Tenerife airport disaster

On 27 March 1977, two Boeing 747 passenger jets collided on a runway at Los Rodeos Airport (now Tenerife North–Ciudad de La Laguna Airport) on the Spanish island of Tenerife. The crash happened in dense fog, and it became the deadliest accident in aviation history, with 583 people losing their lives and 61 others injured.

The two planes had landed earlier that day and were diverted to Los Rodeos because of a bomb explosion at their planned destination, Gran Canaria Airport. The airport was very busy, with many planes parked and limited space for planes to move. Thick fog made it hard for pilots and the control tower to see clearly.

Investigators found that a misunderstanding in radio communications between the pilots and air traffic control played a big role in the accident. This event led to important changes in how pilots communicate and work together during flights. It showed how crucial clear and standard communication is to keep everyone safe.

Flight history

Tenerife was an unscheduled stop for both flights. They were headed to Gran Canaria Airport, also called Las Palmas Airport or Gando Airport, which serves Las Palmas on the nearby island of Gran Canaria.

KLM Flight 4805

KLM Flight 4805 was a special flight for a travel group and had come from Amsterdam Airport Schiphol in the Netherlands. The plane was a Boeing 747 named Rijn (Rhine). It carried 14 crew members and 235 passengers, including 52 children. Most of the passengers were Dutch, with some from Germany, Austria, and America. After landing at Tenerife, one passenger chose not to get back on the plane, so 234 passengers stayed.

Pan Am Flight 1736

Pan Am Flight 1736 was also a special flight, organized by a Greek shipping company. It started at Los Angeles International Airport and stopped at New York City's John F. Kennedy International Airport. The plane was a Boeing 747 named Clipper Victor. It had 380 passengers, mostly older people, but it also carried two children. Almost all passengers were American, except for a few from Canada. They were going to join a cruise ship for a trip around the Mediterranean.

The new crew included Captain Victor Grubbs, First Officer Robert Bragg, Flight Engineer George Warns, and 13 flight attendants. Clipper Victor was a famous plane because it was the first Boeing 747 to fly a regular passenger flight. It had also been taken over by someone trying to control it once before, but that happened before this accident.

Accident

Both flights were normal until they reached the islands. At 13:15, a bomb exploded in the terminal of Gran Canaria Airport, injuring eight people. Because of the threat of another bomb, the airport was closed, and all flights were diverted to Los Rodeos Airport on Tenerife. The Pan Am crew wanted to wait until the airport reopened, but they were ordered to go to Tenerife.

Los Rodeos was a small airport that struggled to handle all the extra planes. It had only one runway and one main path next to it, with four short paths connecting them. While waiting for Gran Canaria to reopen, the planes took up so much space that they had to park on the long path, making it impossible for other planes to use it. Departing planes had to drive along the runway to get ready for takeoff, a process called a backtrack.

When Gran Canaria reopened, the Pan Am plane was ready to leave, but the runway was blocked by the KLM plane and a refueling vehicle. The KLM captain decided to refuel fully at Los Rodeos to save time. The refueling took about 35 minutes, and then passengers returned to the plane. The search for a missing Dutch family delayed the flight further. Because of these delays, Robina van Lanschot, a tour guide, decided not to fly with the KLM plane. She was the only person from that flight who survived because she stayed on Tenerife.

The tower told the KLM plane to drive the entire length of the runway and then turn around to get ready for takeoff. While the KLM plane was driving along the runway, the controller asked them to say when they were ready to copy the instructions. Because the crew was busy with their checklist, they postponed saying they were ready until they were in position for takeoff.

The Pan Am plane was told to follow the KLM plane down the same runway, take the third exit on the left, and then use the path next to the runway. The crew was unsure which exit to take because there were no signs or markings, and visibility was poor. They thought they had passed the first two exits but were unsure if they had reached the third exit when the collision happened.

The weather at Los Rodeos was tricky. Clouds at high altitudes were at ground level there, causing visibility to change quickly from clear to very poor. The collision happened in dense fog.

