According to TechWorld (http://www.techworld.com/), recent outages at LAX are due to poor integration of an "upgrade" from Unix to Windows: http://www.techworld.com/opsys/news/index.cfm?NewsID=2275
They report that "The servers are timed to shut down after 49.7 days of use in order to prevent a data overload, a union official told the LA Times. To avoid this automatic shutdown, technicians are required to restart the system manually every 30 days. An improperly trained employee failed to reset the system, leading it to shut down without warning...".
I dunno about the rest of you, but I can schedule a Windows server to reboot once a week if it's running software suspected of not releasing resources when it should. Wonder why they can't?
Wasn't it Microsoft itself that said that Windows should NOT be use for "Mission Critical Applications"?