Delta Air Lines CEO Ed Bastian announced on Monday that the airline will need a few more days to recover from a global cyber outage that has severely disrupted its operations. Since Friday, Delta has canceled over 4,000 flights, stranding thousands of passengers, while other major U.S. carriers have largely stabilized. As of 3:30 p.m. EST on Monday, Delta had canceled over 800 flights, about 21% of its scheduled total, accounting for nearly half of all flight cancellations according to FlightAware.

The outage was triggered by a software update from cybersecurity firm CrowdStrike, which affected Microsoft customers, including numerous airlines. In a video message, Bastian and Chief Information Officer Rahul Samant assured employees that efforts are ongoing to restore normal operations, but full recovery will take a couple of more days. Bastian expressed optimism that each day will show improvement.

Delta's shares fell by 3.5%, closing at $43.83. The airline noted that about 60% of its critical applications run on Microsoft Windows, which became inoperable due to the faulty update. IT teams have been manually repairing and rebooting systems, but the crew tracker application, crucial for ensuring full crews for flights, has been the most challenging to synchronize and repair.

Despite its reputation for reliability, the outage has sparked significant customer complaints. Many passengers faced long wait times for assistance, had to rent cars to travel, or were forced to wait days for new flights. The outage coincided with the busiest travel weekend of the summer, further straining Delta's re-accommodation efforts. Delta assured that its crews are fully staffed and ready to serve customers.

In response to the crisis, Delta has increased incentive pay for pilots and flight attendants and urged staff to volunteer for extra trips. Transportation Secretary Pete Buttigieg reported receiving hundreds of complaints about Delta's customer service and has called for the airline to provide prompt refunds, free rebooking, and timely reimbursements to affected customers.