An air traffic control system in Los Angeles failed, losing contact with 400 airplanes. The main system failed and the backup system did not take over as expected. The failure was due to a software timing issue - the system had a countdown timer that would reset too high, causing the system to shut down after 50 days without being restarted. This known issue was an oversight by the manufacturer and exposed system to failure by not addressing the problem as instructed. The failure highlights the risks of technical deficiencies and lack of client participation in complex software projects.

1. Software Failure: Air Traffic Control System Presented by: S.A Arain & A.R Shaikh Dated: 10-11-2009 Mehran University Institute of Science and Technology Development