On March 27, 1977, two Boeing 747 aircraft, one operated by KLM, the other by Pan Am, collided on a foggy runway at Los Rodeos Airport on the Spanish Island of Tenerife, one of the Canary Islands.
The crash remains today the deadliest accident in the history of aviation.
The aircraft involved in the Tenerife airport disaster were diverted to Tenerife from Gran Canaria Airport after a bomb exploded there. In Tenerife, controllers were forced to park arriving aircraft on the taxiway, thereby blocking it from further use. To make matters far worse, while local authorities were waiting to reopen Gran Canaria Airport, a thick fog developed in Tenerife, obstructing visibility to nothing.
When Gran Canaria Airport was secured and reopened to traffic, the parked aircraft on the taxiway at Los Rodeos Airport prevented the Boeing 747s from using the taxiway to access the departure point on the single runway at Los Rodeos, forcing both aircraft to backtrack on the runway to reach position for takeoff. Due to the foggy conditions, however, neither aircraft could see the other, nor could the air traffic controllers see the aircraft on the airfield. The airport was not equipped with ground radar either, thus creating a situation where the only means of communicating information to the crews was through verbal transmissions.
As a result of several misunderstandings in the ensuing verbal communications, as well as a fair amount of poor decision-making, the KLM flight attempted to depart while the Pan Am flight was still on the runway. The resulting collision destroyed both aircraft, killing all 248 aboard the KLM flight and 335 aboard the Pan Am flight. Sixty-one people aboard the Pan Am flight, including the pilots and flight engineer, survived the disaster. In total, 583 people perished in the crash.
Like most accidents in recent aviation history, the Tenerife Airport Disaster resulted in widespread changes to the industry, most notably in this case in the areas of communications and flight crew resource management.
Today on the anniversary of this tragic event, we mourn the loss of those who perished in the crash.