Source: Aircraft Crashes Record Office, Geneva.
Like all modes of transportation, air transport is subject to accidents that can be due to human (67%) or technical (20%) causes, and rarely due to atmospheric conditions (6%). Since air accident statistics started to be systematically compiled, 54% of all accidents took place less than 10 km from an airport. 50% and 21% of all accidents took place during the landing and takeoff phases, respectively. The evolution of the yearly number of fatalities is quite revealing. Up to the early 1970s, the number of fatalities increased with some proportionality with the growth of air traffic. By the 1970s, in spite of substantial growth levels of air traffic, fatalities undertook a downward trend. This is jointly the outcome of better aircraft designs, improved pilot training, better navigation and control systems, as well as comprehensive accident management aiming at identifying the causes and then possible mitigation strategies.
For instance, on August 2, 1985, Delta Flight 191 from Fort Lauderdale ran into a developing thunderstorm and wind shear conditions on its final approach to Dallas / Fort Worth Airport (DFW). The strong and unstable winds forced the plane, a Lockheed L-1011, to hit the ground before the runway, resulting in 135 fatalities. An investigation of the cause of the accident incited substantial revisions in airport emergency procedures and upgrades in weather detection equipment. On June 1, 2009, Air France Flight 447, en route from Rio de Janeiro to Paris, crashed in the Atlantic Ocean, of the coast of Brazil. Temporarily defective air sensor speed readings due to ice accumulation and pilot error caused an aerodynamic stall that crashed the plane, resulting in 228 fatalities. After investigation, it was recommended better training concerning stall recovery at high altitudes and that planes be retrofitted with heated airspeed sensors. Therefore, the safety record of air transportation continues to improve.