Accident and Investigation

Accident and Investigation: Key ATPL Concepts and Procedures

In international aviation, accident and incident investigation is governed by ICAO Annex 13 and reflected in national aviation regulations. A central principle for ATPL students to know is that the Authority of the State in which the occurrence takes place (State of Occurrence) is responsible for instituting and conducting the investigation, though it may delegate this task. Other States—such as the State of Registry, State of the Operator, State of Design, and State of Manufacture—may appoint accredited representatives and are entitled to participate. The sole objective of any safety investigation is the prevention of future accidents and incidents; it is not to apportion blame or liability.

Understanding classification is essential for exam success and operational decision-making. An accident typically involves: (1) a person suffering fatal or serious injury associated with the operation of the aircraft (including during embarkation/disembarkation or contact with the aircraft, such as a passenger striking the wing’s trailing edge on the apron), (2) the aircraft sustaining damage or structural failure that adversely affects structural strength, performance, or flight characteristics and would normally require major repair or replacement (for example, landing gear sinking into a hole during taxi causing structural damage), or (3) an aircraft being missing or completely inaccessible. A serious incident is an occurrence where circumstances indicate a high probability of an accident if conditions had been slightly different—such as pilot incapacitation during climb-out resulting in a precautionary return to land. Recognizing these thresholds ensures the correct procedures, notifications, and reports are initiated without delay.

Flight crew and operators have clear procedural obligations after an occurrence. Immediate priorities are safety and medical assistance, followed by notifying ATS and the operator per SOPs. Crews must preserve evidence: protect the site and wreckage (if applicable), retain documentation, and safeguard flight recorders (FDR/CVR)—do not erase or power-cycle the CVR unless permitted by the Authority. The operator’s Safety Management System (SMS) details internal and external occurrence reporting (e.g., Air Safety Reports or Mandatory Occurrence Reports) to the appropriate Authority “as soon as practicable” and within any State-specified timelines. Technical staff may assist with securing recorded data, maintenance logs, and relevant aircraft systems information for investigators. Throughout, the guiding intent remains prevention, with safety recommendations and final reports disseminated to improve procedures, training, and system design.

What this question bank covers

• Roles and responsibilities under ICAO Annex 13 (State of Occurrence, Registry, Operator, Design, Manufacture)
• Definitions and classification: accident vs serious incident, including typical ATPL exam scenarios
• Crew and operator procedures: immediate actions, ATS notification, SMS/MOR/ASR reporting
• Evidence preservation and handling of FDR/CVR and operational data
• Examples: apron injuries, crew incapacitation, structural damage during taxi
• Investigation objectives, safety recommendations, and prevention-focused outcomes