Aurora FAA facility 1 of 21 high altitude centers in U.S.

CHICAGO -- The FAA center in Aurora directs thousands of flights across the country.

Following the fire at the facility, a ground stop was put in place at O'Hare and Midway airports as officials scramble to re-route planes.

Thousands of flights were canceled at both of Chicago's airports: 400 at Midway, 1,400 at O'Hare. But the effect could be felt across the nation.

The Aurora facility is one of 21 air route traffic centers in the U.S. that deal with flights at high altitudes, according to UIC transportation engineer Professor Bo Zou, who researches air traffic patterns.

"This gives rise to the issue of whether there are enough air traffic controllers to handle the added traffic. There is very stringent regulation by the FAA as to how many hours that these air traffic controllers can work and how many flights each traffic controllers can handle at each time period," Prof. Bo Zou, UIC transportation engineer, said.