March 27, 1977

On March 27, 1977 on the island of Las Palmas de Gran Canaria, a bomb threat was called in to the airport. It was later determined that this was a false threat, however, little did anyone realize the tragic chain of events that would be unleashed by this seemingly minor event.

Pan American Airlines flight 1736, a Boeing 747 carrying 380 passengers plus crew, had departed New York, heading for Las Palmas. At the same time KLM flight 4805, also a Boeing 747 carrying 234 passengers plus crew, from Schipol in the Netherlands was also heading to Las Palmas. Both flights arrived over the island only to be told that the airport was closed due to the bomb threat. Pan Am 1736 requested permission to orbit the airport until it was reopened, but was ordered to divert with KLM, and several other flights, to Rodeos.

The airport at Rodeos was way too small to handle such large airplanes. The airport consists of one runway, with a parallel taxiway, and several smaller taxiways connecting them. It was at Rodeos that the rest of many minor incidents would come together into the largest tragedy ever in the history of aviation.

Once on Rodeos, after the airport at Las Palmas was reopened, the Pan Am flight was ready to depart, however they were blocked in by the KLM flight, which was refueling. The KLM flight, piloted by KLM's chief training pilot at the time, Captain Jacob Veldhuyzen van Zanten. He was considered a very famous pilot in the Netherlands at the time, having filmed several commercials for KLM. He had been flying planes since 1947, and with KLM since 1951. He had accrued 12,000 flight hours and 1500 in 747s. However, most of the time he was either in the simulator, or training other pilots. He apparently chose to refuel on Rodeos instead of Las Palmas to save time.

The first major problem that arose that day was the decision for the KLM crew to either remain overnight on Rodeos, and force the airline to pay for hotels, or risk breaking Dutch law and going overtime on their crew duty day. In the Netherlands, it's a criminal offense for a pilot to be on duty for longer than 15 hours. This includes time on the ground. If the crew waited for the airport on Las Palmas to reopen, they would risk breaking that law. However, the decision to wait for Las Palmas to reopen was made.

After refueling, the KLM crew was told that Las Palmas would be reopening soon, and planes were going to be allowed to depart Rodeos. The KLM flight was given permission to taxi down the runway, and perform a 180 degree turn, lining them up for departure. Pan Am 1736 was cleared to taxi down the runway, turning off at the third taxiway, and moving down the taxiway to the end of the runway, to await KLM's departure. As the flights were taxiing a heavy fog rolled in, blanketing the area. As the KLM flight was moving down the runway, they received their Air Traffic Control clearance to Las Palmas. This clearance was ONLY for the flight, NOT for takeoff, as Pan Am 1736 was moving down the runway behind them.

Pan Am 1736, upon reaching taxiway C3 chose to continue to C4 instead of turning off the runway. To turn off at C3 would require two 135 degree turns, which in a plane the size of the 747 would be almost impossible. Taxiway C4 on the other hand was a much shallower turn off and would be possible to take.

Sometime around this time, the KLM flight having received their ATC clearance, began to take off. The copilot called the control tower and said they were taking off. At this point, the tower called them to tell them to stand by, and Pan Am 1736 called to say they were on the runway. The KLM flight engineer asked if they were clear of the runway. The control tower called Pan Am 1736 and told them to report clear of the runway. The Pan Am replied with "Roger, we will report clear." This was the last transmission made by the Pan Am crew. The flight engineer on the KLM flight again asked if Pan Am was clear of the runway. A few seconds later the Pan Am crew saw the taxi lights of the KLM, and realized they were shaking, which meant the plane was moving. The captain of the Pan Am attempted to turn off and go through the grass to get off the runway. At about the same time the KLM crew realized that the Pan Am flight was still on the runway. Capt van Zanten desperately tried to get the plane into the air, and did suceed in getting airborne, but the landing gear and belly of his plane hit the Pan Am 747 on the center of the fuselage, just over the wing. Both planes burst into flame, with the KLM crashing back to the runway and exploding killing everyone on board instantly. 321 passengers and 14 crew on Pan Am 1736 were killed in the explosion and fire. 54 passengers, and 7 crew survived, including all three flight deck crew members. There were a total of 583 people killed in the crash.

Several factors that were looked at included miscommunications between the tower and both planes, missed radio calls, bad weather, and Capt van Zanten's impatience to take off due to the fact that if they were forced to stay it would cost KLM to put up the passengers overnight. One of the things speculated on was Capt van Zanten's experience as chief instructor pilot for KLM. It is believed that he had come to view his role as instructor as him being right when he told the pilots he was training something.

After the NTSB and Spanish accident reports were released, the Dutch government launched their own investigation. The NTSB and Spanish investigators placed the blame almost entirely on the KLM flight crew, with some blame being placed on the control tower, and communication problems. The Dutch report went the entire opposite direction, and said the KLM crew had done absolutely nothing wrong, was following procedures, and the PAN AM crew had been the cause of the accident, along with the tower controller. They claim that the tower had a football game on the television, and were distracted by this and not paying attention to the two planes. They also contend that the controller had limited knowledge of the capabilities of the 747, thus ordering them to make the 135 degree turns. The Dutch also contend that these turns could have been made by the Pan Am crew.

It's interesting to note how different the American/Spanish reports are from the Dutch report. The Dutch report comes across as trying to protect one of their most famous pilots, and keep him from being blamed for the deaths of amost 600 people. The Spanish report agrees with the American report in almost every aspect. The Dutch and Americans can be said to have an agenda as the NTSB wouldn't want to blame the US crew for screwing up, and the Dutch wouldn't want to blame the KLM crew for screwing up, but the Spanish were fairly neutral in the situation, as their only involvement was that the Canary Islands are their territory and it was a Spanish controller.

