The Federal Aviation Administration halted departing flights across the country on Friday, November 13, ordering a rare nationwide ground stop after a communications outage struck all 22 of the agency's Air Route Traffic Control Centers.
Parts of the system registered ATC Zero conditions, the designation used when a facility can no longer safely manage the traffic in its airspace. Roughly 3,100 aircraft were already en route when the order came down.
Those flights were allowed to continue to their destinations and land; departures were held on the ground until technicians could restore service. Transportation Secretary Sean Duffy described the problem as a "communications issue," and FAA technicians were still investigating the cause.
It was the first nationwide ground stop since January 2023, and only the second since 9/11.
AI System Rollout Three Days Earlier
Three days earlier, on November 10, the FAA announced it had expanded its AI-powered SMART tool to all 22 air route traffic control centers, completing a rollout that had begun as a limited pilot in the Washington, D.C. area.
A nationwide communications failure arriving less than 72 hours after an agency-wide software deployment invites the obvious question. Neither the FAA nor Duffy has publicly connected the two events, and as of Friday the cause remained under investigation.
What follows should be read with that caveat in front of it: no official has said the AI rollout caused the outage, and the record so far does not establish that it did.
The push for new systems carried political weight from the top. After an Army helicopter and a passenger jet collided over the Potomac River in Washington, DC, early in Trump's second term, killing 67 people, the president eventually pledged to build systems that were "brand new, not pieced together, obsolete."
That pledge became the backdrop for how Duffy and the FAA presented SMART in the months that followed, framing the tool as part of the modernization the administration had promised in the wake of the crash.
How SMART Works
SMART, short for Strategic Management of Airspace, Routes and Trajectories, is a decision-support system rather than an autonomous controller. It merges roughly 200 data streams, including weather, traffic, and airspace restrictions, and produces routing and scheduling recommendations intended to smooth the flow of flights through congested corridors.
The system was built by Air Space Intelligence under a 12-year contract valued at $875 million. FAA specialists review the tool's recommendations before they reach the floor, and local controllers decide whether to accept them. Humans remain in the loop at every step by design.
The design of it will matter as the investigation proceeds because it bears directly on how much weight the new software can fairly carry in any eventual accounting of Friday's failure. For now, what is confirmed is narrow: a nationwide communications outage, a ground stop, thousands of aircraft rerouted or held, and a cause that technicians had not yet pinned down.
Lawmakers' Warnings, Unanswered
There were concerns expressed prior to Friday’s grounding.
On October 9, more than two dozen lawmakers sent a letter to the FAA asking the agency to suspend SMART's rollout until it addressed questions about safety evaluations, personnel training, and oversight.
The letter sought specifics: details on the planned 90-day evaluation period and the standards the system would have to meet before any nationwide deployment. The FAA proceeded with the full expansion on November 10 anyway. It did not publicly respond to the lawmakers' requests before flipping the system live across all 22 centers.
The National Air Traffic Controllers Association, the union representing the controllers, has said it was not consulted on SMART's design or testing. That omission is the crux of the union's complaint: a decision-support tool built without input from the controllers who decide whether to accept its recommendations.
The airlines have landed in a more divided posture. Delta and American Airlines have publicly backed the tool while warning that an abrupt transition could trigger unnecessary cancellations, an endorsement paired with a caution about the pace.
For its part, the FAA has stressed that SMART "cannot be used to replace the critical role air traffic controllers play or take over control of an aircraft." By the FAA's description, the tool generates advisory routing information that flows through existing systems and procedures.
It does not assume day-to-day control operations, and it does not act on its own.
Weighing the Coincidence
The timing is the kind of coincidence that invites scrutiny whether or not it proves meaningful. A brand-new nationwide AI system goes live, and within 72 hours the country experiences its first communications-driven ground stop in nearly four years.
The lawmakers who warned about a rushed deployment did so in writing, weeks in advance, and received no public answer. That sequence will shape how the incident is read regardless of what technicians eventually find.
However, correlation is not causation, and the available record does not close the gap. Officials have described Friday's outage as a communications problem still under investigation, not a SMART malfunction, and no public evidence ties the two events together.
Air Space Intelligence, the company behind SMART, pushed back directly on Friday. In a post on X, the company said, "The current ground stop is not based on or a result of the SMART system, any product of ASI or our integration with FAA and ATC."
The current ground stop is not based on or a result of the SMART system, any product of ASI or our integration with FAA and ATC.
— ASI (@AirSpaceIntel) November 13, 2026