One router, 20,000 flights: FAA says U.S. air travel recovers by Sunday
More than 20,000 flights have been disrupted since a single L3Harris router flooded the FAA network on Friday, and officials say schedules should be back to normal by Sunday.
A single router stopped the country
On Friday afternoon, trouble in the American air traffic system began at 3:36 p.m. Eastern time, and within the hour the Federal Aviation Administration had ordered a nationwide ground stop. For nearly five hours, no commercial flight was allowed to take off anywhere in the United States. By the time the stop was lifted on Friday evening, nearly 10,000 flights had been canceled and more than 7,000 delayed, in one of the worst travel disruptions in American history.
Saturday brought no quick recovery. More than 3,700 flights were canceled and more than 2,000 delayed as airlines worked through the backlog of aircraft and crews left out of position. United and Delta imposed their own ground stops at O'Hare in Chicago and LaGuardia in New York. Officials said schedules should return to normal by the end of Sunday, but warned that delays would linger through the weekend.
How a copper-to-fiber swap flooded the network
The cause, officials said on Saturday, was a single router installed by the defense contractor L3Harris during routine work to replace old copper telephone lines with fiber-optic cable. The new equipment began flooding the rest of the network with more than 1,000 connection attempts every four to five seconds, overloading communications at 17 of the 22 air traffic control centers that guide planes between airports. Controllers reported frequencies going in and out and had to switch between primary and backup systems.
No center went dark, officials stressed, and investigators found no sign of a cyberattack or anything malicious. What they have not determined is whether the failure came from an error during installation or from a faulty device. The transport secretary said the investigation was looking at whether the contractor made mistakes, and L3Harris said it was supporting the inquiry. The routers being replaced are about 25 years old and were supposed to have been replaced in 2006.
The $50 billion ask, and what happens next
The shutdown has become a fight over money and modernization. The transport secretary is asking Congress for $50 billion to rebuild the air traffic control system, up from $30 billion sought earlier, on top of $12.5 billion approved last year. L3Harris has completed more than 70% of the copper-to-fiber conversion, but about 30% of the old copper lines remain, and the FAA spends about $1 billion a year just maintaining them.
For passengers, there is little compensation to claim. Airlines are not required to pay for delays and cancellations caused by the FAA, because the agency, not the carriers, was responsible. The stop was the first nationwide halt since January 2023, when a contractor deleted files and stopped flights for 90 minutes, and only the second since the attacks of September 11, 2001. The system has failed before, including an eight-hour halt on the East Coast in September 2026 that disrupted 9,500 flights, and outages in Dallas and Newark in 2025. Officials say the system will fail again until it is properly rebuilt.
- More than 20,000Flights disrupted since Friday
- Nearly 10,000Flights canceled on Friday
- More than 3,700Flights canceled on Saturday
- 17 of 22Air traffic control centers affected
- $50 billionSought from Congress to rebuild the system
