• Distribution of accidents by accident category

Definition of accident categories

Aviation organisations define more than 40 different accident categories. However the five listed below are the individual types which cause the most significant number of accidents.


In-flight collision with terrain, water, or obstacle without indication of loss of control.


Loss of aircraft control while in flight not primarily due to SCF.


A lateral veer off or longitudinal overrun off the runway surface, not primarily due to SCF or ARC.


Hard or unusual landing,  not primarily due to SCF, leading to an accident.


Failure or malfunction of an aircraft system or component, related to either its design, the manufacturing process or a maintenance issue, which leads to an accident. SCF includes the powerplant, software and database systems.

The single biggest cause of fatal accidents over the last 20 years is LOC-I

LOC-I accidents have been shown to be significantly reduced by technologies already existing on fourth generation aircraft.

CFIT accidents continue to be reduced in number thanks to the availability and continued development of glass cockpit and navigation technologies available on both third and fourth generation aircraft.

Runway Excursions (RE) including both lateral and longitudinal types, are the third major cause of fatal accidents by numbers, and the single biggest cause of hull losses. Emerging technologies (energy-based and performance-based) are very promising for addressing longitudinal events.

Percentage of fatal accident by accident category 1999-2018

Percentage of fatal accidents by accident category 1999-2018

Percentage of hull losses by accident category 1999-2018

Percentage of hull losses by accident category 1999-2018

Impact of technology on aviation safety

Comparison of accident rates by generation of aircraft provides a clear illustration of the value of our industry’s investments in technology for Safety.

Studying the statistics over the life of each generation of jets shows that an 85% reduction in fatal CFIT accidents has been achieved between the second and third generation of jets. In addition to this achievement, the fourth generation of jets has added a 75% reduction in fatal LOC-I accidents compared to the third generation. These are great achievements,  which we can properly put into context by studying the overall reduction in  the fatal accident rate per generation.

The lowest sustained fatal accident rate of first generation jets was around 3.0 accidents per million flights, whilst for the second generation it was around 0.7, meaning a reduction of fatal accidents of almost 80% between generations. In comparison, third generation jets now achieve about 0.2 accidents per million flights, a reduction of around a further 70%. 

Finally, fourth generation jets have the lowest accident rate of all, at a stable average rate of about 0.1 fatal accidents per million flights, which is a further 50% reduction compared to the third generation.

Average fatal accident rate by accident category 1958-2018

Average fatal accident rate by accident category 1958-2018