About Roger Boisjoly
Roger Mark Boisjoly was an American mechanical engineer, fluid dynamicist, and an aerodynamicist. He is best known for having raised strenuous objections to the launch of the Space Shuttle Challenger months before the loss of the spacecraft and its crew in January 1986. Boisjoly correctly predicted, based on earlier flight data, that the O-rings on the rocket boosters would fail if the shuttle launched in cold weather. Morton Thiokol's managers decided to launch the shuttle despite his warnings, leading to the catastrophic failure. He was considered a high-profile whistleblower. During his investigation, he discovered that the first of a system of two O-rings had failed completely and that damage had been caused to the second O-ring. The temperature at launch had been only 10 °C (50 °F), the coldest on record (until January 28, 1986).
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