FAA officials said a computer glitch forced aviation employees to enter pre-flight plan information into computers by hand.
Joe Lewnard | Staff Photographer
Airline passengers in Chicago Thursday felt the reverberations of a computer glitch that delayed and canceled flights at airports in the Midwest, South and East.
Flights from O'Hare International and Midway Airports were delayed or canceled throughout the day, after a route problem disrupted a number of air traffic management services and flight plan processing at about 5 a.m., said Elizabeth Cory, a spokeswoman for the Federal Aviation Administration.
The failure, tracked to Salt Lake City, prompted the FAA services to do traffic flow and flight planning manually for a period of time.
At O'Hare, midafternoon delays were running at about 20 minutes with some cancellations. At Midway, delays were about 30 minutes, though 90-minute delays were reported for some flights to the east coast.
The problem was resolved at approximately 9 a.m. eastern time, but it took longer for the airlines to catch up and eliminate the delays.
Air traffic control radar and communication with aircraft were not affected and critical safety systems remained up and running throughout the incident, Cory said. She added there was no indication the outage occurred as a result of a cyber attack.
FAA spokesman Paul Takemoto said airplane dispatchers had to send plans to controllers, who entered them into computers by hand. "It's slowing everything down," Takemoto said.
The hardest hit area was Hartsfield-Jackson Atlanta International Airport, the world's busiest airport where AirTran had canceled 22 flights with dozens more delayed. Delta Airlines also has been affected.
Only minor delays were reported at metropolitan New York City area airports, according to the Port Authority of New York and New Jersey.
Associated Press contributed to this report.