MICROSOFT is investigating a cloud services outage that grounded planes and disrupted flight operations in the US on Thursday (Jul 18) night, though some of the affected airlines said operations had recovered.
Denver-based Frontier Airlines, a unit of Frontier Group Holdings, grounded flights for over two hours and attributed the cause to issues with Microsoft’s services. It lifted a nationwide pause on departures and started the process of resuming flights from 11 pm New York time.
The outage also affected reservations and bookings for another discount carrier, Allegiant Air, which operates around 130 aircraft and said it’s working on resolving issues. Leisure carrier Sun Country Airlines Holdings, with a fleet of almost 50 aircraft, similarly reported a “global outage”, without specifying its vendor.
Microsoft’s status pages showed its Azure cloud and Microsoft 365 services had problems even after Frontier’s restoration of flights. The Azure issues were localised in the central US region, the software company wrote on its status page.
“We are aware of this issue and have engaged multiple teams. We have determined the underlying cause,” the page said. “We are currently applying mitigation. Customers should see signs of recovery at this time as mitigation applies across resources in the region.”
The Allied Pilots Association, the union for American Airlines pilots, said that its website was taken offline by the Microsoft disruption. Frontier Airlines earlier reported a systems issue caused by Microsoft. This impacted the carrier’s booking and check-in systems, as well as boarding pass access for passengers, causing a knock-on effect on flights. Frontier operates around 150 aircraft, according to Cirium. BLOOMBERG
