U.S. Flights Halted for More Than 4 Hours as Probe Examines FAA Contractor’s Role
Key Facts
The U.S. Federal Aviation Administration halted departures nationwide for more than 4 hours after communications problems affected several air traffic control centers, as officials investigate the cause of the outage. Transportation Secretary Sean Duffy said they are examining whether deficient work by a contractor or a router failure caused the problem. Duffy held L3Harris Technologies, an agency contractor, responsible for the contractor’s performance during the incident. "Our contractor was not up to the moment," he said. An aviation adviser estimated that the halt affected about a quarter of the 45,000 daily flights in the United States.
Duffy did not say the investigation had established the cause, but outlined two possibilities that officials are still examining: contractor shortcomings or a router fault. He held L3Harris responsible for its performance in its role as a contractor, while determining whether the fault stemmed from the contractor’s work or the device remained part of the investigation. Duffy said a contractor was replacing part of the system’s old copper wiring with new fiber-optic cables, and that the work somehow increased pressure on the system. The upgrade work was thus linked to the outage, but the minister did not offer a definitive explanation in the reported remarks for how it occurred. The FAA had said communications problems affected several air traffic control centers and that its technicians were investigating the issue.
Officials said adding new technology to the air traffic control system had strained aging equipment, leading to intermittent gaps in communications and radar. Replacing copper with fiber-optic cables is part of an infrastructure upgrade that Duffy says is needed because the system relies on outdated equipment. He said many control towers are approaching 100 years old, and that the network had relied on old switches and routers and 1980s copper lines that were coming under strain. This picture shows the overlap between a network upgrade and continued operation of older equipment, at a time when air traffic control depends on communications and radar. The available statements did not link each intermittent gap in communications and radar individually to the November halt, but placed equipment strain among the factors behind the investigation.
As part of the upgrade, the FAA said the SMART system had expanded to the airspace covered by the country’s 22 air traffic control centers, after an initial launch in the National Capital Region during September. The expansion shows the scale of the changes underway in the surveillance system, alongside the continued use of old equipment. The FAA had said technicians were investigating communications problems that affected several centers, without attributing their cause to a specific contractor in its statement. Duffy, meanwhile, named L3Harris and held it responsible for the contractor’s performance, while the technical cause remains under examination. That puts the upgrade work and its compatibility with existing infrastructure at the center of questions surrounding the outage.
By November 14, Duffy said all FAA systems had returned to "full operations." The report said the agency comprehensively tested the systems to ensure their stability and reliability before allowing flights to resume. This indicates that air traffic returned after the systems were verified as ready, following the nationwide halt order issued because of communications problems. The November halt was the first nationwide stoppage since January 2023, when a core computer system that sends notices to pilots failed, and the second since the September 11, 2001 attacks. The published accounts described different causes for the two incidents, but both underscore that this outage brought back a broad nationwide procedure for suspending flights.
The incident comes as the United States continues to fund air traffic control upgrades. The FAA said Congress approved $12.5 billion for the project in 2025, and that miles of old copper wiring had been replaced with fiber-optic cables, with old airport radio systems being phased out. The White House is seeking congressional approval for an additional $30 billion to complete the work. The funding places the wiring and radio upgrades within a broader project, while the November halt showed that a communications outage can lead to a nationwide takeoff ban. Whether the cause was contractor shortcomings or a router failure remains among the issues officials are investigating.