Air traffic across the United States began returning to normal after a router replacement botched by a contractor triggered a four-hour nationwide ground stop on November 13.
Investigations into router error
Transportation Secretary Sean Duffy said investigators are examining two routers from facilities in Texas and Arkansas as the root cause of the disruption. Contractor L3Harris secured the equipment and is conducting deep diagnostics testing at a Florida facility alongside engineers from the Federal Aviation Administration, Cisco, and Juniper, according to Fox News.
Duffy said that President Donald Trump convened federal officials on Friday as the administration investigated whether the disruption could have involved malicious interference, remarking that the president was fully supportive, fully engaged, and fully tracking what was happening. In a post on Truth Social on Sunday, Trump blamed Joe Biden and demanded funding from Congress, stating that the prior administration was an Federal Aviation Administration disaster.
WATCH: @SecDuffy updates on the investigation into the nationwide ground stop and answers critics who ask where the money already appropriated went. pic.twitter.com/0omfkcUx2y
Duffy also said that a Government Accountability Office report published in September 2026 highlighted the need to modernize air traffic control systems, while noting the report observed that the modernization effort could be prioritizing speed over costs and air traffic disruptions.
During an interview on ABC’s This Week, Duffy said that the director of national intelligence, the National Security Agency, the Federal Bureau of Investigation, and the Cybersecurity and Infrastructure Security Agency were all on a call together with intelligence partners after the Federal Aviation Administration’s communication problems emerged.
The FAA has issued a nationwide ground stop for all flights. Travelers should confirm their flight status with their airline before heading to the airport.
“We think it was the installation or the router that was the bad actor,” Duffy said, as reported by Al Jazeera. “But we’re open, if we see something else, we’re gonna continue to investigate with our federal partners and law enforcement.” Duffy also said that risk assessments are performed on everything.
Professional Aviation Safety Specialists, the AFL-CIO labor union representing more than 11,000 workers at the agency, said that the technicians it represents were not involved in the upgrades that led to the ground stop, adding that the issue was isolated to two contractor-owned and maintained routers that were being updated midday.
UPDATE: We spoke with the CEO of L3Harris, and the contractor secured the two routers from the remote FAA facilities in Texas and Arkansas. L3Harris is now conducting deep diagnostics testing at their headquarters in Florida. @FAANews, Juniper, and Cisco engineers are assisting… pic.twitter.com/pdzx6qVZSf
Federal officials confirmed that the incident was not a cyberattack.
FAA ground stop disrupts thousands of flights
The Federal Aviation Administration ordered the emergency ground stop at 3:54 p.m. Eastern Time on Friday, freezing departures while planes already airborne were cleared to land. The stoppage affected 17 of the agency’s 22 en route centers, disrupting thousands of flights nationwide. Prior to the national ground stop order issued at 2:54 p.m., another stop began at Chicago Midway International Airport at 2:17 p.m.
FULL INTERVIEW: Transportation Secretary Sean Duffy tells @margbrennan that air travel should return to full capacity by the end of the day or Monday, following Friday's nationwide ground stop. pic.twitter.com/AqvAT0I0IH
Airlines faced cascading cancellations over the weekend, resulting in more than 9,000 scrapped flights on Friday and over 5,000 cancellations on Saturday. Passengers encountered long lines and sold-out airport hotels, with many paying out of pocket for alternate transit and lodging. Air Canada reported cancelling roughly 250 flights on Friday, affecting about 27,000 passengers following the Federal Aviation Administration’s order, while a spokesperson for Vancouver International Airport stated there were 54 flight cancellations Friday and another 23 related cancellations Saturday morning.
Travelers said that Air Canada did not communicate updated information in a timely manner. Passengers reported lengthy journeys, such as a traveler returning to Baton Rouge from Portland, Oregon, who spent about 12 hours in San Francisco during a 26-hour trip. Stranded travelers faced high expenses, such as a visitor to Miami who managed to book a room at the Hyde Hotel in Midtown about 15 minutes away for $621 for the night.
“Their flight was canceled last night, rebooked, canceled again and then they personally put out $2,000 to be able to fly home to Toronto today,” Elizabeth Stroud told WZTV regarding stranded travelers at Nashville International Airport.
Funding demands for infrastructure updates
Following the disruption, Duffy pressed Congress for up to $50 billion in funding to modernize the nation’s telecommunications architecture and air traffic control equipment. The request exceeds his previous $30 billion proposal and follows a $12.5 billion congressional allocation approved last year.
“With a brand new state of the art system, we wouldn't have these outages… At 8:15 tonight, eastern time, we've opened up the air space…" Secretary Mullin & Secretary Duffy provide an update on the FAA National Ground Stop. pic.twitter.com/twTyQ9UJQ0
Duffy also warned that the agency’s communications infrastructure remains outdated despite ongoing efforts to replace copper wiring with fiber-optic technology, pointing out that the system still uses an old 1980 architecture for telecom.
Democratic Senator Chris Van Hollen of Maryland criticized the administration’s management of existing funds during an appearance on The Guardian, stating that Congress has already provided the requested support. Duffy countered that the previous funding was limited in scope and contained no resources for a new telecommunications architecture.
Secretary Mullin and Secretary Duffy Brief Members of the Press on the FAA Ground Stop https://t.co/uyvQ5bVOvb
Federal Aviation Administrator Bryan Bedford said that operations are recovering, with standard schedules expected to resume close to normal on Monday.
Earlier coverage: FAA Says Airlines Can Resume Flights After Ground Stop, but Delays Continue
The nationwide FAA ground stop has been lifted. Flight delays and cancellations continue. Check with your airline for the latest information.