On March 27, 1977, two Boeing 747 passenger jets collided on the runway at Los Rodeos Airport (now Tenerife North Airport), on the Spanish island of Tenerife, Canary Islands. The crash killed 583 people, making it the deadliest accident in aviation history. As a result of the complex interaction of organizational influences, environmental conditions, and unsafe acts leading up to this aircraft mishap, the disaster at Tenerife has served as a textbook example for reviewing the processes and frameworks used in aviation mishap investigations and accident prevention.
A bomb explosion at Gran Canaria Airport, and the threat of a second bomb, caused many aircraft to be diverted to Los Rodeos Airport. Among them were KLM Flight 4805 and Pan Am Flight 1736 – the two aircraft involved in the accident. At Los Rodeos Airport, air traffic controllers were forced to park many of the airplanes on the taxiway, thereby blocking it. Further complicating the situation, while authorities waited to reopen Gran Canaria, a dense fog developed at Tenerife, greatly reducing visibility. When Gran Canaria reopened, the parked aircraft blocking the taxiway at Tenerife required both of the 747s to taxi on the only runway in order to get in position for takeoff. The fog was so thick that neither aircraft could be seen from the other, and the controller in the tower could not see the runway or the two 747s on it. As the airport did not have ground radar, the controller could find where each airplane was only by voice reports over the radio. CHECK THE VIDEO HERE