Duffy Ties FAA Ground Stop to L3Harris Router Work on Aging Copper Lines
Duffy says a router flooded the air traffic network during L3Harris copper-to-fiber work. The network stays L3Harris's until a replacement the FAA has scheduled for 2028, and who approved a Friday-afternoon cutover is still unanswered.
A router swapped during routine L3Harris work moving FAA lines from copper to fiber at a remote site set off Friday's nationwide ground stop, Transportation Secretary Sean Duffy said.
The Federal Aviation Administration halted departures at every U.S. airport at 3:54 p.m. ET on Friday, Nov. 13, after radar and radio links at 17 of its 22 en route centers went erratic. The stop lifted four hours and 21 minutes later; FlightAware counted more than 9,000 cancellations Friday and more than 6,000 on Saturday.
We haven't determined what the fault was,
Duffy said at a Saturday briefing, after naming L3Harris as the contractor. That leaves Thanksgiving travel, on Thursday, Nov. 26, riding on a network the company owns, with a replacement scheduled for December 2028.
The paper record does more than either side's talking points to explain how router work could stop the country.
On Friday night, Duffy blamed age at a White House news conference: We use 1980s little copper lines. It's an old system that went down and went down everywhere.
By Saturday the story had a site and a company.
Post by @SecDuffy
In at least one of our remote FAA locations, a contractor was doing routine maintenance to switch telecommunication lines ... from old copper wire,
Duffy said. The job was a move from TDM to IP, he said, meaning from analog to digital.
TDM, or time-division multiplexing, is the older way of carrying many signals down one line. An independent FAA safety review team wrote in 2023 that the phone companies no longer support it.
Either through contractor error or a faulty piece of equipment, that router that was being replaced ... it started flooding other routers in our air traffic control system,
Duffy said. He put the flood at 1,000 connection attempts every four to five seconds.
Once the work was isolated, Duffy said, systems came back online. So, we don't believe this was cyber at all.
The two versions are different diagnoses. Age is a budget problem. A job raises the question of who did it, when and with whose sign-off.
A network the FAA doesn't own
L3Harris actually owns that network,
Duffy said. At the briefing he was blunter: I can't go somewhere else. They own it.
That is a contract fact. In July 2002 the FAA awarded Harris Corp. the contract for the FAA Telecommunications Infrastructure, or FTI, a network the FAA does not own,
the DOT inspector general wrote in 2010.
The inspector general described the deal as a lease set to expire in 2017. Harris merged with L3 Technologies in 2019.
The 2017 end date passed with FTI still running. Verizon won the follow-on network, FAA Enterprise Network Services (FENS), in 2023; on Aug. 11, 2026, the FAA handed the prime role to AT&T, saying a fresh competition would make the December 2028 deadline impossible to meet.
That is why Duffy said Saturday, until I can build that, I'm stuck with L3Harris, who owns this network.
L3Harris said in a statement that it, together with its telco partners and the FAA, has completed more than 70% of the planned airspace communications conversion from legacy copper wires to a fiber optic system.
The company added: We are supporting the FAA in its investigation to understand the conditions that led to the Nov. 13 ground stop of our nation's air travel.
Asked by Yahoo News whether its own employees or a partner company did Friday's work, a spokesperson said the company had nothing to offer beyond that statement.
Given the statement's own mention of telco partners, that silence is the open question.
Bryan Bedford, the FAA administrator, explained how the failure reached most of the country. No facility actually went dark,
he said at the briefing; frequencies kept going in and out.
"If that had been a single facility, we would have just worked through it... But when we saw it go to two, three, 10, 17 facilities, that's when we started to realize there was something much larger going on here."
Bryan Bedford, FAA Administrator, Nov. 14 briefing
Work at what Duffy called at least one remote site reached more than three-quarters of the centers that handle high-altitude traffic.
Aviation expert Jeff Guzzetti told NBC: That should not have happened... There should have been safeguards against that.
It has happened before, on the same network. On Nov. 19, 2009, a Harris technician misconfigured an FTI router at Los Angeles Center during a fiber migration, hitting 129 facilities instead of 21, the Transportation Department's inspector general found.
The inspector general's sharpest line was about oversight: FAA was unaware that Harris officials had configured the network in error and made other procedural errors.
By July 2023, the FAA's own risk assessment rated FTI at the highest level,
its safety review team wrote.
The parallel has limits. The 2009 cause is established; Friday's is not. What the two share is the shape: router work, mid-migration, failing far beyond its site, just under 17 years apart.
