FAA Lifts Nationwide Ground Stop After Telecom Outage Strands 1.5 Million Passengers

At 3:54 pm Eastern on a Friday, the Federal Aviation Administration ordered every departure across the United States to stay on the ground. According to Flightradar24, 4,042 flights were already in the air at that moment. They kept flying toward their destinations while everything still at the gate was held there.

The cause, the FAA said, was a communications failure affecting all of the country's Air Route Traffic Control Centers. An airline source told CNN the trouble began with network routers and then spread nationwide. Shortly before the national order, the FAA had already stopped air traffic in Chicago because of communication problems with air traffic control. Major airlines were warned that operations might stay suspended through the evening.

Transportation Secretary Sean Duffy confirmed the stoppage in a post on X. He said FAA technicians were investigating and promised immediate updates. The agency later described the problem as a temporary telecommunications outage and said it had halted departures out of an abundance of caution. Homeland Security Secretary Markwayne Mullin said there was no definite timeline for fixing it.

The scale of the disruption became clear afterward. Data firm Cirium estimated that nearly 11,000 flights were delayed or cancelled, leaving about 1.5 million passengers stranded. At airports, passengers were reportedly asked to leave aircraft shortly before departure, and airline staff themselves seemed unsure what was happening. Joseph Anderson, 72, was trying to get from Las Vegas to Oakland, California. He said that supposedly nobody was flying but the public hadn't been told. He and his companions were weighing whether to rebook or drive, though he noted that if the whole country was stopped, the highways would be jammed too.

Officials moved quickly to say this was not an attack. Mullin said the failure was not linked to any threat against the United States and had nothing to do with the Microsoft outage that disrupted businesses, public services and millions of users earlier in the week. Law enforcement sources cited by CNN said preliminary assessments pointed away from a cyberattack. President Donald Trump was briefed, and officials said all flights were accounted for. "This isn't another 9/11," Mullin said, adding that there was no indication so far of a nefarious attack. He also said officials were not ruling out anything at this point.

The shutdown was only the second nationwide halt of its kind since the September 11, 2001 attacks. After those attacks, aircraft were grounded across the country for several days. A separate, brief nationwide halt came in January 2023, after a failure in the system that notifies pilots of potential hazards.

The episode has turned attention to the condition of the air traffic control system. Former Transportation Secretary Ray LaHood, speaking from Peoria International Airport in Illinois to CNN affiliate WEEK, said "very old and antiquated" technology may have contributed. He said he assumed there had been a serious glitch with that equipment and suspected the problem began at an FAA facility. He called the ground stop "a national calamity."

The timing was pointed. Just a day earlier, Duffy and Office of Management and Budget Director Russell Vought had written to Congress asking for $30 billion to modernize air traffic control. Their letter called the investment critical to delivering a resilient telecommunications backbone for controllers, along with modern hardware and software, new control towers and upgraded airport infrastructure.

The FAA has now lifted the ground stop, and departures can resume. What remains open is the precise origin of the router failure, and whether that answer strengthens the case Congress is now being asked to consider.