US is investigating Delta’s flight cancellations and faltering response to global tech outage

U.S. regulators are investigating how Delta Air Lines is treating passengers affected by canceled and delayed flights as the airline struggles to recover from a global technology outage.

Transportation Secretary Pete Buttigieg announced the Delta investigation on the X social media platform Tuesday “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 added.

Delta canceled more than 400 flights Tuesday by midmorning, accounting for about two-thirds of all cancellations in the United States, according to FlightAware.

The outage began Thursday night into Friday morning, after a faulty software upgrade from cybersecurity company CrowdStrike to more than 8 million Microsoft computers around the world.

The Atlanta-based carrier has canceled more than 7,000 flights since the outage started, far more than any other airline, according to figures from FlightAware and travel-data provider Cirium.

Delta said it was cooperating with the investigation.

“We remain entirely focused on restoring our operation after cybersecurity vendor CrowdStrike’s faulty Windows update rendered IT systems across the globe inoperable,” an airline spokesperson said in a statement. “Across our operation, Delta teams are working tirelessly to care for and make it right for customers impacted by delays and cancellations as we work to restore the reliable, on-time service they have come to expect from Delta.”

Delta has said upward of half its technology systems run on Microsoft Windows, including a tool the airline uses to schedule pilots and flight attendants. That system could not keep up with the high number of changes triggered by the outage.

The Transportation Department said it launched the investigation after seeing Delta’s continued widespread flight disruptions “and reports of concerning customer service failures.”

The department said the investigation will evolve as it learns more “and processes the high volume of consumer complaints we have already received against Delta.”