Swapping an Old Copper Wire for Fiber Made an FAA Router Flood Air Traffic Control With 1,000 Connection Attempts Every Five Seconds

Here is the sequence officials gave. A contractor, L3Harris, was switching “old copper wire to fiber at a remote FAA location while replacing a router,” according to CBS’s account of Duffy’s Saturday news conference. The new router then “began flooding other routers and overloaded the system.” Duffy put a number on it: “over 1,000 connection attempts every four to five seconds.”

Flooding is a plain networking failure, and it isn’t an attack. Think of a device that keeps knocking on every door in the building, over and over, until nobody can hear anything else. In this case the doors were other routers on the air traffic control network, and Scripps News quotes officials describing a communications outage.

The effects were bigger than one remote site. FAA Administrator Bryan Bedford said the instability spread to 17 facilities, and CBS says the flooding ran about 45 minutes before that happened. The Yahoo News live blog reports that Duffy said radar and aircraft communications were disrupted, and that the controllers’ union president, Nick Daniels, said “We know we didn’t have communications with airplanes.” Bedford said no facility went dark, but he conceded that “certain frequencies that were going in and out.”

The FAA issued a ground stop while more than 3,500 planes were in the air. By CBS’s count it lasted about four hours and 44 minutes. Other outlets give shorter or longer figures, and the exact length differs from source to source, so treat “more than four hours” as the safe version. Duffy said, “We are back at full operations.” Yahoo reports Bedford calling it the longest ground stop since 9/11, a claim only that outlet carries.

Officials were also asked the obvious question. Bedford said there was “zero evidence of anything nefarious or anything AI-related.” The FAA was still working out whether the cause was human error or a faulty router, and Duffy named installer error as one possibility. L3Harris said only, “We are supporting the FAA in its investigation.”

Duffy’s larger point was about age: “What we have is an incredibly old air traffic control system.” Yahoo reports he also said “L3Harris actually owns that network” and that there will be “a reevaluation of when we do this work.”

What nobody has said is where the router was. Officials called it “a very remote location,” and none of the outlets name the site. Nor has the FAA published a report, so everything here comes from one news conference as reported by several outlets.

The router’s location is still a secret, and the wire it replaced was just copper.