Computer outage keeps hundreds of Delta flights on the ground

Travelers throughout Delta Air Lines' global network endured widespread cancellations and long delays Monday after an electrical problem brought down critical computer systems at the company's nerve center in Atlanta.

By late afternoon, the airline had canceled 650 flights, including 40 at Minneapolis-St. Paul International Airport, where it is the dominant player. Delta said it had been able to operate only 2,340 of the nearly 6,000 flights on its schedule.

The airline's computer systems failed around 1:30 a.m. Central time, Delta said, because of a "power outage in Atlanta." Georgia Power, the electric company that supports Delta, said something went wrong with the airline's switchgear, which can be likened to a fuse box.

Delta concluded by the end of the day that "following the power loss, some critical systems and network equipment didn't switch over to Delta's backup systems."

Delta's website said at 6 p.m. Monday that its computers were fully operational, but delays and cancellations continued to ripple through the system.

Three hours later, the average wait time at Minneapolis-St. Paul International Airport was 31 minutes, according to the FlightAware.com, a real-time flight tracking website.

MSP spokeswoman Melissa Scovronski said she hadn't heard of any passengers who would be stranded at the airport overnight. But she said one news and gift store planned to stay open "so people have what they need in terms of food and water."

The average delay time at MSP midday rose to more than an hour but dropped by about half by the afternoon, according to FlightAware.com. Several of the airline's other U.S. hubs, such as Atlanta, Detroit and New York-LaGuardia, had similar delay times.

The problems occurred at Delta's headquarters, where it manages its worldwide network. While the operations and customer center never went dark, a company spokesman said, the outage disrupted the company's data feeds.

Delta was still able to communicate with pilots through radio and was still able to track all of its airplanes.

"I apologize for the challenges this has created for you," Delta chief executive Ed Bastian said on a video the company posted online Monday afternoon.

The disturbance is a significant blemish on an otherwise strong year for Delta's operational reliability, a point of pride for the company. As of last Friday, Delta had 134 days this year without any cancellations of flights operated by Delta itself, compared with 76 days at the same time last year.

He said he learned about the problem from Twitter messages around 4:45 a.m. Like other passengers, he said he had no direct communication from Delta, but surmised that might be related to the outage.

Other passengers were still trying to find out what was going on. Most were taking the delays and possible cancellations in stride, Lynch said. "It is oddly calm, subdued," he said.

Many passengers settled in for long waits as planes coming from elsewhere had yet to arrive.

Delta uses a variety of factors to determine which flights to cancel, such as where crews are needed, what airplanes have connections to make and whether any unaccompanied minors are aboard a flight.

"This is not a good problem for any large airline to have," Scovronski said earlier in the day. "We are doing our best to be sure passengers are taken care of."

And while Delta's website said his 9 a.m. flight was on time, when he checked in at the airport, he was told it was delayed.

Communication from Delta improved as the morning progressed.

Kim Serra got a text alert about an hour before her 9:15 a.m. scheduled flight to Phoenix from MSP informing her that her flight would be delayed. But by then, she was already at the airport.

"I'm only delayed about an hour and half, at least for now," Serra said. "I was expecting pandemonium but it's really not bad."

Travelers enduring cancellations or significant delays are eligible for a refund if they claim it by Friday, Delta said. Even if a passenger's flight is not canceled, Delta is letting those with tickets for Monday flights make a one-time change to their ticket at no cost.

tim.harlow@startribune.com 612-673-7768