In the Canary Islands, airport operations have been disrupted due to a massive sandstorm that originated in the Sahara Desert. As a result, hundreds of travelers have been stranded.
But this situation pales in comparison to a collision between two commercial aircraft at Los Rodeos Airport (now known as Tenerife North Airport) on the island of Tenerife (the largest of the Canary Islands) on March 27, 1977.
The two-passenger planes which collided that day were KLM Flight 4805 (coming from the Netherlands) and Pam Am Flight 1736 (coming from Los Angeles after a stop in New York City). Both planes were headed to Gran Canaria International Airport on the island of Gran Canaria. However, due to a bomb being set off at Gran Canaria International Airport by the separatist group Canary Islands Independence Group (and the separatists warning that a second bomb would be set off), both flights were diverted to Los Rodeos, which at the time was just a regional airport that could not easily accommodate both planes and all the other aircraft being diverted there. Los Rodeos consisted of just one runway, one major taxiway, and four short taxiways.
Once the threat at Gran Canaria had been contained, all flights would soon be able to depart. The Pan Am plane was ready to do so, but access to the runway was blocked by the KLM plane and a refueling truck, and it took thirty-five minutes for the plane to be refueled. A family of four who were passengers on the KLM flight had to be located after the passengers boarded the plane, which caused a further delay.
To make matters worse, clouds had descended on the airport, creating a fog that reduced visibility. As a result, neither passenger plane would be able to see each other, nor would they be seen from the control tower.
The KLM flight would be the first plane to taxi down the runway, and then it would make a 180-degree turn in order to get into takeoff position. Once clearance was given for takeoff, the KLM flight could then depart.
The captain of the KLM flight, Jacob Louis Veldhuyzen van Zanten, was apparently anxious to get to Gran Canaria and return to the Netherlands that day. Regulations by the Dutch Government-imposed penalties for Dutch pilots who exceeded their flight hours for a given day (i.e. there were required rest periods in order to avoid pilot fatigue). Thus, he had to be concerned that Los Rodeos might close due to the fog, and have to get hotel rooms for himself, the crew, and the passengers. And considering he was one of the best pilots in the Netherlands, things would be embarrassing for him if the airport did close. In addition, having to return the following day would cause further delays for KLM.
It should be noted that van Zanten had trained many pilots, including the first officer that was part of the KLM crew that fateful day. In addition, this was van Zanten’s first flight in a while.
Once the KLM plane was in takeoff position, van Zanten had advanced the throttles and started to move the plane, but was told by the first officer that takeoff clearance had not been obtained. Perhaps frustrated by this fundamental mistake in the field of aviation, van Zanten told the first officer to get clearance for takeoff. Instructions from the control tower were given for what route the plane was to take, but no clearance was given.
Meanwhile, the Pam Am plane was taxiing down the runway as instructed and was attempting to exit the runway via the third taxiway. However, the flight crew became confused about whether they had been instructed to exit via the first taxiway or the third taxiway, and the controller clarified that they were to use the third taxiway. But due to the taxiways being unmarked (in addition to the fog and the fact that the Pam Am crew was unfamiliar with Los Rodeos), the Pam Am plane would wind up attempting to exit the runway via the fourth taxiway.
A series of miscommunications then took place because of simultaneous transmissions taking place between both planes and the control tower, which in turn led to interference on the radio frequency. As a result, van Zanten believed he was cleared for takeoff, and the KLM plane began heading down the runway. At the same time, the Pam Am plane had reached the fourth taxiway and was leaving the runway when its crew spotted the KLM plane accelerating towards them. Both crews tried to maneuver to avoid a collision, but to no avail. The KLM plane (which became airborne prior to the collision) wound up striking the upper right side of the Pam Am’s fuselage, thus tearing a portion out of the Pam Am. The KLM flight remained in the air for a moment before crashing into the ground and killing everyone on board. As for the Pam Am plane, there were 335 fatalities and 61 survivors.
An investigation conducted by both airlines as well as the American, Dutch, and Spanish Governments (since the Canary Islands are Spanish territory) took many factors into account, i.e. the terrorist attack, the fog, miscommunications. KLM eventually admitted van Zanten’s error and compensated the families of the victims.
As a result of the collision, improvements were made in the field of aviation, such as the use of standard air traffic instruction language, technological improvements, and team-making among the flight crew.
Such measures have made air travel a little safer.