Aviation accidents and incidents



An aviation accident is an occurrence on board an aircraft resulting in injury or death to one or more persons. The U.S. National Transportation Safety Board definition of an aviation accident is as follows:
 * ''An occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked.

An aviation incident is an occurrence other than an accident, associated with the operation of an aircraft, which affects or could affect the safety of operations.

Other countries adopt a similar approach, although there are minor variations, such as to the extent of aviation-related operations on the ground, covered, as well as with respect to the thresholds beyond which an injury is considered serious or the damage is considered substantial. A hull-loss accident is one where the damage to the plane is such that it must be written off, or in which the plane is totally destroyed.

History


Since the birth of flight, aircraft have crashed, often with serious consequences. This is because of the unforgiving nature of flight, where a relatively insubstantial medium, air, supports a significant mass. Should this support fail, there is limited opportunity for a good outcome. Because of this, aircraft design is concerned with minimizing the chance of failure, and pilots are trained with safety a primary consideration. Despite this, accidents still occur, though statistically flying is nowadays an extremely safe form of transportation. In fact, the relative rarity of incidents, coupled with the often dramatic outcome, is one reason why they still make headline news. Nevertheless, while the odds of actually getting caught in a plane crash are nowadays distinctly low compared to other means of transportation, the chances of not surviving such a disaster are notably higher.

Many early attempts at flight ended in failure when a design raised to a height for a launch would fail to generate enough lift and crash to the ground. Some of the earliest aviation pioneers lost their lives testing aircraft they built.

Otto Lilienthal died after a failure of one of his gliders. On his roughly 2,500th flight (August 9, 1896), he stalled in a gust of wind, causing him to fall from a height of roughly 56 ft (17 m), fracturing his spine. He died the next day, with his last words being reported as Opfer müssen gebracht werden! ("sacrifices must be made").

Percy Pilcher was another promising aviation pioneer. Pilcher died testing The Hawk (September 20, 1899). Just as with Lilienthal, promising designs and ideas for motorized planes were lost with his death. Some other early attempts experienced rough landings, such as Richard Pearse who is generally accepted to have crash landed (survived) a motorized aircraft in some bushes, unable to gain altitude after launching it from some height.

The [Wright Flyer nearly crashed on the day of its historic flight, sustaining some damage when landing. Three days before, on a previous flight attempt, Wilbur Wright overcontrolled the aircraft in pitch and crashed it on takeoff, causing minor damage in the first known case of pilot-induced oscillation.

US Army Lt. Thomas Selfridge became the first person killed in a powered fixed-wing aircraft on September 17, 1908 when his aircraft, piloted by Orville Wright, crashed after propeller separation failure during military tests at Fort Myer in Virginia. Selfridge died of a fractured skull. Wright suffered broken ribs, pelvis and a leg.

Causes


Approximately 80 percent of all aviation accidents occur shortly before, after, or during takeoff or landing, and are typically the result of human error and/or unregarded technical problems within an aircraft; 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, structural failure as in the 1954 Comet disasters and 1988 Aloha Airlines incident, or in cases of (purportedly) mistaken identity where civilian aircraft were shot down by military (compare Korean Air Flight 007).

An accident survey of 2,147 aircraft accidents from 1950 through 2004 determined the causes to be as follows:


 * 45%: Pilot error
 * 33%: Undetermined or missing in the record
 * 13%: Mechanical failure
 * 7%: Weather
 * 5%: Sabotage (bombs, hijackings, shoot-downs)
 * 4%: Other human error (air traffic controller error, improper loading of aircraft, improper maintenance, fuel contamination, language miscommunication etc.)
 * 1%: Other cause

The survey excluded military, private, and charter aircraft.

