FAA Software Problem

An FAA software failure caused delayed departures in the US in June 2007. Computerworld first reported on June 12, that "investigators still don't know what caused a computer system problem on Friday that shut down one of two systems used by the Federal Aviation Administration to distribute aircraft flight plans filed by pilots across the U.S."

United Airlines

[21 June 2007] The United Airlines computer system responsible for dispatching flights for departure went down, forcing the airline to temporarily ground all flights for about two hours. Ciose to 300 flights were delayed or canceled. But the day after the glitch, United's system, called Unimatic, was not blamed for the error. COO Peter McDonald said the error, which took place during routine testing, was caused by employee error. The error affected both the primary system and the backup. Apparently the employee accidentally disabled both systems during a test run.

According to a report by Baseline, "Michael Boyd, an airline consultant based in Evergreen, Colo., told the Chicago Tribune that United's computer glitch will cost it more than $10 million in lost revenue due to refunds and re-bookings."

No additional details were given.

Predator UAV Failure

An April 2006 crash of a Predator UAV near Nogales was indirectly caused by repeated software failures. As reported by USA Today:

No one was injured, but the plane slammed into a hillside near homes in a sparsely populated area north of Nogales, Ariz. A 'pilot' flying the single-engine turboprop plane from a trailer at a military base accidentally shut down the plane's engine while attempting to deal with a locked up computer control console, according to the NTSB.

The NTSB found several disturbing problems in their report:

• Computers used to control the Predator had locked up at least 16 times in the four months before the accident. The failures were not well documented and no attempt was made to determine what caused the problems.
• The drone's pilot was supposed to be monitored by a flight instructor, but none were around at the time of the outage.
• When the Predator's engine stopped, it cut electrical power to key instruments, including the radio transponder that made the plane visible to air-traffic controllers. This meant that nobody knew where the plane went, including other aircraft.
• The Predator's engine cannot be restarted without a radio link to the ground. By the time the operators realized the drone had lost power, it had descended behind mountains and radio contact was impossible.
• A report in C4ISR Journal mentions that the operator had attempted to transfer control to a secondary workstation. However, this procedure calls for the secondary workstation to be "identically configured" at the time of the transfer. The secondary workstation was configured in "fuel off" mode, so the drone obeyed this command.

The Predator B destroyed in the crash cost $6.5M.