FAA's Rare Nationwide Ground Stop Cancelled 5,700-Plus Flights

More than 5,700 flights were cancelled by Friday night after the Federal Aviation Administration ordered a nationwide ground stop over a communications failure at its high-altitude air traffic control facilities — only the third such stop in 25 years.

The FAA lifted the stop at around 8:15 p.m. ET, more than four hours after it began. That's longer than the January 2023 system outage, which halted U.S. departures for roughly two hours. For context: only two nationwide ground stops have hit U.S. aviation in the past quarter century — one after the 9/11 attacks, one in 2023 over a pilot alert system failure. Friday was the third.

Airlines had already scrubbed 980 Saturday flights by Friday night, according to FlightAware, and the agency warned disruptions would linger into the weekend.

What caused the ground stop?

Transportation Secretary Sean Duffy said the trouble started at 3:36 p.m. ET, when the FAA began "experiencing instability" in radar and communications at air traffic control centers and TRACONs — the Terminal Radar Approach Controls that handle flights approaching airports. About 3,500 aircraft were airborne when the failure hit.

Duffy said on X that the FAA "issued a nationwide ground stop for all U.S. airports following a communication issue impacting all Air Route Traffic Control Centers," the facilities that manage flights between airports. FAA technicians were investigating.

Homeland Security Secretary Markwayne Mullin told a televised briefing Friday night there was no indication of a cyberattack. Take that for what it's worth this early — the FAA has not identified a cause, and no timeline for full recovery has been offered.

How did the FAA manage the halt?

All departing U.S. flights were grounded. Inbound international flights were handled case by case. The agency cited "extraordinary circumstances and for reasons of safety" in its alert.

The scope matters for sellers of travel. A regional weather stop strands one hub; a nationwide stop touches every departure gate in the country at once, and the rebooking backlog lands on airline call centers, OTA support desks and corporate travel managers simultaneously.

What's the cost picture?

Hard numbers beyond cancellations weren't available Friday night. But the shape is clear: 5,700-plus cancellations on a single Friday evening, plus nearly 1,000 more already cut from Saturday schedules, before counting delays that ripple through aircraft rotations and crew positioning.

The FAA has said nothing about compensation, waivers or how quickly the system will return to normal. Airlines will likely issue rebooking waivers; the 2023 NOTAM outage, a smaller event, still took days for schedules to fully settle.

What comes next?

The FAA hasn't said what failed or whether the 2023-style pattern — aging infrastructure, single points of failure — is repeating. Expect Saturday's cancellation count to grow, and expect answers about the cause to trail the operational cleanup.

In plain terms: this was the broadest U.S. flight halt since 9/11, and travelers and travel sellers will be dealing with the fallout through the weekend.