Questions emerge after fire at FAA facility in Aurora grounds Chicago flights

AURORA, Ill. (WLS) -- As the Federal Aviation Administration gets air traffic moving again in and out of Chicago after a fire at the Air Route Control Center in Aurora, there has been a call for answers as to how it could happen.

A new written statement from the FAA late this evening says that O'Hare Saturday was able to handle 60 percent of its flights, 75 percent at Midway, and that it expects a substantial increase in flight operations by Monday.

The damage from the sabotage at its Aurora facility is so severe, the FAA has decided to completely replace its central communications network in a different part of the building, and technicians will be working round the clock on that.

DOCUMENT: Complete FAA statement

The sabotage was like nuking the Central Nervous system of the center. Everything disappeared from radar. There was way to communicate with planes or other facilities. And it's not like anyone can flip a switch to a full-scale back-up system. With computer connections out, the airlines have to fax their flight plans to the O'Hare tower, for example. Handling everything manually means two controllers per position.

Other centers and towers are taking over as much traffic as possible. And arrival and departure rates have improved. A controller's union spokesman says O'Hare Saturday handled 60 percent of its normal volume.

But the key question is how long repairs will take. The FAA has not yet given an estimate.

PHOTOS: Fire at regional FAA facility grounds Chicago flights

"We need to know sooner when they expect to have things back to normal, and if they don't know they should tell people right away," said Congressman Mike Quigley (D-Chicago).

The FAA has been roundly criticized for not moving faster to explain and inform.

"Now that we've had a full interruption, we've had a full cardiac arrest here in the aviation system, we've got to have a way to bounce back more quickly," said Senator Mark Kirk (R-Illinois).

Kirk says he wants the FAA to fully review the vulnerabilities of the air traffic control system while answering the question "how could one guy with a grudge cause such chaos?"

"This is the beating heart of the U-S economy. It needs to run 24-7, no matter what," he said.

"We need to know what happened and why," Quigley said. "How we can prevent it in the future, and how to make sure when this sort of thing happens that we fall back to another system that allows the system as a whole to go forward."

The man charged with causing the chaos remains hospitalized. Investigators have been talking to Brian Howard's co-workers and family to try to better understand motive.

Airlines are urging travelers to check the status of their flights at www.fly.faa.gov.