The B-58 Hustler was the world's first supersonic jet bomber, a delta-winged marvel of Cold War design created in the 1950s solely to deliver nuclear weapons to the U.S.S.R. And the "pilot" used to test the capsule ejection system was a live bear. The plane was fraught with problems – it was difficult to control and expensive to maintain. Designers also learned that emergency ejections above Mach 2 were deadly. After losing an entire crew, they began work on a new ejection system that would protect the occupants even in extreme circumstances.
Researchers started out testing the system on the ground, with acceleration sleds. The first subjects were people recruited from the unemployment lines, but the ground tests moved on to chimps and bears. Yes, bears. It seems that Himalayan and American black bears were readily available and approximated the mass and body shape of a human.
When testing moved to the sky, the bears went too. Living bears were sedated, then strapped into the capsules. The capsules were ejected from planes at various speeds and altitudes to determine how well the system worked. The bears were later examined to see if they were injured. None of the bears were killed in the tests, though they did suffer some broken bones, muscle damage and internal injuries."
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