Delta Air Lines faces massive flight cancellations amid ongoing fallout from cyber outage

Delta Air Lines continues to grapple with severe operational challenges following a global cyber outage last week, resulting in the cancellation of over 600 flights on Monday, in addition to the 1,250 flights canceled on Sunday and the 3,500 previously scrapped.

The disruption has left thousands of passengers stranded across the United States, with some resorting to renting cars for long drives, while others face extended delays or trip cancellations.

As of Monday, about 16 percent of Delta's flights had been canceled, according to FlightAware, out of roughly 1,100 flights to or from the U.S. The Atlanta-based airline has been significantly impacted by the outage, which disrupted its crew tracking system. Since last Friday, the total number of canceled flights has exceeded 5,000.

Delta has not provided a clear timeline for when normal operations will resume.

The issues stemmed from a software update by cybersecurity firm CrowdStrike that caused system problems for Microsoft customers, including several airlines. While most U.S. carriers have recovered, Delta continues to struggle. Meanwhile, United Airlines canceled 9 percent of its Sunday flights, totaling 266, the second-highest among airlines.

Delta CEO Ed Bastian told customers via email that the crew tracking system was particularly affected, unable to manage the volume of changes needed after the system shutdown. He also informed employees that Delta would make tactical adjustments to schedules to maintain safety.

Transportation Secretary Pete Buttigieg has been in contact with Bastian, emphasizing Delta's obligations to its passengers and the Department of Transportation's role in enforcing those responsibilities. Buttigieg assured passengers that the department would support them by enforcing all relevant passenger protections and noted that it had received numerous complaints.

"No one should be stranded at an airport overnight or stuck on hold for hours," he said.

CrowdStrike reported that a significant number of the 8.5 million affected Microsoft devices were back online, but Delta's recovery process remains ongoing.

(With input from Reuters)