If you had a terrible time trying to fly somewhere in the U.S. this past weekend, you’re not alone: hundreds of flights were delayed or canceled along the East Coast on Saturday before travel returned to a more normal pace on Sunday. The Federal Aviation Administration says the technical problem at a Virginia air traffic control center that caused the travel issues could be linked to a software upgrade at the facility.

On Sunday the agency said the travel nightmare was likely connected to a software upgrade at one of its Leesburg, VA traffic control centers. The FAA has disabled the features that were included in the upgrade, the Wall Street Journal reports, calling the disruption an “automation failure.”

The difficulties on Saturday prompted the FAA to restrict flights in the area served by that center from 11 a.m. to 4 p.m. Saturday. All told, the FAA says there were about 492 delays and 476 cancellations related to the technical problems. That amounts to about 70% of normal Saturday air traffic at the Baltimore-Washington International Airport, 72% at Ronald Reagan Washington National Airport and 88% at Dulles International Airport, notes the Associated Press.

The big airlines said on Sunday that most or all of their passengers had been rebooked on new flights. American Airlines was hit particularly hard, with 245 cancellations. United Airlines had 70.

FAA Software Upgrade Fails, Triggering Travel Nightmare [Wall Street Journal]

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