January 5th, 1972

On this page are the FBI Report and photos regarding the “Sled Test”, which proved Northwest Airlines’ theory that the pressure bump felt by the crew was Cooper jumping from the aircraft. The effort was a joint venture by the FBI, Northwest Airlines, and the U.S. Air Force.

Flight Engineer Harold Anderson occupies the same seat he did on the night of the hijacking. The pilot is Paul Soderlind, co-pilot is Eric Linden, and in the jumpseat is Captain Thomas Spangler.

An Air Force C-141 trails alongside the 727, preparing to record video of the Sled Test.

Cooper’s seat, 18-E, is visible on the left side of the image.

Sgt’s David Saiz and Wallace Johnson prepare a weighted sled.

Captain Ronald Wilson stands at the bottom of the stairs. His goal was to determine how far the stairs would lower from a man’s body weight. He reported that Cooper would have been able to stand at full height while at the bottom.

Sgt. David Saiz lowering a sled into position.

Sgt. Saiz prepares to release the sled.

Sgt. Saiz releases the sled.

Still shots from the video recorded by the Air Force C-141 shows the rebound effect as the sled is released.

The sled has just dropped and the stairs are still rebounding as Sgt. Saiz returns to the cabin.

Note the torn aft stair skirting above Agent Milnes’ head. Very similar damage was taken by the aft stairs on the night of the hijacking.