The remains of the KLM 747 at Los Rodeos Airport, Santa Cruz de Tenrife, March 27, 1977.
On This Day: 583 Killed as 747s Collide on Tenerife Runway
The two 747s waited at Los Rodeos along with several other large planes until Las Palmas was reopened. The airport’s taxiways were overcrowded, forcing airporrt officials to use the lone runway as both a runway and a taxiway.
After several hours, Los Palmas was reopened, and the Pan Am and KLM planes prepared to take off. KLM 4805 went first, taxiing up the runway and turning around to take off. Pan Am 1736, meanwhile, was instructed to taxi halfway down the runway and park at a taxiway; however, pilot Victor Grubbs missed the intended taxiway and continued down the runway toward the next one.
Due to a misunderstanding with flight control, KLM pilot Jacob Veldhuyzen van Zanten decided to takeoff before receiving proper clearance. In a heavy fog, he was unable to see that Pan Am 1736 was still turning left into the taxiway.
“Roaring at full power, the KLM's hot engines (2000° F.) and massive landing gear crunched through the Pan Am's fuselage with such impact and explosive fire that aluminum and steel parts of both planes were vaporized,” wrote Time. “The KLM’s giant engine airlets sucked fragments of the Pan Am jet into its innards before crumpling into a molten mass 1,500 ft. past the point of impact.”
All 248 people aboard the KLM were killed, as were 335 of the 396 people aboard the Pan Am. With 583 fatalities, the Tenerife crash is the deadliest plane crash in history.
Since 1977, technological developments have also improved aircraft safety. Pilot Patrick Smith writes that most airports now have radar that allow controllers to see where planes are on the runways at all times, while some planes have satellite technology that enables them to see surrounding traffic. Lighting has also improved, which improves visibility and lessens the chance that a pilot would miss a turn as Grubbs did.