Delta Air Lines continued to struggle to restore operations on Monday, three days after a global cyber outage disrupted flights around the world and stranded thousands of passengers across the country.
The Atlanta-based airline canceled 828 flights, about 21% of its total scheduled flights, as of 4:15 p.m. ET on Monday. Flight AwareThis accounted for roughly half of all canceled flights.
The company’s shares closed down 3.5% at $43.83. By contrast, turmoil at other major U.S. airlines has largely subsided.
A software update by global cybersecurity firm CrowdStrike caused system outages for Microsoft customers, including many airlines, on Friday.
A Delta spokesman did not immediately respond to a request for comment.
Delta Air Lines CEO Ed Bastian said over the weekend that the outage affected one of the airline’s crew tracking tools and that the airline was “unable to effectively handle the unprecedented number of changes caused by the outage.”
In a separate memo, Delta told employees that it would continue to “strategically adjust” its schedule to ensure safety.
Delta Air Lines is widely regarded for its reliable operations, and analysts say its on-time arrival and departure performance has helped cement the airline’s position as a premium airline.
Since the outage, the airline has cancelled around 30% of its flights, according to global aviation analytics firm Cirium.
The problem infuriated customers, with many complaining that airline helplines were overwhelmed and they waited hours to receive assistance. Some were forced to rent cars to drive hundreds of miles, while others said they had to wait days for a new flight.
“I was extremely disappointed in Delta’s response,” Bob Pearlman, who had a flight booked from Honolulu to Salt Lake City, wrote on LinkedIn.
Bastian said the outage hit the airline on its “busiest weekend of the summer” and limited its ability to re-accommodate passengers.
In a staff memo seen by Reuters, Delta said it was “taking all steps” to stabilize staffing and was raising incentive pay for pilots and flight attendants.
“The greatest help you can give at this time is to participate in a trip at any base,” the memo said, asking crew members to volunteer for additional trips.
Transportation Secretary Pete Buttigieg said Sunday that his office has received hundreds of complaints about Delta’s customer service and has urged the company to provide customers with prompt refunds, free rebookings and timely refunds.
“No one should be stuck at an airport overnight or waiting hours to speak to a customer service representative,” he said.
