Collision Site - Pan Am 1736 & KLM 4805 | crash site, aircraft crash site

 crash site, aircraft crash site

On the morning of March 27, 1977, a terrorist bomb exploded in a flower shop of the airport at Las Palmas, on the island of Gran Canaria. Authorities closed the airport and diverted all incoming traffic to nearby Tenerife. On this Sunday, Tenerife quickly became overwhelmed not only with the volume of aircraft, but with the size of many of the airplanes, which the tarmac and terminal were not designed to handle.

Among the two planes inbound to Gran Canaria were a KLM 747 from Amsterdam and a Pan Am 747 from NYC and LAX. Both crews, afraid of overwhelming the airport and anxious not be delayed, requested permission to wait in a holding pattern. Both were denied. Along with all other inbound planes, they landed on runway 30 and taxied to the tarmac.

Unfortunately, the Pan Am plane landed first, and was boxed in by the later arriving KLM 747. The KLM crew, anxious to beat a work-limit deadline, decided to refuel at Tenerife, hoping to avoid the expected long refueling line at Gran Canaria of all the diverted planes. The Pan Am crew, realizing they were blocked in, got out and physically measured the space on the tarmac, and found they would have needed a mere 10-20 feet to get around the KLM plane. They were stuck, and had to wait until the KLM plane finished and moved first.

When Gran Canaria announced it was open for traffic again, most (but not all) of the planes that landed before the KLM and Pan Am 747's took off without incident. The KLM plane taxied down the runway itself to the threshold of runway 30 and nervously awaited departure clearance. This time it was their turn to wait, as the Pan Am 747 was also required to use the runway to get to the take-off point. However, their instructions were to use only part of the runway and exit the runway at the third taxiway.

At the time, the taxiways were not marked, and confusion existed as to which one was the third. Keep in mind, the first three are 135 degree turns, which for a 747 is like getting an elephant to walk a tightrope - it's possible for a 747, but EXTREMELY difficult, as a slight wrong turn could end up with a stuck airplane and 350+ stranded passengers. Adding to it, there would have been not one, but TWO of these turns.

To make things worse, it was at that moment fog started to roll in, obscuring visibility. Not only did the control tower lose sight of both planes, but both planes lost sight of each other. Now the Pan Am plane was literally rolling down the runway blind, trying to figure out where its correct exit was. Add to this the fact that there was only one traffic controller on duty at Tenerife, and he was completely overwhelmed. This might not have been a problem had fog not rolled in obscuring visibility, but as it was, he had to rely on the airplanes themselves reporting their positions instead of being able to confirm it with his own eyes.

Directly after the third taxiway the Pan Am crew saw the fourth, and at a 45 degree turn (which is MUCH easier to deal with), they assumed this was their intended exit, and they began their turn-off.

Meanwhile, the KLM plane anxiously awaited their take-off clearance. Desperate to avoid getting stuck at Gran Canaria or Tenerife because of duty-hour limitations, they had calculated they would have just enough time to land at Gran Canaria, disembark their passengers, and return to Amsterdam - and the sooner they could get away from Tenerife, the more of a safety margin they would have. In addition, there was the fact that the flight crew was commanded by Captain Jacob van Zanten - KLM's chief training pilot and one of the most senior crew members. Ironically, he had spent most of the last few years training other pilots, and might not have been familiar with the intricacies of modern cockpit teamwork. The junior crew members would also have been very apprehensive about questioning or second-guessing his decisions.

At this point, the KLM plane stood ready, and requested its take-off clearance. The tower gave them their departure clearance, but not their permission to take-off. The Pan Am plane tried to break in and let both parties know that they were still on the runway, but because of an overlap in radio communications, the message was not received.

It can never be known for sure, but it is surmised that Captain Van Zanten believed he had permission to begin his take-off run, when in reality he only had permission to fly the the flight plane he had filed to Gran Canaria (that he could fly AFTER he received his separate take-off permission). And thus, the take-off roll began...with the Pan Am 747 still on the runway, but obscured by fog.

Too late, both flight crews saw each. The Pan Am crew increased power in a desperate attempt to clear the runway, and the KLM crew rotated the plane early hoping to leap over the Pan Am plane blocking the runway. The KLM plane - extra heavy from the fuel they filled up with - actually rotated early, scraping the bottom of the plane in the process. It became airborne just before the Pan Am 747...

But not soon enough to clear the Pan Am plane. The left outboard engine of the KLM 747 struck the vertical stabilizer of the Pan Am 747, the right outboard engine took out the cockpit, and the landing gear hit the center of the fuselage. The KLM plane remained airborne for a few more seconds and then slammed back to the ground, exploding on impact and rotating 90 degrees. There were no survivors.

The Pan Am plane rolled to a stop, and a few passengers and crew had the opportunity to escape. However, the majority of the Pan Am passengers were trapped by the collapsing fuselage and fire from the ruptured fuel tanks and were unable to escape. In the end, there were only 59 survivors.

IF the bomb hadn't gone off at Gran Canaria, no planes would have been diverted, and the collision wouldn't have occured.

IF the KLM plane had landed first, the Pan Am plane would have been able to take off sooner, and the collision wouldn't have occured.

IF the KLM plane hadn't refueled, it would have been lighter, and would have cleared the Pan Am 747, and the collision wouldn't have occured.

IF the fog hadn't rolled in, the KLM crew would have seen the Pan Am plane still on the runway and wouldn't have begun their take-off run prematurely, and the collision wouldn't have occured.

IF the Pan Am crew had turned off at the third taxiway instead of the fourth, they would have been clear of the runway in time for the KLM plane to take-off safely, and the collision wouldn't have occured.

IF one of the KLM crew members had questioned Captain Van Zanten's authority and double-checked with the tower to see if they had permission to take-off instead of acquiesing to his determination to meet their time deadline, they would have heard from the Pan Am plane that they were still on the runway, and the collision wouldn't have occured.

So many if's - but lessons have been learned so that all the souls lost did not die completely in vain.

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