(Reuters) – Major U.S. airlines including Delta Air Lines, United Airlines and American Airlines grounded flights on Friday, citing communications problems, as a global outage disrupted operations across a wide range of industries around the world.
However, American Airlines later said in a statement that it had resumed service, while Frontier Airlines and Spirit Airlines also lifted their grounding orders.
It is not clear whether the groundings reported by major U.S. airlines are linked to the outages caused by Microsoft and cybersecurity firm CrowdStrike, which have affected banking, healthcare and many other sectors.
Smaller airlines Frontier Airlines, Allegiant Air and Sun Country Airlines had earlier reported service outages.
The three major US airlines, American Airlines, Delta Air Lines and United Airlines, had earlier said they were affected by technology issues with a third-party vendor without disclosing the name of the vendor, while Frontier Airlines said a “major Microsoft technology outage” temporarily hit its operations.
“The Allegiant website is currently unavailable due to an issue with Microsoft Azure,” Allegiant said in a statement to CNN. The company did not respond to Reuters requests for comment.
The Federal Aviation Administration said in an emailed statement that it was closely monitoring the technical issues affecting U.S. airlines’ IT systems and that several airlines had requested assistance with the groundings.
US Transportation Secretary Pete Buttigieg said the department was monitoring Frontier Airlines’ flight cancellations and delays, adding that he held the airline and all other airlines “responsible for meeting the needs of their passengers.”
A total of 518 flights had been canceled and more than 720 were delayed as of 5:58 a.m. ET on Friday, according to data tracking firm FlightAware.
Microsoft said the outage began around 6pm ET on Thursday, with some customers experiencing issues with multiple Azure services in the US Central region.
Azure is a cloud computing platform that provides services for building, deploying, and managing applications and services.
Meanwhile, Microsoft said it is investigating the issue affecting a range of Microsoft 365 apps and services.
(Reporting by Maria Ponezhath and Shivani Tanna; Additional reporting by Chandni Shah, Nathan Gomes, Surbhi Mishra, Angela Christy and David Shepardson; Writing by Abinaya Vijayaraghavan and Shubham Kalia; Editing by Mrigank Dhaniwala, Varun HK and Nivedita Bhattacharjee)