Department of Transportation Secretary Pete Buttigieg announced on Tuesday that Delta Air Lines is under investigation days after the company tried to return to normal following last week's tech outage.
The outage, which disrupted systems ranging from travel, banking and other industries, was caused by a failed software update to computers using Microsoft operating systems. While other airlines have largely recovered from Friday's outage, Delta has struggled to resume normal service.
According to travel tracker FlightAware, 30% of Delta flights were canceled on Monday, in addition to 46% that were delayed. American Airlines and United Airlines only had about 2% of its flights canceled on Monday, FlightAware said.
Additionally, 12% of Delta flights were canceled for Tuesday, as of 9 a.m. ET, with the list continuing to grow.
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On Tuesday, Buttigieg said that the Transportation Department "has opened an investigation into Delta Air Lines to ensure the airline is following the law and taking care of its passengers during continued widespread disruptions. All airline passengers have the right to be treated fairly, and I will make sure that right is upheld."
Buttigieg said on Sunday that the Transportation Department received hundreds of complaints from customers of "unacceptable customer service donations" involving Delta.
"Delta must provide prompt refunds to consumers who choose not to take rebooking, free rebooking for those who do, and timely reimbursements for food and hotel stays to consumers affected by these delays and cancellations, as well as adequate customer service assistance," Buttigieg said.
Delta CEO Ed Bastian issued an apology on Sunday to customers impacted by the glitch.
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"The technology issue occurred on the busiest travel weekend of the summer, with our booked loads exceeding 90%, limiting our reaccommodation capabilities," he said. "I want to apologize to every one of you who have been impacted by these events. Delta is in the business of connecting the world, and we understand how difficult it can be when your travels are disrupted."
Scripps News has contacted Delta for its reaction to Buttigieg's announcement and is awaiting a response.
Buttigieg encouraged consumers who believe Delta has not complied with passenger protection obligations to contact the Department of Transportation.
