Post On 2019-10-28

How Feynman found out the cause of the Challenger crash

In 1986, the space shuttle Challenger exploded just after its launch. President Reagan ordered a special commission of inquiry to be organized. Feynman is one of them. When Feynman went to investigate, a group of experts brought him a thick report material and prepared to report to him step by step. Feynman said, wait, let me ask you a question. So he started with the first paragraph on the first page, asking questions one by one. This attitude of not playing cards according to the rules made the head of the investigation committee and other members unhappy, but Feynman insisted on his own independent investigation. In the end, he found a seemingly impossible cause: what led to this tragedy was a small rubber O-ring on the rocket booster.

At a public meeting, Feynman did a simple experiment. He took a glass of ice water, then kneaded the O-ring and put it into ice water. Then he took it out of ice water. The O-ring did not return to its original shape. How could Feynman think of an O-ring problem? In fact, a NASA astronaut once raised the issue of sealing ring, and another friend of the same member of the investigation committee called Feynman: "when I repair the fuel injector in the morning, I suddenly thought, is it the low temperature that affects the performance of the sealing ring?" That inspired Feynman to find out. On the day of the launch of challenger, the weather at Kennedy Space Center was extremely cold, which was the direct cause of the failure of O-ring.