Computer at O’Hare Airport Fails; Flights Delayed, Key Data Halted

The main air traffic control computer at the Federal Aviation Administration’s busiest facility failed for 16 hours, delaying hundreds of flights at Chicago’s O’Hare Airport before it was repaired early Wednesday, FAA spokesmen said.

The outage at Chicago Center in Aurora, Ill., the third since Sunday, forced controllers to manually gather some data they normally are provided via the computer.

FAA spokesman Mort Edelstein acknowledged that the outage was the third this week but added: “The air traffic control system functioned as it was designed to function in the event of a major computer failure and in no way jeopardized air traffic safety.”

A backup computer worked “perfectly” during the outage, another FAA spokesman said.

But the failure halted the flow of computer-generated flight strips, which contain information on aircraft departure and arrival times, destinations and flight routes. The backup computer does not generate the computer printout strips, which are used by controllers in the O’Hare tower.

As a result, controllers must compile the information by hand and transmit it to other controllers over the telephone--functions normally handled by the main computer.

The backup computer also does not display on controllers’ radar scopes the ground speed of aircraft or projections of a plane’s flight path, on which controllers rely to maintain required distances between aircraft in flight.