Major US Airlines Suspend Flights Due to Communication Glitches

Several major U.S. airlines, including American Airlines, Delta Air Lines, and United Airlines, imposed ground stops on Friday morning due to communication issues. This decision came shortly after Microsoft resolved a cloud services outage that had earlier disrupted operations for several low-cost carriers.

The connection between the flight groundings and the Microsoft outage remains unclear. In addition to American and Delta, United Airlines and Allegiant Air also halted flights.

The FAA has yet to comment on the situation. Low-cost carriers such as Frontier Airlines, Allegiant Air, and SunCountry had reported earlier outages affecting their operations. Frontier announced on Thursday that it was resuming normal operations following the ground stop, while SunCountry cited issues with a third-party vendor affecting its booking and check-in systems.

U.S. Secretary of Transportation Pete Buttigieg stated that the department is closely monitoring the flight cancellations and delays, emphasizing that airlines must uphold their responsibilities to passengers. Allegiant Air confirmed that its website was down due to the Microsoft Azure issue but did not immediately provide further comments.

Data from FlightAware revealed that Frontier canceled 147 flights and delayed 212 others on Thursday. Allegiant experienced delays for 45% of its flights, while SunCountry saw delays for 23%. Microsoft reported that its outage, affecting Azure services in the Central U.S. region, began around 6 PM ET on Thursday and is investigating ongoing issues with Microsoft 365 apps and services.