Power outage at Atlanta Hartsfield-Jackson Airport led to 1,173 flight cancellations

Atlanta's Hartsfield-Jackson International Airport managed to bring it's electricity b ack on Sunday night, nearly 11 hours after a power outage crippled the world's busiest airport.

The lights flickered on shortly before midnight, after an exhausting day for travelers, that had left thousands stranded in dark terminals and on planes sitting on the tarmac. A ground stop in Atlanta disrupted air travel across the United States and led to cancellations of more than 1,000 flights in and out of the airport.

The outage, which affected all airport operations, started with a fire in a Georgia Power underground electrical facility, Atlanta Mayor Kasim Reed said. The electrical fire's intensity damaged two substations serving the airport, including the airport's "redundant system" that should have provided backup power, Reed said.

"We certainly understand that the outage has caused frustration and anger and we are doing everything that we can to get folks back home right away," he said at a Sunday night news conference.

Atlanta is the heart of the US air transport system, and the disruption led to 1,173 flight cancellations to and from the airport, according to flight tracking service FlightAware.

Even as the power came back, the airport and airlines can expect a logjam of passengers, delays and cancellations Monday.