“In a nutshell, Columbia experienced two failed computers, one of which we restored only to have it fail again at landing. The cause of one of the failures turned out to be a sliver of solder eleven-thousandths of an inch thick that became dislodged when the thrusters were fired, shorting out the CPU board. During the postflight debriefing, I remarked about this incident, “Had we activated the backup flight software when the problem first emerged, loss of vehicle and crew would have resulted.”