Distribution of Accidents
by Accident Category
Definition of accident categories
The accident categories described are based on standard ICAO definitions. The seven categories listed below are the accident types that are the cause of most accidents.
CONTROLLED FLIGHT INTO TERRAIN (CFIT)
In-flight collision with terrain, water, or obstacle without indication of loss of control.
ABNORMAL RUNWAY CONTACT (ARC)
Any takeoff or landing involving abnormal runway contact, and not primarily due to SCF, leading to an accident. Hard landings and tail strikes are included in this category.
LOSS OF CONTROL IN-FLIGHT (LOC-I)
Loss of aircraft control while in flight, and not primarily due to SCF.
SYSTEM/COMPONENT FAILURE OR MALFUNCTION (SCF)
Failure or malfunction of an aircraft system or component, related to its design, the manufacturing process, or a maintenance issue, which leads to an accident. SCF includes those related to powerplant (SCF-PP) and those which are not powerplant-related (SCF-NP).
RUNWAY EXCURSION (RE)
A lateral veer-off or longitudinal overrun off the runway surface, and not primarily due to SCF or ARC.
UNDERSHOOT/OVERSHOOT (USOS)
Touchdown off the runway surface in close proximity to the runway. It includes offside touchdowns.
FIRE (F-NI AND F-POST)
Fire or smoke inside or outside of the aircraft, in flight or on the ground, and regardless of whether the fire results from an impact (F-POST) or not (F-NI).
The leading cause of fatal accidents over the last 20 years was the Loss Of Control In-flight (LOC-I)
LOC-I accidents have significantly reduced for generation 4 aircraft enabled by fly-by-wire technologies.
CFIT accidents are the second largest category of accidents. The number of these accidents is decreasing with the continued development of navigation and Terrain Awareness and Warning System (TAWS) technologies, which are available on both generation 3 and generation 4 aircraft.
Runway Excursions (RE), including lateral and longitudinal types, are the third major cause of fatal accidents and the primary cause of hull losses. Emerging technologies, both energy based and performance based, show promising trends for preventing longitudinal RE accidents.
Evolution of the Main Accident Categories
10 year moving average hull loss accident rate (per million flights) per accident category
