Near normal at MSP after weekend Chicago fire scrambled flights

Updated 1:50 p.m.

Air traffic is slowly returning to normal at Minneapolis-St. Paul International Airport following last week's fire at a Chicago-area air traffic control center.

The Federal Aviation Administration has moved air traffic controllers to other control centers, including one in Minnesota, to compensate for the loss of the tower. The agency expects operations to return to normal across the country by Oct. 13 and on Monday ordered a full review of its contingency and security plans because of the fire.

• Related: Air controllers pick up slack after Chicago fire

The fire was allegedly set Friday by a contractor working at the control center. It forced the temporary closure of the O'Hare and Midway airports in Chicago and cancellations of thousands of flights around the country.

Despite the inconvenience, air traffic experts say the system worked well to make sure passengers already in the air arrived safely. They say the system would function the same way if a similar event knocked out air traffic controls here.

The system is built to anticipate potential failures like the fire at the control center, added John Hansman, director of the Massachusetts Institute of Technology's International Center for Air Transportation.

"There are a number of backup systems both in terms of backup air traffic control facilities and backup systems on the airplane, so that even if air traffic control would totally go away, the airplanes are still able to fly," Hansman said."

Hansman said it makes sense that the FAA canceled flights and focused on landing planes that were already in the air.

"It was an inconvenience, in some sense, on the scale of a bad winter storm. But the thing that's more remarkable is how robust the system was," Hansman said. "It was able to coordinate all the airplanes in real time and get them out without difficulty."

While thousands of flight cancellations might seem like a failure, Hansman said the system is designed to prioritize safety.

Some complications arise when a control center takes responsibility for air traffic in another region, according to John-Paul Clarke, director of the Air Transportation Laboratory at the Georgia Institute of Technology.

"The controllers at each become experts in the route structure of their facility and in managing the traffic in their airspace," Clarke said. "While you can route the data and voice streams to another facility, those controllers will not be experts in controlling the airspace."

About 15 flights were cancelled at the Twin Cities' airport over the weekend; only two have been cancelled so far today, airport spokesman Pat Hogan said.

"We're still going to be seeing some delays, we'll still see some cancellations for the next few days," Hogan said. "If you're flying to that part of the country, it's still a good idea to check with the airline before you come to the airport, but the good news is there's much greater chance that your flight is going to make it then we were afraid it was going to be last week."

Traffic is ramping up again in Chicago, too.

O'Hare is currently handling about 60 percent of its usual traffic while Midway is at 75 percent.