Airlines slowly spooled up flying Friday morning after a far-reaching tech outage knocked many operations offline for hours, but airports remained snarled as delays and cancellations grew.
U.S. carriers including United Airlines, Delta Air Lines DAL -0.13%decrease; red down pointing triangle and American Airlines said they were resuming flights Friday morning after halting departures but warned of lingering impact as they worked to piece their operations back together and put planes and pilots into place as systems came back online.
Around 1,500 U.S. flights had been canceled as of midmorning Friday and over 4,100 globally, according to FlightAware. Delta was among the hardest hit, with about 12% of its flights scrubbed, according to Anuvu, another flight-data provider. Some carriers, including Southwest Airlines LUV -1.95%decrease; red down pointing triangle and JetBlue Airways JBLU -1.91%decrease; red down pointing triangle, had smoother operations.
The outage stemmed from an update rolled out by cybersecurity-software company CrowdStrike CRWD -9.02%decrease; red down pointing triangle, hitting millions of users of Microsoft MSFT -0.49%decrease; red down pointing triangle Windows devices worldwide. The disruption crashed computers and tablets around the world, leaving many unable to restart while displaying an error screen with a frowny-face emoji, sometimes called the “blue screen of death.”
