Router flood during copper-to-fiber swap grounded all US flights; AP and ANI quote Duffy blaming different culprits

Full analysis

What happened Why it matters How each country tells it Where accounts conflict Room for disagreement Our assessment Sources and evidence

What happened

On Friday, November 13, the Federal Aviation Administration issued what its statement called "a nationwide ground stop for all U.S. airports following communication issues impacting multiple Air Route Traffic Control Centers." The halt ran through Friday afternoon. AP, published by The Globe and Mail, says it lasted more than four hours. AP calls it the longest nationwide ground stop in 25 years, the second since the September 11, 2001, attacks and the first since January 2023, when a separate FAA system that sends notices to pilots failed. Homeland Security Secretary Markwayne Mullin told reporters at the White House that the more than 3,000 flights in the air when the order came all landed safely. Unlike after 9/11, aviation safety expert Steve Arroyo told AP, planes were not ordered to land immediately, and pilots could likely still talk to ground controllers at airports.

The official explanation changed overnight. On Friday, Riviera Maya News reported, Duffy said the network had been overloaded with too much data, destabilizing radar at high-altitude control centers. He blamed copper lines and legacy switches in use since the 1980s. At a Saturday news conference, which AP notes began with audio trouble that forced last-minute microphone swaps, he gave a narrower account. A contractor at a remote FAA facility was moving telecommunications from copper wiring to fiber. "Either through contractor error or a faulty piece of equipment, that router that was being replaced as we switched from copper to fibre, it started flooding other routers in our air traffic control system," he said, according to ANI’s copy in the Hindustan Times. ANI reports the router generated more than 1,000 connection attempts every four to five seconds, disrupting controller-pilot communications and radar feeds. Operations returned once the maintenance work was isolated. AP has Duffy saying investigators were weighing contractor "incompetence" against a faulty router.

Officials ruled out the darker explanations. FAA Administrator Bryan Bedford said, per ANI: "We see zero evidence of anything nefarious, and zero evidence of anything AI-related." He promised more detail once a root-cause analysis is complete. Mullin said, according to CNN, that the stop was not linked to that week’s Microsoft outage. Duffy told AP the failure involved old equipment, not the FAA’s new AI-powered prediction system.

Saturday was spent clearing the backlog. CNN reported that by 8:45 a.m. ET, Delta had canceled 20% of its scheduled Saturday flights, United 17% and American 15%. Bedford told AP that schedules should be normal by the end of Sunday and that the "worst is behind us." Duffy told CNN that recovery would be "going to be slow" but should not affect Thanksgiving. AP’s ground reporting gave the human cost. Emily Brown gave up after four hours at the Dallas airport with her 14-year-old daughter. Auburn’s football team took a bus to Mississippi State, and kickoff moved from noon ET to 4:15 p.m.

The disruption reached well beyond the US. AP reported dozens of cancellations in Canada, canceled US-bound departures from Europe and US flights listed as canceled at Heathrow. In Mexico, Quintana Roo Governor Mara Lezama reported 57 affected departures across the state’s airports. Her tourism secretariat posted US-bound flights by number, and Mexico’s civil aviation agency relayed the FAA’s lifting of restrictions. In Manila, Philippine Airlines told passengers it was monitoring its US flights.

The politics followed quickly. Duffy blamed Congress for not funding new technology. AP notes the overhaul began last year with $12.5 billion approved by Congress, and that Duffy and the White House want $30 billion more. New York Governor Kathy Hochul demanded that Duffy resign or that President Trump remove him "immediately." She said serious lapses "have become a pattern on Sean Duffy’s watch" and called for a congressional investigation.

Why it matters

The upgrade Duffy is asking Congress to fund is the work that tripped the system. AP put it directly: new technology being added overloaded antiquated equipment, a point Duffy played down. Aviation consultant Andrew Charlton told AP that the stop touched about a quarter of the 45,000 flights the US handles each day. He compared the overhaul to "trying to change the tires of your car when the car’s going at 80 miles an hour." This was not the first warning. AP links it to a September outage across the Northeast, caused by a construction crew cutting a fiber line, and to radar losses at Newark last year.

The outage also showed how far US infrastructure reaches. Some Canada-bound flights from the Caribbean and Central and South America were grounded, AP reported, because their routes cross US airspace. The editor’s brief anticipated stranded Indian travelers and a $50 billion modernization demand. Neither appears in this reporting. The Indian outlet here, the Hindustan Times, ran ANI copy about US politics with no Indian angle, and AP’s figures are $12.5 billion spent and $30 billion sought.

How each country tells it

• 🇺🇸
  krdo.com · United States · wire copy

  A short CNN update on the Saturday backlog: more than 3,600 flights canceled per FlightAware, Delta at 20%, United 17% and American 15% of their schedules, and Duffy saying recovery will be slow but should not affect Thanksgiving.
• 🇮🇳
  Hindustan Times · India · wire copy

  Leads with New York Governor Kathy Hochul demanding that Duffy resign or be fired, then gives the fullest technical account of the cause: a contractor-swapped router flooding the network with more than 1,000 connection attempts every four to five seconds.
• 🇨🇦
  The Globe and Mail · Canada · wire copy

  The most complete account: the longest nationwide ground stop in 25 years, Duffy blaming contractor L3Harris and Congress, the $12.5 billion already spent and $30 billion more sought, plus stranded travelers and canceled college football flights.
• 🇲🇽
  Riviera Maya News · Mexico · original reporting

  Counts the damage in Quintana Roo: Governor Mara Lezama reports 57 affected departures, the state tourism secretariat lists US-bound flights by number, and Mexico’s civil aviation agency relays the FAA’s lifting of restrictions.
• 🇵🇭
  The Philippine Star · Philippines · original reporting

  Built around Philippine Airlines’ Saturday advisory that it is monitoring its US flights, with brief background on the cause and on Duffy’s call for modernization funds.

Where accounts conflict

The two agency accounts of Duffy’s Saturday news conference attach the same phrase to different culprits. AP quotes him saying "Our contractor didn’t meet the moment" and reports that he blamed L3Harris Technologies. ANI quotes him saying "This was an FAA system that didn’t meet the moment" and describes the outage as a failure of the FAA’s existing infrastructure. No other source names a contractor. Duffy may have said both things. As published, though, one account puts the failure on a vendor and the other on the agency he oversees.

The cancellation tallies also differ. Both AP and CNN cite FlightAware for Saturday: AP gives more than 2,500 and CNN more than 3,600. Neither says what time its total was taken, so the gap cannot be closed from the published text. The Philippine Star’s "nearly 6,000" gives no time period and may cover both days.

Room for disagreement

The strongest case against more outages ahead is that the safeguards worked. Every airborne flight landed, the cause was isolated within hours, and Bedford expected normal schedules within two days. ANI quotes Duffy saying the copper-to-fiber transition has been under way across the country for decades. If one defective router turns out to be the cause, this was a rare event, not a sign of the risks still to come.