Rocket sled

Sliding pads, called "slippers", are curved around the head of the rails to prevent the sled from flying off the track.

[3] Rocket sleds were used extensively early in the Cold War to accelerate equipment considered too experimental (hazardous) for testing directly in piloted aircraft.

The sled was then accelerated according to the experiment's design requirements for data collection along a length of isolated, precisely level and straight test track.

Testing ejection seat systems and technology prior to their use in experimental or operational aircraft was a common application of the rocket sled at Holloman Air Force Base.

Perhaps the most famous, the tracks at Edwards Air Force Base were used to test missiles, supersonic ejection seats, aircraft shapes and the effects of acceleration and deceleration on humans.