The US' Alaska Airlines saw flights grounded for around three hours on July 20 after an issue at its data center.

As first reported by Reuters, flights were able to resume from 11pm Pacific time following an IT outage.

At the time of reporting, it was not known that the issue was data center-related.

Alaska Airlines said: "As we reposition our aircraft and crews, there will most likely be residual impacts to our flights. It will take some time to get our overall operations back to normal," the Seattle-based company said.

The Airline has since added that the issue occurred when "a critical piece of multi-redundant hardware at our data centers, manufactured by a third-party, experienced an unexpected failure." There was no hacking involved, nor was it related to the recent attacks on Microsoft's server software.

The failure brought down several of Alaska Airlines' key systems, and the carrier is now working with its vendor to replace the failed hardware.

According to Alaska Airlines' 2024 Annual Report, it operates a data center in one of the several owned or leased buildings near Seattle-Tacoma International Airport. The report adds: "We also lease operations, training, administrative, and data center facilities in Burlingame, CA; Long Beach, CA; Honolulu, HI; Portland, OR; Puyallup, WA; Quincy, WA; Renton, WA; Seattle, WA; and Spokane, WA."

Most of the carrier's flights impacted were at its hub in Seattle, but also extended to other airports in the US.

Last month, Alaska Airlines Group-owned Hawaiian Airlines had its IT systems disrupted during a hacking incident.

Airlines are heavily impacted by disruptions to their IT equipment or other digital infrastructure.

In July 2024, a worldwide CrowdStrike outage took down several airlines, with Delta Airlines in particular forced to cancel more than 6,000 flights.

Later that year, British Airways had to delay flights across Europe due to a technical issue. BA has suffered numerous outages, including one in 2023 that saw more than 175 flights canceled. In December 2022, a large number of long-haul flights were impacted by a different outage. Short-haul flights were grounded earlier that year, during a lengthy and disruptive outage in February.