In 1954 at 43 years old, Dr John Paul Strapp, a research officer at Edwards 
air force base, built a rocket-powered sled to investigate the effects of 
acceleration and decelaeration on the human body. He went from rest to 
632mph in 5s and decelerated thereafter with a force on his body of 40g. 
When he came round he was temporarily blinded owing to his eyeballs becoming 
fused to their lids.