John Paul Stapp's famous rocket sled stops

This video shows John Paul Stapp riding rocket sleds (and other test vehicles) to discover the limits of human endurance. The endurance part came at the end of each ride—when the vehicle made a sudden stop.  Stapp was interested in learning how to build aircraft that would better allow people to survive a crash. The project led to the naming of Murphy's Law, for which many years later Stapp, Captain Edward A. Murphy, Jr., and George Nichols were awarded an Ig Nobel Prize in Engineering.

For details of the project and the man, see "The Fastest Man on Earth," Nick T. Spark, Annals of Improbable Research, vol. 9, no. 5, Sept/Oct 2003. Nick Spark later  enhanced and adapted the article into the book A History of Murphy's Law.

Here's more footage of John Paul Stapp.