The Tenerife Disaster (1977)
On March 27, 1977, two Boeing 747 passenger jets, KLM Flight 4805 and Pan Am Flight 1736, collided on the runway at Los Rodeos Airport (now Tenerife North Airport), on the Spanish island of Tenerife, Canary Islands, killing 583 people, making it the deadliest accident in aviation history.
A terrorist incident at Gran Canaria Airport had caused many flights to be diverted to Los Rodeos, including the two aircraft involved in the accident. The airport quickly became congested with parked airplanes blocking the only taxiway and forcing departing aircraft to taxi on the runway instead. Patches of thick fog were drifting across the airfield, so that the aircraft and control tower were unable to see one another.
The collision occurred when the KLM airliner initiated its takeoff run while the Pan Am airliner, shrouded in fog, was still on the runway and about to turn off onto the taxiway. The impact and resulting fire killed everyone on board KLM 4805 and most of the occupants of Pan Am 1736, with only 61 survivors in the front section of the aircraft.
The subsequent investigation by Spanish authorities concluded that the primary cause of the accident was the KLM captain’s decision to take off in the mistaken belief that a takeoff clearance from air traffic control (ATC) had been issued. Dutch investigators placed a greater emphasis on mutual misunderstanding in radio communications between the KLM crew and ATC, but ultimately KLM admitted that their crew was responsible for the accident and the airline agreed to financially compensate the relatives of all of the victims.
The disaster had a lasting influence on the industry, highlighting in particular the vital importance of using standardized phraseology in radio communications. Cockpit procedures were also reviewed, contributing to the establishment of crew resource management as a fundamental part of airline pilots’ training.
Tenerife was an unscheduled stop for both flights. Their destination was Gran Canaria International Airport (also known as Las Palmas Airport or Gando Airport), serving Las Palmas on the nearby island of Gran Canaria. Both islands are part of the Canary Islands, an autonomous community of Spain located in the Atlantic Ocean off the southwest coast of Morocco.
KLM Flight 4805
KLM Flight 4805 was a charter flight for Holland International Travel Group and had arrived from Amsterdam Airport Schiphol, Netherlands. Its cockpit crew consisted of captain Jacob Veldhuyzen van Zanten, age 50, first officer Klaas Meurs, age 42, and flight engineer Willem Schreuder, age 48. At the time of the accident, van Zanten was KLM’s chief flight instructor, with 11,700 flight hours, of which 1,545 hours were on the 747. Meurs had 9,200 flight hours, of which 95 hours were on the 747. Schreuder had 15,210 flight hours, of which 540 hours were on the 747.
The aircraft was a Boeing 747-206B, registration PH-BUF, named Rijn (Rhine). The KLM jet was carrying 14 crew members and 235 passengers, including 52 children. Most of the KLM passengers were Dutch; also on board were 4 Germans, 2 Austrians and 2 Americans. After the aircraft landed at Tenerife, the passengers were transported to the airport terminal. One of the inbound passengers, who lived on the island with her boyfriend, chose not to re-board the 747, leaving 234 passengers on board.
Pan Am Flight 1736
Pan Am Flight 1736 had originated at Los Angeles International Airport, with an intermediate stop at New York’s John F. Kennedy International Airport (JFK). The aircraft was a Boeing 747-121, registration N736PA, named Clipper Victor. Of the 380 passengers (mostly of retirement age, but including two children), 14 had boarded in New York, where the crew was also changed. The new crew consisted of captain Victor Grubbs, age 56, first officer Robert Bragg, age 39, flight engineer George Warns, age 46, and 13 flight attendants. At the time of the accident, Grubbs had 21,043 hours of flight time, of which 564 hours were on the 747. Bragg had 10,800 flight hours, of which 2,796 hours were on the 747. Warns had 15,210 flight hours, of which 559 hours were on the 747.
This particular aircraft had operated the inaugural 747 commercial flight on January 22, 1970. On August 2, 1970, in its first year of service, it also became the first 747 to be hijacked: en route between JFK and Luis Muñoz Marín International Airport in San Juan, Puerto Rico it was diverted to José Martí International Airport in Havana, Cuba.
Diversion of aircraft to Los Rodeos
Both flights had been routine until they approached the islands. At 13:15, a bomb planted by the separatist Canary Islands Independence Movement exploded in the terminal of Gran Canaria International Airport, injuring eight people. There had been a phone call warning of the bomb, and another call received soon afterwards made claims of a second bomb at the airport. The civil aviation authorities had therefore closed the airport temporarily after the explosion, and all incoming flights bound for Gran Canaria had been diverted to Los Rodeos, including the two Boeing 747 aircraft involved in the disaster. The Pan Am crew indicated that they would prefer to circle in a holding pattern until landing clearance was given, but they were ordered to divert to Tenerife.
Los Rodeos was a regional airport that could not easily accommodate all of the traffic diverted from Gran Canaria, which included five large airliners. The airport had only one runway and one major taxiway running parallel to it, with four short taxiways connecting the two. While waiting for Gran Canaria airport to reopen, the diverted airplanes took up so much space that they were having to park on the long taxiway, making it unavailable for the purpose of taxiing. Instead, departing aircraft needed to taxi along the runway to position themselves for takeoff, a procedure known as a backtaxi or backtrack.
The authorities reopened Gran Canaria airport once the bomb threat had been contained. The Pan Am plane was ready to depart from Tenerife, but access to the runway was being obstructed by the KLM plane and a refueling vehicle; the KLM captain had decided to fully refuel at Los Rodeos instead of Las Palmas, apparently to save time. The Pan Am aircraft was unable to maneuver around the refueling KLM, in order to reach the runway for takeoff, due to a lack of safe clearance between the two planes, which was just 3.7 meters (12 ft). The refueling took about 35 minutes, after which the passengers were brought back to the aircraft. The search for a missing Dutch family of four, who had not returned to the waiting KLM plane, delayed the flight even further. A tour guide had chosen not to reboard for the flight to Las Palmas, because she lived on Tenerife and thought it impractical to fly to Gran Canaria only to return to Tenerife the next day. She was therefore not on the KLM plane when the accident happened, and she would be the only survivor of those who flew from Amsterdam to Tenerife on Flight 4805. Read More…..