FAA Halts Departures Nationwide After Air-Traffic Communications Outage; Cause Under Investigation

At Newark Liberty International Airport, almost an hour after the Federal Aviation Administration stopped departures across the country, no announcement had come over the loudspeaker. One airport employee, walking past a coworker, said a passenger had just told her it was a nationwide ground stop. "What?" was her reaction. Around the gates, passengers huddled and worked their phones, trying to decide what to do about checked luggage.

The order came Friday, Nov. 13. The FAA directed all departing aircraft to stay on the ground until further notice, citing frequency issues across the National Airspace System and what it called extraordinary circumstances and safety concerns. Transportation Secretary Sean Duffy said the stop followed a communication problem affecting all Air Route Traffic Control Centers. In a post on X, he said FAA technicians were investigating and that updates would follow. Flightradar24 reported that the order came after an equipment outage.

Homeland Security Secretary Markwayne Mullin spoke to reporters outside the White House and described a "telecommunication outage throughout FAA." He said there was no prior indication, as of yet, of a nefarious attack, and that for now it was simply a telecommunication outage. He said the U.S. had no reason to believe it was a threat to the country and that flights were grounded out of an abundance of caution. He did not close the door on a cause such as a cyberattack or artificial intelligence intrusion. "We're not ruling anything out at this point," he said, adding that officials did not want to get ahead of themselves.

Mullin also addressed public anxiety. DHS, he said, was fielding a flood of calls asking whether this was a terrorist attack, and he told people there was no reason to worry about loved ones who were flying. He rejected any link to the recent nationwide problems with Microsoft Outlook, calling them separate issues. His priority, he said, was restoring communications and returning to normal operations while working to find the root cause. He also said a priority list would govern how planes are accounted for as they begin arriving at airports.

Just after 5 p.m. ET, the FAA posted on X that every flight had been accounted for. Aircraft already airborne were not ordered to land immediately, and international flights bound for the United States would be handled case by case. The advisory listed an effective window from 3:54 p.m. ET to 11:30 p.m. ET, but the directive says to remain grounded until further notice, so the end time guarantees nothing. The FAA gave no estimate for when normal operations would resume.

The disruption was already large. Reuters reported nearly 7,000 flights delayed or canceled, a figure combining both, with no breakdown available. The FAA had not released its own count of affected flights or passengers. At Hollywood Burbank Airport, spokesman Mike Christensen said notice arrived just before 1 p.m. local time and that he knew only that it was tied to an equipment outage. He warned that delays would build into the afternoon and urged passengers to contact their airlines. Los Angeles International Airport had halted all departures by about 1:45 p.m. Pacific, a spokesperson confirmed. At Newark, a Flight 124 to Athens announced at 4:53 p.m. ET that all groups could board, though it was unclear whether it could take off.

A ground stop is a traffic management tool that requires aircraft meeting set criteria to stay put, overriding other such measures. The FAA uses it when controllers cannot safely handle traffic, whether from severe weather, security threats, or equipment outages. Such stops usually come with little warning.

This is not the first nationwide stop since 9/11. On Jan. 11, 2023, the FAA halted departures after its Notice to Air Missions system failed. Contractors had accidentally deleted files while synchronizing the primary database with its backup. That stop lasted nearly two hours, with disruptions through the day, and investigators found no evidence of a cyberattack. Afterward the FAA added a one-hour delay between database updates. Then-acting administrator Billy Nolen declined to guarantee another failure would never happen. In September 2025, Administrator Bryan Bedford said the agency had built a new NOTAM service from the ground up.

What to watch now is when departures resume, what investigators name as the root cause, and whether this outage draws comparison with the 2023 failure.