CHICAGO (CBS) — The Aurora radar center that was damaged by an arson fire last week is on track to be restored and fully operational by Oct. 13, the head of the FAA said Friday, but he stopped short of promising long-term fixes in the immediate future.

FAA Administrator Michael Huerta toured the Chicago Air Route Traffic Control Center (ARTCC) with members of the Illinois congressional delegation, a week after a disgruntled contract employee allegedly set fire to equipment and cut cables there. The alleged actions of Brian Howard, 36, who is in federal custody, created a ripple effect that shut down Chicago’s airports, O’Hare and Midway.

“Everyone is working very, very hard,” Huerta told reporters at a news conference after the tour.

Accompanying the FAA chief were U.S. Sens. Dick Durbin and Mark Kirk.

Durbin said he was disturbed when he saw the damage in the radar facility’s basement.

“It is just stunning that this fire and smoke and soot that came from it, created such havoc,” he said.

Both he and Kirk have been critical of the FAA for last week’s standstill in air service, but they were cordial as they stood next to Huerta. Both said Congress needs to provide financial support to the FAA as it rebuilds its damaged infrastructure. But Kirk said it’s also essential the FAA establish a “hot, warm backup” system that ensures continuity of air traffic control in the event of another incident.

Huerta said the FAA would do its best in the short term but added a comprehensive overhaul is still a couple of years out.

Both airports still have not returned to full capacity. Huerta said O’Hare International Airport is operating at about 86 percent of its usual capacity, while Midway is at about 90 percent.

FAA crews have been working around the clock this week to repair and replace the damaged equipment. The FAA has said it expects have the Aurora facility up and running on Oct. 13.

Meantime, other air traffic control centers — including facilities in Cleveland, Indianapolis, and Minneapolis — have been trying to help pick up the slack, but both O’Hare and Midway have been operating at reduced capacity, with thousands of canceled flights in and out of Chicago over the past week.

The U.S. Travel Association has estimated the cost of flight cancellations and delays resulting from the radar facility fire to be $123 million and counting. Nearly 4,000 flights were canceled in the first four days after the fire.

“I want to sit down with the FAA Administrator, find out the root cause of these problems, and how quickly we can get this system up and running,” Durbin said.

Air traffic control problems were exacerbated Thursday by the threat of heavy storms, prompting airlines to cancel nearly 850 flights at O’Hare and Midway, even though heavy rain did not begin falling in Chicago until overnight.

According to the Chicago Department of Aviation, airlines at O’Hare had canceled nearly 230 flights on Friday, as of 10:30 a.m., while at Midway, there were only a few cancellations.

WBBM Newsradio’s Bernie Tafoya reports most other flights at O’Hare were supposed to be on time, but some were as much as two hours late. Midway also has some delays of up to 30 minutes.

Durbin said he’s frustrated with the pace of repairs to the ARTCC and the subsequent effect on flights at O’Hare and Midway.

“I’m very impatient. When the head of United Airlines tells me that flights are going to be down 40 percent today, Thursday, I’m disappointed. I thought we’d be in much better shape than we are today,” Durbin said.

Huerta has said the FAA is reviewing security measures at all its facilities, and working on a contingency plan.

Durbin seemed incredulous that there were no backup systems in place when the ARTCC in Aurora was damaged, and apparently no recovery plans that would allow O’Hare and Midway to quickly get back to full capacity.

Federal prosecutors have charged Howard, 36, with destruction of aircraft facilities. He is being held without bond.