The deadliest aviation accident in history occurred on March 27, 1977, at Los Rodeos Airport (now Tenerife North Airport) on the island of Tenerife, Canary Islands. Known as the Tenerife Airport Disaster, it involved a collision between two Boeing 747s—KLM Flight 4805 and Pan Am Flight 1736—on a fog-shrouded runway. The tragedy resulted in the deaths of 583 people. The crash was caused by a catastrophic chain of events, including heavy fog that blinded the control tower, a bomb at a nearby airport that diverted both planes to the smaller facility, and a critical miscommunication that led the KLM pilot to take off while the Pan Am jet was still taxiing on the same runway. This event fundamentally changed global aviation, leading to the creation of "Crew Resource Management" (CRM) and the requirement for standardized English terminology between all pilots and controllers to prevent similar linguistic confusion.