A study by Boeing  (page 19) 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%: ATC
 * 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
 * 62%: 1994 - 2003
 * 56%: 1995 - 2004

Major Disasters
The March 27, 1977 Tenerife Disaster remains the worst accident in aviation history. In this disaster, 583 people died when a KLM Boeing 747 attempted take-off without clearance and collided with a taxiing Pan Am 747 at Los Rodeos Airport. Pilot error, communications problems, fog, and airfield congestion (due to a bomb threat at another airport) all contributed to this catastrophe.

The crash of Japan Airlines Flight 123 in 1985 is the worst single-aircraft disaster. In this crash 520 died on board a Boeing 747. The aircraft suffered an explosive decompression which destroyed its vertical stabilizer and severed hydraulic lines, making the 747 virtually uncontrollable.

The world's biggest mid-air collision, Saudia Flight 763/Air Kazakhstan Flight 1907 crash over Haryana, India in 1996 was mainly the result of the Saudia pilot flying higher than the altitude his aircraft was given clearance for. 349 passengers and crew died from both aircraft. The Ramesh Chandra Lahoti Commission, empowered to study the causes, also recommended the creation of "air corridors" to prevent planes from flying in opposite directions at the same altitude.

The worst aviation-related disaster of any kind was the destruction of the World Trade Center in New York City on September 11, 2001 after the intentional crashing of American Airlines Flight 11 and United Airlines Flight 175. 2,749 people were killed, mostly occupants of the destroyed buildings and rescue workers.

Safety
Aviation safety has come a long way in over one hundred years of implementation. In modern times, two major aircraft manufacturers still co-exist: Boeing of the United States of America and the European Airbus. Both have placed huge emphasis on the use of aviation safety equipment, now a billion-dollar industry in its own right, and made safety a major selling point -- realizing that a poor safety record in the aviation industry is a threat to corporate survival. Some major safety devices now required in commercial aircraft involve:
 * Evacuation slides - aid rapid passenger exit from an aircraft in an emergency situation.
 * Advanced avionics - Computerized auto-recovery and alert systems.
 * Turbine Engine durability improvements
 * Landing gear that can be lowered even after loss of power and hydraulics.

Air travel is the safest form of transportation available. Trains have .04 deaths for every 100 million miles while air travel has .01 deaths for every 100 million miles travelled. However, compared to the automobile, with .94 deaths per 100 million miles, both figures are relatively low. According to the BBC: "UK airline operations are among the safest anywhere. When compared against all other modes of transport on a fatality per mile basis air transport is the safest - six times safer than travelling by car and twice as safe as rail." 

The NTSB
In the United States, many civil aviation incidents have been investigated by the National Transportation Safety Board. When investigating an aviation disaster, NTSB investigators piece together evidence from the crash and determine the likely cause(s).

The AAIB
In the United Kingdom, the agency responsible for investigation of civilian air crashes is the Air Accidents Investigation Branch (AAIB) of the Department for Transport. Its purpose is to establish the circumstances and causes of the accident and to make recommendations for their future avoidance.

The BST/TSB
The Transportation Safety Board of Canada (BST/TSB), an independent agency which reports directly to Parliament, is the Canadian agency responsible for the advancement of transportation safety through the investigation and reporting upon accident and incident occurrences in all prevalent Canadian modes of transportation - air, marine, rail and pipeline.

Lists of commercial airliner accidents

 * Grouped by airline
 * Grouped by location
 * Grouped by year
 * Grouped by cause (see subcategories)
 * Grouped alphabetically
 * Notable mid air collisions

Lists of military aircraft accidents

 * List of notable incidents and accidents on military aircraft
 * List of Coalition aircraft crashes in Iraq
 * List of aircraft shootdowns

Air safety

 * Air safety
 * National Transportation Safety Board (US investigation authority)
 * Air Accidents Investigation Branch (UK investigation authority)
 * Transportation Safety Board of Canada (Canada investigation authority)
 * Aviation archaeology

Other

 * Disaster
 * Aircraft hijacking
 * List of deaths by aircraft misadventure
 * List of people who died in aviation-related incidents
 * List of space disasters
 * Accident Analysis