What’s going on? Widespread IT problems are currently impacting global travel. It’s believed the issue stems, at least in part, from a software update issued by software company CrowdStrike on Microsoft Windows operating systems. The CEO of CrowdStrike said in a statement obtained by CNN that the IT issue causing a global outage has been identified and a fix has been deployed.

Meanwhile, Microsoft said the “underlying cause” that led to the global outage “has been fixed,” but added that residual impact is still affecting some services. Airports, airlines and travelers across the globe continue to navigate the fall-out. Which airlines are impacted? US-based carriers American Airlines, United Airlines, Delta Air Lines, Allegiant Airlines, SunCountry and Frontier Airlines all reported issues on Friday.

American Airlines has since said it has “safely reestablished” operations, while United Airlines is resuming “some flights.” Delta Air Lines operations resumed some flight departures but additional delays and cancellations are expected Friday. The Federal Aviation Administration (FAA) said in a statement that it’s “closely monitoring a technical issue impacting IT systems at U.

S. airlines,” adding that “several airlines have requested FAA assistance with ground stops until the issue is resolved.” Ryanair, Air France and Turkish Airlines also reported issues, while KLM Royal Dutch Airlines said the outages are “ making flight handling impossible.

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