The Deadliest Plane Crash

The Tenerife Airport Disaster occurred at just before 5:07pm on 27 March 1977. Despite the terrible loss of life as a result of the terrorist attacks on the Twin Towers in 2001, the tragic accident at Los Rodeos still retains the dubious title of having the highest number of fatalities (excluding those on the ground) of any single incident in aviation history.

The circumstances resulting in the Tenerife Airport disaster came about due to an unfortunate series of unrelated events.

There were two aircraft involved in this Tenerife Airport disaster, a Pan American World Airways and a KLM Royal Dutch Airlines, both of them Boeing 747s. In 1977, Los Rodeos Airport only had one runway and the two aircraft found themselves taxiing along it in opposite directions, on a collision course.


Both aeroplanes were bound for Las Palmas, on the island of Gran Canaria. It was only as they were approaching the Canary Islands that events began that would ultimately lead to the tragedy.
At 1:15pm on the day of the accident, a small terrorist bomb exploded in the terminal building of Las Palmas Airport. There had been a warning, so there were a few injuries, but no deaths. A phone call claimed resposibility and told of a second bomb. The airport authorities had no choice but to temporarily close the airport.
The Pan Am and the KLM aircraft were both told to divert to the nearest alternative airport, which was Los Rodeos. At least three other large, long-haul planes were directed there too.
Los Rodeos Airport was ill-equipped to deal with so many large aircraft. As mentioned earlier, it had only one runway, plus one main taxiway, running parallel to it. There were also several smaller taxiways connected to this main one. With so many large planes to accommodate, it was necessary to park them on the main taxiway, resulting in planes about to take off having to taxi into position using the actual runway.
Whilst on the ground, the captain of the KLM flight decided to refuel, to save time. This decision meant that the aircraft was fully fuelled when the Tenerife Airport disaster occurred - and the resulting conflagration was that much more terrible.

Simplified map of runway, taxiways, and aircraft. The red star indicates the location of impact.

Eventually, word came through that Las Palmas Airport had been reopened, so the KLM plane was cleared by the control tower and told to backtaxi to the end of the single runway, then make a 180 turn (a difficult manoeuver in such a narrow space). The aircraft's crew were asked to acknowledge this clearence, but, because they were performing their pre-flight check, this was never made until the plane was in take-off position. Meanwhile, low clouds had drifted in, resulting in a fog that limited visibility to just under 1000 feet.


Next, the Pan Am flight was instructed to backtaxi along the same runway, then leave it at the third exit, taking it onto the main taxiway. The captain asked for a repeat of the exit number and was told "The third one, sir, one, two, three, third. The third one". The aircraft began its slow taxi, with the crew using a map of the airport to find the required exit. Remember, it was foggy by this time. It appears that the crew never managed to identify the correct exit 3. This is reflected in the fact that the imminent collision eventually happened near the fourth exit.
It was at about this time that there appear to have been misunderstandings in communication between the planes and the control tower. The captain of the KLM flight instructed his co-pilot to report that they were ready for take-off and to request clearance. The control tower then gave a clearance which specified the aircraft’s departure route and gave instructions of what to do after take-off. It was not a specific clearance for actual take-off.
The co-pilot's reply was "We're now at take-off", to which the control tower replied "OK". It appears that the flight crew meant that they were actually beginning their take-off, while the controller took it to mean they were in take-off position, awaiting final clearance. He added, "Stand by for take-off, I will call you".
At that point in events leading to the Tenerife Airport disaster, there occurred the most unfortunate coincidence of all. A simultaneous radio call from the Pan Am flight, saying that they had not finished taxiing and were still on the runway, had the effect of causing radio interference, so the control tower's last few words were not heard by the KLM captain. The crucial information of the Pan Am flight's position was also lost. If both these messages had been heard, the KLM flight would have been able to abort its take-off.
Because of the fog, the aircraft could not see each other and neither could be viewed from the control tower. Also, Los Rodeos Airport wasn't equipped with ground radar. The tower asked the Pan Am flight to report when it was clear of the runway. Its captain replied, "OK, we'll report when we're clear". On hearing this, the flight engineer on the KLM flight expressed concern about the position of the other aircaft. The KLM captain, however, seemed positive he had been given clearance for take-off and continued down the runway.
As the two planes approached one another, their respective crews eventually saw the other plane's landing lights through the fog. The Pan Am captain applied full power and attempted to veer sharply onto the fourth exit. The KLM captain attempted a steep climb, scraping the planes's tail along the runway for some 65 feet. It left the ground, but its underside struck the Pam Am plane's upper fuselage, ripping it apart. The KLM plane stalled and came down some 500 feet further on, then slid a further 1000 feet.
The loss of life from the Tenerife Airport disaster was horrendous. From the KLM flight, all 234 passengers and 14 crew perished. 326 passengers and 9 crew on the Pan Am flight died, primarily due to the spilt fuel igniting and exploding. 56 passengers and 5 crew from this flight survived. Some people who had survived the crash and were out on the runway were killed by shrapnel flying from the 747's engines, which were still running after the impact. Firefighters initially rushed to the KLM aircraft, believing, due to the thick fog, that there was only one plane involved. Ironically, this was the plane with no survivors.

