December 10, 1954
Flight surgeon and U.S. Air Force Colonel John Paul Stapp earned the nickname of “Fastest Man on Earth” when he rode a rocket-powered sled up to 632 miles (1,017 kilometers) per hour in five seconds. The 44-year-old Stapp rode that sled, which was called the Sonic Wind, at Holloman Air Force Base in New Mexico.
In riding the sled as it covered a total of 3,500 feet (1,077 meters), Stapp set world records for both the fastest manned rail vehicle and the fastest open-cockpit vehicle. The main purpose of this experiment, however, was to assess if a pilot could eject from an airplane at supersonic speed and survive while doing so. At the end of the ride, the sled was stopped in 1.4 seconds. This quick stop subjected Stapp to a force equivalent of 40 Gs (“G” referring to a force on the body as the result of gravity) – more than any human yet endured voluntarily and the equivalent of slamming into a brick wall in an automobile traveling at 120 miles (193 kilometers) per hour.
While managing a half-smile as he was pulled out of the sled, Stapp was in great pain and his eyes flooded with blood due to the bursting of most of their capillaries. (He would quickly regain much of his vision, although his eyesight would never quite be the same again.)
Stapp became an international celebrity, appearing on various television programs (including the popular series This is Your Life!) and magazine covers. Stapp’s history-making rocket sled ride and similar efforts that followed were invaluable to the design of such aviation safety features as improved helmets, better aircraft seats, and stronger harnesses. Stapp, for his part, became strongly interested in the implications of those experiments for automobile safety and would serve as a staunch champion for that cause.
For more information on John Paul Stapp, please check out https://en.wikipedia.org/wiki/John_Stapp