There were communication problems between the pilots and the controllers. The KLM captain started the takeoff without proper clearance. The controller told them to wait, but the KLM crew misunderstood and began taking off. At the same time, the Pan Am crew was still on the runway. The fog was so thick that neither crew could see the other plane, and the controller could not see either plane because the airport did not have ground radar.

As the KLM plane began its takeoff, the Pan Am captain saw the KLM's lights through the fog. He tried to avoid the KLM plane by turning sharply, but it was too late. The KLM plane, moving too fast to stop, hit the Pan Am plane. The KLM plane crashed shortly after, and a fire started immediately. One survivor from the Pan Am flight said that sitting in the front part of the plane likely saved his life.

Victims

Both airplanes were destroyed when they crashed into each other. All 248 people on the KLM plane sadly did not survive. On the Pan Am plane, 335 people did not survive, but 61 people were able to live through the accident. Many of those who survived were able to leave the airplane by walking on the left wing, which was not damaged in the crash.

The accident happened in thick fog, which made it hard for rescue teams to find both airplanes and help the survivors right away. Among those who did not survive were well-known people, such as a chief flight instructor for KLM and a famous film actress.

Many of the people who did not survive on the Pan Am plane were from Orange County, California, and were mostly retirees who were traveling together.

Aftermath

The next day, a group that had been involved in earlier events denied responsibility for the accident. The airport was closed for two days while recovery efforts took place. Help arrived by boat, and a military plane landed to help care for survivors and take them to hospitals.

Workers cleared the runway, and small planes could start flying again within a few days. The airport fully reopened about a week later after repairs were completed.

Investigation

The accident was studied by Spain's Civil Aviation Accident and Incident Investigation Commission. Many people worked on the investigation, including experts from the United States, the Netherlands, and the two airlines involved. They found that mistakes and misunderstandings happened before the accident.

The main reason for the accident was that the KLM captain started taking off before getting permission. He wanted to leave quickly because of airline rules and because the weather was getting worse. Other important reasons included thick fog that made it hard to see and radio messages that overlapped, making it difficult to hear.

Legacy

After this tragic event, many important changes were made to keep airplanes safe. The world decided that pilots and air traffic controllers needed to speak more clearly, especially using English, so everyone would understand each other better.

Pilots also started working more as a team. Now, even the most experienced pilots listen to their crew, and everyone can speak up if they think something isn’t right. This helps make sure safe decisions are made.

A second airport opened on the island of Tenerife in 1978, called Tenerife South Airport. This helped spread out the traffic and made travel safer for everyone.

Memorials

After the tragedy, memorials were created to honor those who were lost. In Amsterdam, there is a special resting place for the victims of the KLM plane. Another memorial stands in Westminster, California, in the United States.

Over time, families and friends came together to remember everyone affected. In 2007, a special monument called the International Tenerife Memorial 27 March 1977 was unveiled to mark the event and show respect for all those involved.

Documentaries

The Tenerife airport disaster has been shown in many TV shows, podcasts, and documentaries. Some of these include:

• Episode 1 of Survival in the Sky, titled "Blaming the Pilot" from 1996.
• Episode 12 of Seconds From Disaster, called "Collision on the Runway" from 2004.
• Episode 625 of PBS's NOVA, named "The Deadliest Plane Crash" from 2006.
• A PBS special called Surviving Disaster: How the Brain Works Under Extreme Duress from 2011, based on a book by Amanda Ripley.
• An episode of Destroyed in Seconds.
• Episode 133 (Season 16, Episode 03) of the Canadian TV series Mayday, titled "Disaster at Tenerife" from 2016, along with a special called "Crash of the Century" from 2005.
• Footage from the event appears in the documentary Days of Fury from 1979.
• Episode 5 of the Nebula series Under Exposure from 2023 by Neo.
• Episodes 1 and 2 of Series 5 of the Cautionary Tales podcast from 2025 by Pushkin Industries, hosted by Tim Harford.