The exchange that followed between the Tower and the PanAm 747 was however audible on the KLM flightdeck. But by this time the KLM 747 was 20 seconds into its takeoff run. With Captain van Zanten and First Officer Meurs both concentrating fully on the takeoff itself, only Flight Engineer Schreuder took in the possible significance of the two transmissions. "Did he not clear the runway then?" he asked the pilots.

The captain, giving all his attention to the takeoff, did not take in the engineer's question either.

"What did you say?" he asked over his shoulder.

"Did he not clear the runway - that Pan American?" Schreuder repeated.

"Yes, he did," both pilots answered emphatically.

The KLM takeoff continued.

At this stage, the PanAm Boeing, its crew having missed the intersection for Taxiway 3 which the Tower had directed them to take, and unaware of what the other 747 was doing, was still on the runway, approaching Taxiway 4.

Captain Grubbs, still uneasy about occupying the runway in such poor visibility with the KLM aircraft's takeoff obviously imminent, was keen to be out of its way as soon as possible.

"Let's get the hell right out of here," he remarked to his crew:

"Yeah ... he's anxious, isn't he?" Bragg agreed.

"After he's held us up for all this time," enjoined Warns, "Now he's in a rush."

A few seconds later, the PanAm crew caught sight of lights that were materialising through the fog directly ahead. Hazy at first, they seemed for a long moment to be stationary. But as they continued to brighten, it quickly became obvious they were approaching fast!

Grubbs stared through the windscreen in stunned disbelief. "There he is ... look at him!" he cried out. "Goddamn ... that son-of-a-bitch is coming!" Desperately pushing all four throttles wide open, he attempted to swing the Boeing 747 off the runway to the left.

"Get off! Get off! Get off!" Bragg yelled frantically as he saw the other aircraft's nose begin to rise into the takeoff attitude.

Aboard the hurtling Dutch aircraft, First Officer Meurs' eyes were fixed on his steadily rising airspeed indicator. "V1!" he finally called.

At the same moment, van Zanten sighted the PanAm 747 slewing, across the runway ahead of them. Instinctively - there was no hope of stopping - he hauled back on the control column to try and lift over the American. But too suddenly - the tail bumper struck the runway, emitting a shower of metallic sparks.

But lift the KLM aircraft did - just before reaching the other - only it was too late. Its nose leg cleared the PanAm fuselage, but at 140 knots the main undercarriage slammed into it, slicing off the fuselage top as the No 4 engine demolished the hump just behind the flightdeck, and both aircraft exploded into flames.