By David Shepherdson and Caroline Valetkewicz
(Reuters) – Delta Air Lines struggled to restore normal operations on Sunday after a severe outage caused by a global cyber outage last week, cancelling 1,250 more flights on top of 3,500 already grounded.
The issue has stranded thousands of Delta travelers across the United States, with some having to rent cars to drive hundreds of miles, others having to wait days for new flights, and others having to cancel their trips altogether.
The Atlanta-based airline, which canceled a third of its schedule and delayed another 1,700 flights, or 44 percent, according to FlightAware, is grappling with operational issues after an outage in its crew tracking system.
Delta Air Lines has not announced a timeline for when it will resume normal operations and has already canceled 305 flights for Monday, according to a flight-tracking website, bringing the total number of cancellations since Friday to more than 5,000.
A software update by global cybersecurity firm CrowdStrike caused system outages for Microsoft customers, including many airlines, on Friday.
While other U.S. airlines have largely recovered, Delta Air Lines has struggled to return to normal. United Airlines canceled 266 flights, or 9% of its flights on Sunday, the second-highest number among airlines.
Delta Airlines CEO Ed Bastian said the issue affected the airline’s Microsoft Windows systems, causing critical applications to go offline.
“In particular, one of our crew tracking related tools was affected and we were unable to effectively process the unprecedented number of changes caused by the outage,” Bastian said in an email to customers.
In a separate memo, he told employees that Delta would continue to “strategically adjust” its schedule to ensure safety.
Transportation Secretary Pete Buttigieg spoke with Bastian and reminded him of airlines’ responsibilities to customers and the Transportation Department’s enforcement role, according to officials.
“We will ensure that the Department of Aviation supports Delta passengers by implementing all applicable passenger protection measures,” Buttigieg said in a statement to Reuters, adding that the department has received hundreds of complaints.
“No one should be stuck at an airport overnight or waiting for hours.”
CrowdStrike said a significant number of the 8.5 million affected Microsoft devices have come back online.
(Reporting by Caroline Valetkevich and David Shepherdson in London; Editing by Sam Holmes and Clarence Fernandez)