The failures of America's aging air traffic control system

In the spring of 2025, controllers at the Philadelphia facility that guides planes in and out of Newark Liberty International Airport lost radar and communications twice in two weeks, the second time for about 90 seconds,^[3] while a shortage of certified controllers added to the delays.^[6] United Airlines cut 35 daily round-trip flights at Newark, citing the FAA's technology failures and staffing problems,^[7] and the FAA later limited the airport to 28 arrivals and 28 departures an hour.^[8] That month controllers in Denver lost contact with planes for 90 seconds and had to switch to backup communications.^[9] Transportation Secretary Sean Duffy announced a three-year plan to build a new air traffic control system.^[10]

The controller shortage, which has lasted more than a decade, led the Transportation Department to recruit video game players, a campaign that drew more than 2,000 candidates,^[11] and in September 2026 senators pressed the FAA to stop holding back a pay raise for controllers, which the agency said depended on efficiency benchmarks.^[12] That month the FAA began rolling out SMART, an artificial intelligence tool meant to predict and prevent delays, in the Washington region,^[13] and in November it said it would replace the floppy disks still used for weather and other critical information at more than 400 facilities by the end of 2028.^[14] Controller shortages during the 2025 shutdown are followed in their own Story.

On September 21, 2026, construction workers accidentally cut a fiber-optic line, halting flights at New York, New Jersey, Philadelphia and Boston airports.^[4] The same Philadelphia facility that had the 2025 radar outages lost its primary and backup data lines at the same time.^[4] A week later Duffy, airlines and aviation unions urged Congress to approve another $30 billion for control towers, software and other upgrades.^[15]

The November 13 ground stop came after communications issues affected multiple Air Route Traffic Control Centers, the facilities that guide planes between airports. It was lifted after more than four hours, with thousands of flights delayed or canceled and disruptions expected to last through the weekend.^[1] Homeland Security Secretary Markwayne Mullin said there was no indication of a "nefarious" attack and that the stoppage "isn't another 9/11."^[1] An airline source told CNN the problem began with network routers and cascaded nationwide,^[1] and Duffy blamed "old switches, old routers" that became overloaded with data as he asked Congress for $50 billion.^[16] Mullin said the FAA had been installing "new equipment, new technology" and "it was overwhelming the older system," while Duffy said the new equipment "did not go down," blamed Congress for not approving more money for it and warned, "you will have more of these." Officials said they were still looking for the exact cause.^[1] CBS News reported that Mullin had described new security patches overwhelming the older system's routers, that the FAA's preliminary investigation pointed to Cisco routers made between 2001 and 2006, and that sources were getting conflicting accounts, including that an update to the L3Harris-run network linking the centers had caused it to reboot. CBS also reported that a November 2023 FAA-commissioned safety review had called that network obsolete and warned that an unexpected failure could disconnect an entire regional control center.^[1] The outage came three days after the FAA expanded SMART to all 22 of its regional centers, which drew questions about a connection; the FAA has said the tool only suggests routes,^[17] and Microsoft and Air Space Intelligence, the company behind SMART, said their products were not the cause, and Duffy said the FAA's new AI system was not connected to what failed.^[1]