Delta Warns Cancellations to Stretch for Days After Outage

Delta Air Lines Inc. expects to cancel more flights this week as the carrier tries to recover from a crippling technology outage.

The airline canceled more than 800 flights as of Monday afternoon, bringing its total since Friday’s meltdown to more than 4,600. Delta said it was working “around the clock” to restore operations, with more than half of its worldwide IT systems relying on Microsoft Corp.’s Windows operating system affected by the software error.

Chief Executive Officer Ed Bastian said it could be days before Delta moves past the incident, according to a video message sent to employees Monday.

Delta has fared the worst among US carriers, with most other airlines getting back on track over the weekend. The situation comes after Delta earlier this month reported worse-than-expected financial results, sending its shares tumbling.

Delta’s shares fell 3.6% as of 3:58 p.m. (July 22) in New York. The stock is up about 9% this year.

The cancellations lingered into a fourth day as rival carriers American Airlines Group Inc., United Airlines Holdings Inc. and Southwest Airlines Co. parked a combined 79 planes as of mid-afternoon New York time, according to flight-tracking website FlightAware.

The trouble began Friday with an outage caused by CrowdStrike Holdings Inc. that affected Delta functions that rely on Windows, rendering the airline unable to process large volumes of changes to flights and their crews.

Delta said that one of its most critical systems that ensures all flights have crews assigned to its planes “is deeply complex and is requiring the most time and manual support to synchronize.”

The problems brought back memories of Southwest’s December 2022 meltdown during a winter storm that overwhelmed its crew-scheduling system and forced the airline to scrap more than 16,700 flights over 10 days.

US Transportation Secretary Pete Buttigieg, who was a vocal critic of Southwest for its multi-day IT issues, admonished Delta over the disruptions, saying the department had received reports of “unacceptable customer service conditions” in a post to social media platform X. Delta said CEO Bastian, who has apologized for the disruption, discussed the flight cancellation issues with Buttigieg on Sunday.