Dutch response

The Dutch authorities were reluctant to accept the Spanish report blaming the KLM captain for the accident. The Netherlands Department of Civil Aviation published a response that, whilst accepting that the KLM aircraft had taken off "prematurely", argued that he alone should not be blamed for the "mutual misunderstanding" that occurred between the controller and the KLM crew, and that limitations of using radio as a means of communication should have been given greater consideration.
In particular, the Dutch response pointed out that

• the crowded airport had placed additional pressure on all parties, KLM, Pan Am, and the controller;
• sounds on the CVR suggested that during the incident the Spanish control tower crew had been listening to a soccer game on the radio and may have been distracted.
• the transmission from the tower in which the controller passed KLM their ATC clearance was ambiguous and could have been interpreted as also giving take-off clearance. In support of this part of their response, the Dutch investigators pointed out that Pan Am's messages "No! Eh?" and "We are still taxiing down the runway, the Clipper 1736!" indicated that Captain Grubbs and First Officer Bragg had recognised the ambiguity;
• if the Pan Am aircraft had not taxied beyond the third exit, the collision would not have occurred.

Speculations

Speculation regarding other contributing factors includes:

• Captain Van Zanten's failure to confirm instructions from the tower. The flight was one of his first after spending six months training new pilots on a flight simulator, where he had been in charge of everything (including simulated ATC), and having been away from the real world of flying for extended periods.
• The flight engineer's apparent hesitation to challenge Van Zanten further, possibly because Captain Van Zanten was not only senior in rank, but also one of the most able and experienced pilots working for the airline.
  • A study group put together by the Air Line Pilots Association found that not only the captain, but the first officer as well dismissed the flight engineer's question. In that case, the flight engineer might have been either reassured or even less inclined to press the question further.
• The reason only the flight engineer reacted to the radio transmission "Alpha one seven three six report when runway clear" might lie in the fact that this was the first and only time the Pan Am was referred to by that name. Before that, the plane was called "Clipper one seven three six". The flight engineer, having completed his pre-flight checks, might have recognized the numbers but his colleagues, preparing themselves for take-off, might have subconsciously been tuned in to "Clipper".
• The extra fuel the KLM plane took on added several factors:
  • it delayed takeoff an extra 35 minutes, which gave time for the fog to settle in;
  • it added over forty tons of weight to the plane, which made it more difficult to clear the Pan Am when taking off;
  • it increased the size of the fire from the crash that ultimately killed everyone on board.
• Captain Van Zanten's reaction, once he spotted the Pan Am plane, was to attempt to take off. Although the plane had exceeded its V1 speed, it did not yet have adequate airspeed. The sharp lifting angle caused the KLM jet to drag its tail on the runway, thereby reducing its speed even further.

Responsibility

Although the Dutch authorities were initially reluctant to blame Captain Van Zanten and his crew,^[
  the airline ultimately accepted responsibility for the accident. KLM paid the victims or their families compensation ranging between $58,000 and $600,000^. As reported in a March 25, 1980, Washington Post article the sum of settlements for property and damages was $110 million (an average of $189,000 per victim, due to limitations imposed by European Compensation Conventions in effect at the time).

A monument dedicated to the memory of all the people who lost their lives on that fateful day was eventually erected.

Memorials

A Dutch national memorial and final resting place for the victims of the KLM plane is located in Amsterdam, at Westgaarde cemetery. There is also a memorial at the Westminster Memorial Park and Mortuary in Westminster, California.  

The 30th anniversary marked the first time that Dutch and American next of kin, and aid helpers from Tenerife, joined in international commemoration service held at the Auditorio de Tenerife in Santa Cruz; the International Tenerife Memorial March 27, 1977 was inaugurated at the Mesa Mota March 27, 2007. The monument was designed by Dutch sculptor Rudi van de Wint. A special 50-page commemorative booklet including a DVD in English, Dutch, and Spanish was published a year later, on March 27, 2008.

Notable victims

Eve Meyer

• Eve Meyer, a pin-up model, film actress and producer and former wife of Russ Meyer.
  
  
• A. P. Hamann, the former city manager of San Jose, California, and his wife Frances Hamann.
  
  
  

Documentaries

The disaster has featured in many TV shows and documentaries. These include Crash of the Century, the Survival in the Sky episode Blaming the Pilot, the Seconds From Disaster episode Collision on the Runway, PBS's NOVA episode "The Deadliest Plane Crash" in 2006, and the Discovery Channel TV series Most Deadly and Destroyed In Seconds..


Source:
1. http://en.wikipedia.org/wiki/Tenerife_airport_disaster
2. http://www.tenerife-information-centre.com/tenerife-airport-disaster.html
3. http://dsc.discovery.com/videos.html