Instructions to Turn Off the Active Runway

Because of a sudden fog shrouding the active runway (which was also used as the active taxiway), the Pan Am crew could not see the third exit (referred to as "Charlie 3") which tower officials told them to use before, and during, KLM's take-off.

Adding to the confusion was the shape of the designated exit. Charlie 3 made a very sharp turn, pointing a soon-to-takeoff plane in the wrong direction.

To clarify the situation, First Officer Bragg asked the tower a series of questions:

ROBERT BRAGG: Would you confirm that you want Pan Am 1736 to turn left at the third intersection?

FERNANDO AZCUNAGA [Tenerife tower personnel]: The third one, sir: one, two, three. Third, third one.

ROBERT BRAGG: One, two.

VICTOR GRUBBS [Pan Am's pilot-in-command]: Good. That's what we need right, the third one?

GEORGE WARNS [the Pan Am Flight Engineer]: Uno, dos, tres.

VICTOR GRUBBS: Right.

However, as Robert Bragg says in the Nova documentary, The Deadliest Plane Crash: "We saw the fog bank come off of the right hill, and proceed down and stop right on the runway. So our visibility went from unlimited to 500 meters. We lost sight of the KLM airplane...We couldn't see any taxiways. We couldn't see...barely, the centerline of the runway we were taxiing on..."