Posts Tagged ‘Tenerife’


The disaster that saved lives

March 27, 2009

Captain Jacob van Zanten was the epitome of an airline pilot.  He dressed sharply; his experience and respect positioned him as an instructor for pilots new to the Boeing 747, while his charm and good looks made him a natural choice to be featured in much of his company’s PR material and to be its de facto spokesperson.  In both the public’s eye and in the cockpit he was viewed as a God.

And that is precisely what caused the single worst aviation disaster in history.

On March 27th, 1977 Captain van Zanten crashed his KLM Airlines 747 into a Pan Am 747 on takeoff, killing 583 passengers and crew.  Though bad weather, bad judgment and even an act of terrorism contributed to the two jumbo jets being on a collision course that Sunday evening, the disaster’s ultimate cause lay in the way an airline captain’s authority was considered unquestionable and inerrant.

His was not simply the last word, it was the only word.

As airlines grew, so did their need for pilots.  Following World War II, there were thousands of trained young men ready to fill those positions created by the growing economy and its demand for fast travel around the country and the world.  It was only natural then, when the military’s culture of discipline and absolute adherence to the chain of command became the accepted norm.

While the unique demands of combat may require a strict, unquestioning reliance on such a system, it proved not to be the best fit for safe public transportation.  In war, there are times when a mission must be undertaken to ultimately save a few or even many thousands of lives.  In commercial aviation however, safety must be the primary consideration.  Flying people on vacation to Disneyworld or business travelers to Cincinnati is not obligatory.  There’s a saying that sums it up nicely:

Takeoffs are optional.  Landings aren’t.

But this lesson hadn’t been learned yet.  Captain van Zanten ultimately ignored the objections of his crew at Tenerife.  There was confusion over whether or not the tower had said they could take off yet.  The men working there had been using non-standard phrases and spoke poor English – the international standard for all aviation communication.

The small airport was pushed to the limit.  They simply were not equipped to handle the dozen or so large aircraft (carrying hundreds of passengers each) that were on the ground.  The planes were diverted to Tenerife after one bomb exploded and threats of another closed their destination, Las Palmas.  All day long, the jumbo jets sat on the ground, waiting at a facility that was neither equipped to handle them, nor their hundreds of passengers.

Once Las Palmas re-opened, fog and lack of space for taxing and takeoff meant there was a lot of radio chatter as controllers tried to get the delayed planes back into the air.  Since the airport wasn’t designed to handle so many large aircraft at the same time, it required more than one to be on the runway at the same time.

When the KLM flight reached the approach end of runway 30 (pronounced “three zero”) it turned around and waited for word from the tower that it could take off.

At this point the Pan Am 747 was still taxiing on the runway towards the other plane.

In the KLM cockpit, Captain van Zanten was watching the clock.  His crew was approaching the end of their legally mandated duty times and would not be able to continue past them.  He knew that if the flight did not leave soon, it would not leave at all.

Then controllers radioed an instruction for Pan Am to make a turn off the runway that didn’t make sense.  It would bring them back to the terminal instead of towards the end of the runway.  Several calls were made back and forth between the cockpit and the tower to clarify what exactly, the Pan Am crew were supposed to do.  The were told to take the next exit off of the runway.

Confusion ensued.

Hearing that the other 747 was supposed to clear the runway, but without an explicit clearance to take off, Captain van Zanten announced to his crew that he was taking off.  The First Officer (FO) spoke up, saying that they had not been cleared yet.  The obviously miffed and possibly embarrased van Zanten grudgingly brought the four hundred ton plane to a stop.

Communication between the tower and the Pan Am jet continued, as its crew tried to understand what the controllers wanted them to do.

Now Van Zanten had his FO query the tower for their take off clearance.  The tower repeated the aircraft’s instructions on what to do after departure, but didn’t issue a take off clearnce.   Inexplicably, the veteran pilot with over eleven thousand hours flight experience advanced the four thrust levers on the 747 and doomed the lives of almost six hundred people.  This time the FO said nothing.

In the Pan Am cockpit, the crew was unaware that KLM was accelerating towards them.  They were still trying to make sense of what the tower had told them.

There was however, still a chance to avoid the disaster.  The Flight Engineer (FE) had been listening to the radio and asked aloud if the other plane was clear of the runway.  Both van Zanten and the FO (now following the lead of his superior) responded “He’s clear”.  The FE stopped his objection.  He had no reason to question the two senior crew members.

The final moments of the flight are well described in this article:

The last recorded words from the crew of KLM was a familiar epithet to those who regularly hear cockpit voice recorder tapes. More than one pilot had uttered the same phrase when confronted with the possibly irreversible reality of impending disaster.  Captain van Zanten said simply:

“Oh, shit!”

The planes crashed.  Hundreds of people perished.

Though it would be easy to blame both crewmen in the cockpit for failing to continue their objections, it simply was not possible for them to do so.  It was not part of the culture.

This fact did not go unnoticed by the industry.  Reliance upon one person to make critical decisions has been replaced by a collaborative effort called Crew Resource Management or CRM.  A system where all members of the crew are utilized in decision making is now the standard for multi-pilot aircraft.  From day one, commercial pilots are taught the advantage of utilizing all of the resources available to them, to include fellow pilots, crewmembers, air traffic controller and even passengers.  While the captain does have the final decision in many, but not all matters, pre-employment screening weeds out those who are unable to work as a team.  Both initial training and continuing education emphasize reliance upon and the cultivation of a cooperative environment in the cockpit and cabin.

Alongside continued technological advances these changes in the way a Captain interacts with fellow pilots have proven successful.  Airlines have seen tremendous growth in safety due to reduction of not only human error, but in the ability of a crew to respond to rare, but inevitable mechanical failures.  The outcomes of the accidents at Sioux Falls and the Hudson river would not have been possible if it were not for their Captains’ involvement of the entire crew in dealing with the emergency.

In no small way, those lives that were lost on Tenerife thirty two years ago have directly led to the safe air travel we enjoy today.  To learn from their tragedy is to honor them.

List of passengers on Pan Am 1736

List of passengers on KLM 4805