Causes

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 ^[1] of 1,843 aircraft accidents from 1950 through 2006 determined the causes to be as follows:

• 21%: Mechanical failure
• 11%: Weather
• 8%: Other human error (air traffic controller error, improper loading of aircraft, improper maintenance, fuel contamination, language miscommunication etc.)
• 6%: Sabotage (bombs, hijackings, shoot-downs)
• 1%: Other cause

The survey excluded military, private, and charter aircraft.

A study by Boeing ^[2] determined the primary cause of Airline hull loss accidents (worldwide commercial jet fleet), from 1996 through 2005, to be:

• 55%: Flight crew error
• 17%: Airplane
• 13%: Weather
• 7%: Misc./Other
• 5%: Air traffic control
• 3%: Maintenance

That study included 183 accidents, with known causes for 134 of them. The remaining 49 were unknown, or awaiting final reports.

Previous Boeing studies showed higher rates for Flight Crew Error:

• 70%: 1988 - 1997
• 67%: 1990 - 1999
• 66%: 1992 - 2001

• 56%: 1995 - 2004

Aircraft manufacturers are often slow to accept that aspects of design might play a role in accident causation, finding it more convenient to state that human crew members were responsible. In fact, the complex interaction between the human crew and the aircraft often creates a fertile ground in which human error may flourish.^{[3][neutrality disputed]}