The Federal Aviation Administration grounded all US flights Friday afternoon, due to “extraordinary circumstances and for reasons of safety,” the agency said in a statement. Flights already in the air will be allowed to land, the agency said, but no new ones are permitted to take off.
In a post on X, US Transportation Secretary Sean Duffy said that the ground stop was related to a communication issue affecting Air Traffic Control Centers.
The ground stop came after widespread reports of radio frequency outages among several of the nation’s most critical Air Traffic Control Centers, including in Boston, Chicago, and New York.
The FAA has not provided any additional details, and the agency did not immediately respond to a request for comment.
Nationwide ground stops are rare. The FAA halted all air traffic on September 11, 2001. In January of 2023, a ground stop was issued after an outage to a critical system that the FAA used to distribute real-time data and warnings to pilots, known as NOTAM (Notice to Air Mission).
At San Francisco International Airport on Friday, hoards of confused travelers lined up to speak with airline staff. A number flights at the airport had already been delayed because of high winds, and the FAA ground stop was now compounding the issue.
“The FAA has issued a nationwide ground stop,” a United Airlines employee said over the intercom at Terminal 3 near the E departure gates. “This is a nationwide event.”
This is a developing story. Please check back for updates. Louise Matsakis contributed reporting.