Transportation Department investigating Delta Air Lines as cancellations mount

The Department of Transportation is investigating flight disruptions at Delta Air Lines, which is still struggling with cancellations and delays after last week’s global data outage.

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,” Transportation Secretary Pete Buttigieg posted Tuesday on social media.

From Friday through Monday, Delta has canceled more than 5,500 flights, according to aviation data provider Cirium, as reported by The Associated Press.

As of 9:58 a.m. Tuesday, the air carrier had canceled another 438 flights, about 12% of its total for the day, and delayed 445 other flights, according to flight tracking website FlightAware.

Delta CEO Ed Bastian said the disruptions occurred on the busiest travel weekend of the summer, with 90% of seats booked on each flight.

On Friday, the cybersecurity firm CrowdStrike initiated a software update that accidentally knocked out Microsoft operating systems nationwide, affecting retailers, banks and airlines, among others. Microsoft estimates a total of 8.5 million computers were affected, according to the AP.

Many businesses have recovered, but Delta’s progress has been slow.

“Delta has a significant number of applications that use that system, and in particular one of our crew tracking-related tools was affected and unable to effectively process the unprecedented number of changes triggered by the system shutdown,” Mr. Bastian said Sunday in a statement.

“The CrowdStrike error required Delta’s IT teams to manually repair and reboot each of the affected systems, with additional time then needed for applications to synchronize and start communicating with each other,” Delta said Monday in a statement.

Delta is offering a travel waiver to affected passengers who were originally due to fly from Friday through Tuesday. Differences in fares between the original flight and a new flight will be ignored if travel is rebooked for or before this upcoming Sunday in the same level of cabin as the original flight, Delta said.

The airline is also offering refunds on request, airline miles and reimbursement for costs like hotels, ground transit and food.