520 : The crash of Japan Airlines Flight 123 on August 12 , 1985 , is the single-aircraft disaster with the highest number of fatalities : 520 people died on board a Boeing 747 . The aircraft suffered an explosive decompression from an incorrectly repaired aft pressure bulkhead , which failed in mid flight , destroying most of its vertical stabilizer and severing all of the hydraulic lines , making the 747 virtually uncontrollable . Pilots were able to keep the plane flying for 32 minutes after the mechanical failure before crashing into a mountain . All 15 crew members and 505 of the 509 passengers on board died . Rescue operations were delayed until the following morning , which likely decreased the number of victims who would have survived the incident . Furthermore , Japanese personnel inaccurately assumed , during a helicopter flyover of the impact site , that there were no survivors . Medical providers involved in rescue and analysis operations determined that several passengers likely survived the impact and probably would have survived the incident had rescue operations not been delayed . Four passengers survived the incident in its entirety ; meaning that they were alive when discharged from the hospital
Japan Airlines Flight 123
Japan Airlines Flight 123
Aviation accidents and incidents