Who picked a Friday afternoon
The timing is where the record goes quiet. The Professional Aviation Safety Specialists, the union for FAA technicians, said two contractor-owned routers were being updated mid-day.
"Historically contractors have followed a protocol where FAA employees conduct a risk assessment and coordinate the maintenance of the system or equipment. PASS-represented technicians were not involved in the upgrades that led to the ground stop yesterday."
Professional Aviation Safety Specialists, Nov. 14
An FAA official said the agency did a safety assessment before the work, Al Jazeera reported. Duffy said remote sites are done in daylight and that there'll be a reevaluation of when we do this work.
"If the worst outcome is we lose all of our frequencies, well, then that work should be done when there's the fewest airplanes in the sky."
Nick Daniels, president, National Air Traffic Controllers Association, to Yahoo News
Daniels told Yahoo News that such failures often happen when required FAA safety reviews before maintenance aren't followed. He said he did not know whether that happened Friday.
Auditors had flagged the scheduling risk in writing. A September report from the Government Accountability Office found 11,389 FAA project schedules that are not integrated, placing installations at the same sites without optimizing the schedules to reduce impacts to controller operations.
It came out 60 days before the stop.
The FAA has not said who approved Friday's window.
The progress numbers don't line up either. Duffy said Saturday that We have replaced 69% of the copper communications,
while the FAA told GAO it had replaced 2,560 of 5,170 copper wires as of May.
Divide 2,560 by 5,170 and you get 49.5%. The official figure rose about 20 points in six months.
No official has said whether Duffy's figure counts the same wires.
| Date | The network behind the ground stop, on the record | Source |
|---|---|---|
| July 2002 | FAA awards Harris Corp. the FTI network contract; FAA "does not own the network" | DOT Inspector General |
| Nov. 19, 2009 | Harris router misconfiguration during a fiber migration hits 129 facilities | DOT Inspector General |
| March 2023 | Verizon wins $2.4 billion FENS contract to replace FTI | FAA safety review team; Telecom Review Americas |
| 2023 | FAA rates FTI risk "at the highest level" | FAA safety review team |
| July 2025 | Congress appropriates $12.5 billion for the new ATC system | GAO |
| April 2026 | DOT: "almost 50%" of copper wires replaced | DOT via GovExec |
| Aug. 11, 2026 | AT&T takes over FENS; deadline end of 2028 | FAA via Washington Technology |
| Sept. 14, 2026 | GAO: 2,560 of 5,170 copper wires replaced; 11,389 unintegrated schedules | GAO |
| Nov. 13, 2026 | Router during L3Harris copper-to-fiber work; 17 of 22 centers disrupted | DOT, FAA |
| Nov. 14, 2026 | Duffy: 69% of copper communications replaced | DOT |
Bedford kept Friday's job apart from the money fight: So, this is ordinary course-of-business stuff, this is not part of the Peraton-FAA $12.5 billion modernization effort.
Duffy used the outage to ask for more, telling reporters at the White House on Friday, I want $50 billion.
If Bedford is right that this was upkeep, the job Friday was not part of the program the new money would pay for.
Rep. Sam Graves (R-Mo.) and Rep. Rick Larsen (D-Wash.), the House Transportation Committee's leaders, said jointly that the committee will thoroughly review the issues that led to this nationwide ground stop.
Sen. Tammy Duckworth (D-Ill.) pushed back on X at Duffy's blaming of Congress: You've literally controlled Congress for the past two years.
Outgoing House Speaker Mike Johnson told Fox News, We don't really need any investigation to understand we need further investment.
What travelers are owed
The cause doesn't change the refund. Under the federal refund rule, a carrier must return the full fare and fees on a cancelled flight if the passenger declines rebooking or a voucher, regardless of the reason,
the Transportation Department says.
A domestic flight moved by three hours or more qualifies too. Refunds are due within seven business days for credit card purchases and 20 calendar days for debit cards, cash and other payments.
Hotels and meals are a different matter. The department lists them as Commitments airlines make when they cause a cancellation.
For cancellations the airline did not cause, such as an FAA ground stop, its general advice is to ask airline staff if they will pay for meals or a hotel room
.
That is the gap in what airlines owe passengers.
Bedford said all passengers will be put on new flights or refunded, but told them to contact their airlines directly. Airlines have issued waivers to rebook later at no cost.
Bedford also said he expects a very transparent hearing.
Democrats take over both chambers in January, so the first one may be run by the party that didn't write the modernization money.
