Approximately 80 percent of all aviation accidents occur shortly
before, after, or during takeoff or landing, and are often described as
resulting from 'human error'; mid-flight disasters are rare but not entirely
unheard of. Among other things, the latter have been caused by bombs, as in
the 1988 Lockerbie incident, mid-air collisions such as in the 2002 Überlingen
crash and structural failure, as in the 1954 Comet disasters and 1988 Aloha
Airlines incident.
An accident survey of 1,843 aircraft accidents from 1950
through 2006 determined the causes to be as follows:
53%: Pilot error
21%: Mechanical failure
11%: Weather
6%: Sabotage (bombs, hijackings, shoot-downs)
8%: Other human error (air traffic controller error, improper
loading of aircraft, improper maintenance, fuel
contamination, language miscommunication etc.)
1%: Other cause