Accident Occurrence Categories by CICTT Definition
The CAST/ICAO Common Taxonomy Team (CICTT) provides definitions for aviation occurrence categories. For each of the accidents, where possible, one or more CICTT occurrence categories were allocated and these are shown for the 2024 events here. In some cases, more than one occurrence category is applied to a single accident.
The figure below shows the breakdown of all 64 Western OEM accidents by CICTT occurrence categories. The same breakdown is shown in the figure further below, but only for the 29 fatal accidents.
CICTT Occurrence Categories for All Accidents 2013-2024 (n=64)
Based on this analysis, the two largest occurrence categories associated with all accidents are loss of control in flight (LOC-I = 23%) and non-powerplant system or component failures (SCF-NP = 23%), followed by collision with obstacle(s) on take-off and landing (CTOL = 10%) and controlled flight into terrain or water (CFIT = 8%). The ‘Other’ category here contains 10 different causes, each with a proportion of 5% or less.
Changing focus to only fatal accidents changes this breakdown; the figure below shows the proportion of occurrence categories associated with fatal accidents only.
CICTT Occurrence Categories for Only Fatal Accidents 2013-2024 (n=29)
The figure shows loss of control in-flight is the associated with a third of fatal accidents (LOC-I = 33%) followed by controlled flight into terrain or water (CFIT = 21%) and non-powerplant system or component failures (SCF-NP = 17%). Here ‘Other’ contains 3 categories each with a proportion of 5% or less.
These occurrence categories correlate with the HeliOffshore Safety Performance Model focus areas of:
Aircraft Upset;
Surface / Obstacle Conflict; and
System Failure.