US grounds all departing flights after air traffic control communications failure

The ground stop, ordered on Friday afternoon US time, means flights already in the air may land but flights on the ground cannot take off. The FAA cited “extraordinary circumstance and reasons for safety” in its notice to airlines. US Transportation Secretary Sean Duffy said in a post on X that the FAA issued the order “following a communication issue impacting all Air Route Traffic Control Centres.” He added: “FAA technicians are investigating the issue. We will provide immediate updates as we have them.”

This is only the third time in US history that a nationwide ground stop has been ordered. The first was during the terrorist attacks of September 11, 2001, and the second was in January 2023 when the FAA's Notice to Air Missions system failed. The 2023 outage lasted about 12 hours in total, though departures resumed after about 90 minutes.

Homeland Security Secretary Markwayne Mullin told reporters at the White House that a telecommunications outage triggered the ground stop and there was no suggestion at this stage that the problem was caused by a cyberattack. "There is no indication, and we had no reason to believe as of right now, that this was a threat to the United States," he said. "This was a telecommunication outage throughout FAA." Mullin said he saw no reason to connect Friday's issue with the outage that affected Microsoft systems around the world the previous day. "We are assured that everybody is safe. Everybody that is in the air ... we're going to get you on the ground. There's no reason for the public to be afraid or scared for their loved ones. This isn't another 9/11."

Reuters reported that nearly 7000 flights across the United States had been delayed or cancelled due to the ground stop. US airspace handles around 45,000 flights a day. Airlines for America, the industry trade association, said it was in close communication with the FAA and the Department of Transportation. "Safety is always our top priority," it said. "We appreciate the patience of the travelling public and the dedication of frontline employees who are navigating this situation."

United Airlines said in a statement posted to X that flights already airborne would continue, but new domestic departures would not depart while the ground stop remained in place. International departures, it said, were being managed on a case-by-case basis by the FAA. American Airlines said: "It will be all hands on deck across American to get customers on their way as soon as possible when the FAA lifts this ground stop."

In Australia, airports reported limited immediate impact. Sydney Airport said its operations had not yet been affected, with a spokesperson advising passengers travelling to or via the United States to check with their airline. Brisbane Airport reported a one-hour delay on American Airlines flight AA008 to Dallas-Fort Worth. Qantas said there was limited impact for the airline at that stage. In Ireland, Dublin Airport said there was a possibility that flights could be impacted on Saturday morning, and Aer Lingus said it was monitoring the situation closely.

The ground stop came days after the FAA announced it would begin rolling out an artificial intelligence tool across the country to help controllers avoid delays, according to the New York Times. The tool was initially unveiled in Washington, D.C., airports two months ago on the same day air traffic communications failures grounded hundreds of flights. Mullin said investigators would look at whether there was any link, but that the system operates out of one location near Washington D.C. and just sends recommendations.

Last year, US Congress approved $12.5 billion to fix the FAA's ageing communications system, and on Friday the FAA and White House asked Congress for another $30.1 billion to address other issues. Former United Airlines pilot and aviation safety expert Steve Arroyo said the problem appeared similar to a regional air traffic control communication outage in September that snarled hundreds of flights across the north east, except this time on a nationwide scale. “If you don't have that ability, whether it's because the old wires that they have are just run down or for whatever reason, you've got to stop airplanes on the ground,” he said.