For occurrences not classified as an Accident (as per ICAO Annex 13 definition), we use these criteria for inclusion in the ASN Database:

(Serious) incidents:

• Runway incursions classified with severity A or B. (See ICAO Doc 9870; 6.1.3)
• Near collisions/Airprox incidents classified with severity A or B.
• Collisions not classified as accidents.
• Controlled flight into terrain only marginally avoided.
• Take-offs from a closed or engaged runway, from a taxiway or unassigned runway.
• Landings or attempted landings on a closed or engaged runway, on a taxiway, on an unassigned runway or on unintended landing locations such as roadways.
• Retraction of a landing gear leg or a wheels-up landing not classified as an accident.
• Dragging during landing or takeoff of a wing tip, an engine pod, propeller, tail or any other part of the aircraft.
• Gross failures to achieve predicted performance during take-off or initial climb.
• Fires and/or smoke in the cockpit, in the passenger compartment, in cargo compartments or engine fires, even though such fires were extinguished by the use of extinguishing agents.
• Multiple malfunctions of one or more aircraft systems seriously affecting the operation of the aircraft.
• Flight crew incapacitation in flight for single pilot operations (including remote pilot); or for multi-pilot operations for which flight safety was compromised because of a significant increase in workload for the remaining crew.
• Fuel quantity level or distribution situations requiring the declaration of an emergency by the pilot, such as insufficient fuel, fuel exhaustion, fuel starvation, or inability to use all usable fuel on board.
• Runway excursions
• System failures (including loss of power or thrust), weather phenomena, operations outside the approved flight envelope or other occurrences which caused or could have caused difficulties controlling the aircraft.
• Failures of more than one system in a redundancy system mandatory for flight guidance and navigation.
• The unintentional or, as an emergency measure, the intentional release of a slung load or any other load carried external to the aircraft.
• Aircraft structural failures or engine disintegrations, including uncontained turbine engine failures, not classified as an accident.
• Generally: events in which an aircraft received damage that necessitates repair or replacement of parts causing a grounding of at least two days.

Acts of Unlawful Interference:

• unlawful seizure of aircraft
• destruction of an aircraft in service
• hostage-taking on board aircraft
• forcible intrusion on board an aircraft, at an airport or on the premises of an aeronautical facility
• use of an aircraft in service for the purpose of causing death, serious bodily injury, or serious damage to property or the environment

Other occurrences:

• damage to parked aircraft due to weather phenomena (hurricanes, thunderstorms, floodings)

Examples of occurrences that are NOT covered in the ASN Database:

• Return to land for unclear 'technical' or 'operational' reasons
• Aircraft unable to retract gear after takeoff
• Passenger medical emergencies
• Stowaways
• False smoke or fire warnings
• Minor issues while parked or during taxi
• Bomb threats
• Damaged to aicraft that have been withdrawn from use or stored

Related

• Standards used on ASN (PDF)