References:
www.answers.com...
www.airdisaster.com...
www.1001crash.com...
www.project-tenerife.com...

National Geographic's Seconds from disaster

they do a very good examination of the crash and point out all the links in the chain of events that lead to the fatal incident.





besides the information you have they also point out that one planes transmition was stepping on anothers and neither klm or pan am heard the information that each other needed.

the next time this episode is on:

Tuesday, April 11, 2006, at 5P

Seconds from Disaster
Collision on the Runway [TV-PG]
On Tenerife, a Pan Am flight taxied on the runway, while a KLM flight took off. But miscommunication caused one of the worst aviation disasters when the two jumbo jets collided, killing 583 people. Investigate what led to this fateful airplane collision.

Actually it was the Pan Am and the tower that stepped on each other. KLM announced they were taking off, and the tower tried to tell them to hold for clearance at the same time Pan Am said they were on the runway still.

From what you said there, I would blame vague communications from the control tower.

They should have asked if Pan Am was clear of the runway NOW, and not to report, same they should have told KLM to wait as Pan Am had not reported clear of the runway.

They DID try to tell KLM to wait, but Pan Am tried to say they were on the runway at the same time. The result was just a long squeal in the KLM cockpit. I believe it was at that point one of the other cockpit crew spoke up and asked if they were clear to take off, shortly after they began their takeoff roll.

If you listen to the communication between the tower and the KLM 747 it's just amazing how many times there is misunderstandings. The flight crew has no clue as to what is going on.


Five minutes before impact:

Time: Source: Content:
1701:57.0 RDO-2 Tenerife the Clipper one seven three six. (1702:00.2)
1702:01.8 APP Clipper one seven three six Tenerife.
1702:03.6 RDO-2 Ah- We were instructed to contact you and also to taxi down the runway, is that correct? (1702:07.4)
1702:08.4 APP Affirmative, taxi into the runway and -ah leave the runway third, third to your left, (background conversation in the tower).
1702:16.4 RDO-2 Third to the left, O.K. (17:02.18.3)
1702:18.4 CAM-3 Third he said.
CAM-? Three.
1702:20.6 APP -ird one to your left.
1702:21.9 CAM-1 I think he said first.
1702:26.4 CAM-2 I'll ask him again.

Three and a half minutes before impact:

1703:29.3 RDO-2 Would you confirm that you want the clipper one seven three six to turn left at the third intersection? (1703:35.4).
1703:35.1 CAM-1 One, two.
1703:36.4 APP The third one, sir, one; two, three, third, third one (1703:38.3)..
1703:38.3 CAM-? One two (four).
1703:39.0 CAM-1 Good.
1703:40.1 CAM-1 That's what we need right, the third one.
1703:42.9 CAM-3 Uno, dos, tres.
1703:44.0 CAM-1 Uno, dos, tres.
1703:44.9 CAM-3 Tres - uh - si.
1703:46.5 CAM-1 Right.
1703:47.6 CAM-3 We'll make it yet.
1703:47.6 APP ...er seven one three six report leaving the runway.
1703:49.1 CAM-2 Wing flaps?

At this point it's too late:

1705:44.8 KLM Uh, the KLM ... four eight zero five is now ready for take-off ... uh and we're waiting for our ATC clearance.
1705:53.4 APP KLM eight seven * zero five uh you are cleared to the Papa Beacon climb to and maintain flight level nine zero right turn after take-off proceed with heading zero four zero until intercepting the three two five radial from Las Palmas VOR. (1706:08.2)
1706:09.6 KLM Ah roger, sir, we're cleared to the Papa Beacon flight level nine zero, right turn out zero four zero until intercepting the three two five and we're now (at take-off). (1706:17.9)
ca. 1706:13 KLM-1 We gaan. (We're going)
1706:18.19 APP OK.
1706:19.3 RDO No .. eh.
1706:20.08 APP Stand by for take-off, I will call you.
1706:20.3 RDO And we're still taxiing down the runway, the clipper one seven three six.

dnausers.d-n-a.net...

I don't know how to post the actual recording, but if you listen to it they all seem to be having problems understanding each other.

It's a wonder that anyone got out alive.

If you read the Dutch acciident report that I linked to as a reference, they find that the KLM crew did nothing wrong. Capt van Zanten was very popular in the Netherlands at the time, and they come across as willing to do anything to protect his reputation.. They pin everything on Pan Am 1736 and the tower controller. The first take off attempt, that they stopped, the Dutch report claims was just runnng the engines up to check that they came up on power properly. They claim there was no confusion in the cockpit, and everything the KLM crew did had been done before on other flights, and other planes. They totally whitewashed their "investigation" to protect van Zanten.

I've worked with Dutch people before, and while I hate to generalise, out of a group of 6, only one of them were not arrogant and believed they were always in the right.

I wouldn't like to think they (the Dutch) are all like that, and we just got landed with mostly a bad bunch - but well...



Anyway, from what I've read, it seems all parties are to blame, probably more ATC as its there responsibility to clearly instruct the aircraft on what to do.

I can't open the PDF without it crashing my browser.

I can understand the Dutch pointing fingers at everyone else. KLM is their national carrier, and the pilot was a bit of a celebrity with the company.

I think the tower has some of the blame in this because they lost control of their airport, but the KLM crew made assumptions that led to the accident. The co-pilot seemed to know that they screwed up but never forces the point with the captain.

For such a small Island I find it amazing that about 884 people died in plane crashes from 1972 - 1980 on Tenerife. That's a pretty bad record.........

they showed this accident on air crash investigations. and they said if the klm hadnt taken on the extra fuel they would have cleared the pan am.
just thought id add my bit.