign blame.
Investigation principles
Investigations are independent and safety-focused. The sole objective is prevention of future accidents, not apportionment of blame or liability. Know the roles: the State of Occurrence normally conducts the investigation and may delegate; other States may appoint accredited representatives. Traps include assuming a criminal investigation replaces a safety investigation, or that the safety report may be used to establish liability.
Reports and records
Know the distinction between the preliminary report, the factual report and the final report, and the requirement to preserve evidence including recorders. Also know the protection of safety data - the investigation's records are generally not for public disclosure.
Worked example
An aircraft suffers a serious engine fire in flight but lands safely with no injury and only the engine damaged. Because the damage is not to the aircraft structure and no one is seriously injured, this is normally a serious incident, not an accident. Rule of thumb: injury, structural damage or missing aircraft - otherwise it is an incident.