The Federal Aviation Administration (FAA) is aiming to repair an air traffic control center damaged by an employee-set fire and return it to full service by October 13, CNN reports.
The FAA is brining in extra technicians to aid in the repair of the facility. Repairs have been delayed as air traffic controllers have had to manually transfer flight data that would normally be transferred via computer.
More than 550 flights had been cancelled at Chicago O'Hare and more than 50 had been canceled at Midway Airport as of midday Sunday.
On Saturday, more than 670 flights were canceled at O'Hare and 125 at Midway, the Chicago Tribune reports.
The fire, which police have said was set by a contract employee, grounded flights across the country beginning Friday.
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