Air traffic accidents



An aviation accident is roughly defined in the Convention on International Civil Aviation Annex 13 as 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, in which a person is fatally or seriously injured, the aircraft sustains damage or structural failure and/or the aircraft is missing or is completely inaccessible.

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

An accident in which the damage to the plane is such that it must be written off, or in which the plane is destroyed is often referred to as a hull loss accident.

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 through dynamically active technological means. Should this support fail, there is limited opportunity for a positive 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 the safest 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 dying in 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; he died testing The Hawk (September 20, 1899). Just as with Lilienthal, promising designs and ideas for motorized planes were scrapped after 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.

Plane crashes with large numbers of casualties set in with the early passenger flights of the 1920s. The yearly death toll of plane crashes exceeded 100 for the first time in 1928, and 1,000 for the first time in 1943. Since 1945, the number of deaths has fallen below 1,000 only twice, in 2004 and 2007.

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


 * 53%: Pilot error
 * 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  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
 * 62%: 1994 - 2003
 * 56%: 1995 - 2004

Trantolo & Trantolo concluded that some common causes of airplane accidents include :


 * Pilot error
 * Inclement weather
 * Engine failure
 * Mid-air collisions
 * Negligent maintenance
 * Instrument failure
 * Icing
 * Air traffic controller error
 * Improper loading of cargo
 * Defective onboard equipment
 * Fuel tank explosions

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.

Major disasters
The March 27, 1977, Tenerife disaster remains the deadliest accident in aviation history with the highest number of airliner passenger fatalities. In this disaster, 583 people died when a KLM Boeing 747 attempted take-off and collided with a taxiing Pan Am 747 at Los Rodeos Airport. Pilot error, communications problems, fog, and airfield congestion (due to a bombing and a second bomb threat at another airport) all contributed to this catastrophe.

The crash of Japan Airlines Flight 123 in 1985 is the single-aircraft disaster with the highest number of fatalities. 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 deadliest mid-air collision with the highest number of fatalities is the 1996 Charkhi Dadri mid-air collision involving Saudia Flight 763 and Air Kazakhstan Flight 1907 over Haryana, India, in 1996. The crash was mainly the result of the Kazakh pilot flying lower than the altitude for which his aircraft was given clearance. 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 deadliest aviation-related disaster of any kind with the highest number of total fatalities, including fatalities on both the aircraft and the ground, was the destruction of the World Trade Center in New York City on September 11, 2001 with the intentional crashing of American Airlines Flight 11 and United Airlines Flight 175. 2,998 people were killed, the vast majority being occupants of the World Trade Center Towers and emergency personnel responding to the disaster.

On September 1, 1983, a Soviet Sukhoi-15 shot down Korean Air Lines Flight 007 carrying 269 passengers and crew.

Iran Air Flight 655 was a civilian airliner shot down by US missiles on Sunday 3 July 1988, over the Strait of Hormuz killing all 290 passengers and crew aboard, including 66 children, ranking it seventh among the deadliest airliner fatalities.

Safety
Aviation safety has come a long way in over one hundred years of implementation. In modern times, two major manufacturers still produce heavy passenger aircraft for the civilian market: Boeing of the United States of America and the European company 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.

When measured on a passenger-distance calculation, air travel is the safest form of transportation available (when measured on a passenger-journey basis, buses are the safest form of transport. see http://www.numberwatch.co.uk/risks_of_travel.htm ). Trains have .04 deaths for every 100 million miles while air travel has .01 deaths for every 100 million miles traveled. Compared to the automobile, with .94 deaths per 100 million miles, both figures are 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 traveling by car and twice as safe as rail." 

A 2007 study by Popular Mechanics found that passengers sitting at the back of a plane are 40% more likely to survive a crash than those sitting in the front. 

Aircraft Crashes Record Office (ACRO)
The Geneva-based Aircraft Crashes Record Office (ACRO) compiles statistics on aviation accidents of aircraft capable of carrying more than six passengers, not including helicopters, balloons, or fighter airplanes. The ACRO announced that the year 2007 was the safest year in aviation since 1963 in terms of number of accidents. There had been 136 accidents registered (compared to 164 in 2006), resulting in a total of 965 deaths (compared to 1,293 in 2006). 2004 was the year with the lowest number of fatalities since the end of World War II, with 766 deaths. The year with most fatalities was 1972, with 3,214 deaths.

Annual Aviation Safety Review (EASA)
The European Aviation Safety Agency (EASA) is tasked by Article 15(4) of Regulation (EC) No 216/2008 of the European Parliament and of the Council of 20 February 2008 to provide a review of aviation safety on an annual basis.

The Annual Safety Review presents statistics on European and worldwide civil aviation safety. The statistics are grouped according to type of operation, for instance commercial air transport, and aircraft category, such as aeroplanes, helicopters, gliders etc. The Agency had access to accident and statistical information collected by the International Civil Aviation Organisation (ICAO). States are required, according to ICAO Annex 13 on Aircraft Accident and Incident Investigation, to report to ICAO information on accidents and serious incidents to aircraft with a maximum certificated take-off mass (MTOM) over 2250 kg. Therefore, most statistics in this review concern aircraft above this mass. In addition to the ICAO data, a request was made to the EASA Member States to obtain light aircraft accident data. Furthermore, data on the operation of aircraft for commercial air transport was obtained from both ICAO and the NLR Air Transport Safety Institute.

United States
In the United States, most civil aviation incidents are investigated by the National Transportation Safety Board (NTSB). When investigating an aviation disaster, NTSB investigators piece together evidence from the crash and determine the likely cause or causes. The NTSB will also investigate incidents which occur overseas in collaboration with local investigation authorities where the crash has involved a US-registered aircraft, or where there has been significant loss of American lives.

United Kingdom
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.

Canada
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 - marine, air, rail and pipeline.

Retirement of flight numbers
It is common for an airline to cease using the flight number after a fatal crash. This is not always the case; see, for example, Japan Airlines 123, American Airlines Flight 587, Aeroflot Flight 593, Aero Flight 311, Iran Air Flight 655, United Airlines Flights numbered 608, 624, and 823,755, and Aer Lingus Flight 712.

Lists of airliner accidents

 * by year
 * by airline
 * by location


 * by cause / in alphabetical order
 * Mid-air collisions


 * List of airship accidents
 * List of accidents and incidents involving general aviation (including chartered / non-scheduled passenger flights)

Lists of military aircraft accidents

 * List of accidents and incidents involving military aircraft
 * List of Coalition aircraft accidents and incidents during the Iraq War
 * List of Coalition aircraft crashes in Afghanistan
 * List of C-130 Hercules crashes

Air safety

 * Air safety
 * Australian Transport Safety Bureau (Australian investigation authority)
 * National Transportation Safety Board (U.S. investigation authority)
 * Air Accidents Investigation Branch (UK investigation authority)
 * Transportation Safety Board of Canada (Canada investigation authority)
 * Aviation archaeology

Aviation Authorities

 * ICAO
 * EASA
 * FAA
 * Civil Aviation Authority

Other

 * Accident analysis
 * Aircraft hijacking
 * Disaster
 * Fuel tank explosion and fuel tank inerting system
 * List of aircraft shootdowns
 * List of deaths by aircraft misadventure
 * List of people who died in aviation accidents and incidents
 * List of space disasters
 * List of airshow accidents
 * List of news aircraft crashes