liquid oxygen in the upper-stage tank had begun sloshing around several minutes after launch, inducing a fatal oscillation. The problem they had known about, discussed in detail, and ultimately dismissed as the eleventh highest avionics risk took down their rocket. “Now,” Musk says, “I ask for the eleven top risks. Always go to eleven.” It’s true. The company now does lists of the top eleven risks ahead of launches. That is one legacy of the second failure of the Falcon 1 rocket.
