There are plenty of stories going around from this past weekend about the astounding number of flights canceled due to computer and staffing problems. While US Air got plenty of headlines for their staffing issues (baggage handlers calling in sick at record rates leading to planes that were simply filled with excess lost baggage), the more interesting story appears to be Delta's subsidiary Comair. Lots of articles are talking about the 1,100 flights on Christmas day due to their computer system getting knocked out, but there's very little info on the actual cause of the problem. There's just the fact that no one can explain why there was no backup system, and that the computer crash was caused by the system being overwhelmed after weather problems required many flights to be canceled and crew to be reassigned. In other words, a lot of users were trying to figure out how to reassign flight crews to different flights, and all that activity made the system lie down and go to sleep. You would think that anyone building systems this important would have backups in place and build things in a way that would make them unlikely to crash, but this is hardly the first time things of this nature have happened.