The FAA has grounded all flights nationwide for only the third time in US history, and officials say a telecommunications outage, not the agency's new AI system, is the stated cause.
Transportation Secretary Sean Duffy confirmed the ground stop at 4:16 p.m. ET. More than 2,000 flights were affected, and flights headed into the US were halted too. Homeland Security Secretary Markwayne Mullin told the press the stoppage was a "telecommunications outage" and not a national security threat.
The AI question comes from timing. A report on the FAA's new Strategic Management of Airspace, Routes and Trajectories system, or SMART, had published a day before the stoppage. The FAA describes SMART as a cloud-based platform that uses AI to analyze airline schedules, weather, airport capacity and airspace conditions, then predict traffic flows and flag conflicts before they occur. The agency put the price at $875 million. It has been active in Washington, DC airspace since at least September 21, and on November 10 the FAA announced a rollout to 22 centers nationwide. By the administration's own account, it has helped reroute 180 flights.
Officials have not confirmed any connection. Asked about it, Mullin said, "You can't rule out anything at this point," and promised action once the cause is known.
That is a careful answer, not an admission. The only cause officials have named is a different kind of failure from a flawed AI prediction. A tool built to advise controllers on routing is also a different thing from the communications links that keep a national system talking. Coincidence is the default reading until investigators say otherwise.
The scale is still worth noting. The FAA's own tally credits SMART with 180 reroutes, while this stoppage touched more than 2,000 flights. The two earlier nationwide ground stops, after the September 11 attacks and during a January 2023 outage of a pilot-notification system, both led to public accounting of what failed. The open question is whether this one gets the same, including a clear statement on whether SMART played any role.