An anonymous reader writes: On January 27, 1967, the Apollo 1 crew was performing a "plugs-out" test of the Command/Service Module, an essential simulation of how the three-person capsule would perform under in-space conditions under its own power. At 6:30 PM, a voltage spike occurred, leading to a disaster. In 26 seconds, everything changed. The Apollo 1 fire and the tragic death of all three astronauts wasn't due to just a single point-of-failure, but rather due to five independent confounding factors that if any one of them had been different, the astronauts Grissom, White and Chaffee might have survived. As it stands, all the crewed Apollo missions were scrapped for 20 months while NASA changed how they did business. The changes worked remarkably well, and 2.5 years later, humans walked on the Moon.