If you’ve ever changed your own wiring at home, you know how it goes: one minute you’re jamming all your joined-up wires into a junction box; you’re sure you got everything color-coded and in the right order; and then you flip a switch and all the flights in the country are grounded for four hours, inconveniencing potentially millions of people. Oh wait, that last part only happens if you’re the FAA, or a piece of FAA equipment like a router, or an FAA contractor.
As Transportation Secretary Sean Duffy sort of explained in a Washington, D.C. press conference on Saturday, the nationwide flight grounding on Friday was all some kind of silly wiring snafu—probably, and also probably not a cyberattack.
“This was an FAA system that […] didn’t meet the moment; our contractor didn’t meet the moment. Or the equipment didn’t meet the moment, and caused the outages,” Duffy said.
Duffy didn’t exactly blame the defense and infrastructure company L3Harris, but seemed to say L3Harris’ work created the circumstances that led to the transportation meltdown. L3Harris was working on “routine maintenance to switch telecommunication lines from old copper wire, and they were bringing it over to fiber.” This all happened, Duffy said, “in at least one of our remote FAA locations.”
L3Harris, he added, owns the telecommunications network the FAA uses for flight control, and some old copper wire was, Duffy claims, so very old that it was “being discontinued, meaning that line was going to get shut down.” The switch was from “TDM to IP or from analog to digital,” Duffy said, which doesn’t quite make sense—I’m informed that the technique known as Time-Division Multiplexing (TDM) is exclusively digital, but it can indeed involve old, analog-era wiring.
Duffy’s statement gets less clear from there:
“We haven’t determined what the fault was. Was it the router or were they not doing great work for us at L3Harris, either through contractor error or a faulty piece of equipment? That router that was being replaced as we switched from copper to fiber, it started flooding other routers in our air traffic control system.
So specifically, we had over 1,000 connection attempts every four to five seconds. And what that did was gave us issues with our communication with airplanes.”
Duffy also threw lukewarm water on the idea of a cyberattack. “Did some foreign nation attack this network? And the answer to that is we don’t believe so.”
So to break all the claims down, the government doesn’t “believe” this was a cyberattack, and it had something to do with a communications router being replaced during the switchover from copper wiring to fiber optic cable. The fault was either in the work, or a bad router, and that was either the government’s fault or L3Harris’ fault. When the problem occurred in one remote FAA location, routers all over the network were flooded with signals, and the whole system had to be shut down for about four hours. And that’s why you missed your grandma’s funeral.
It was the longest flight grounding in the U.S. since 9/11, and the ripple effects are still being felt as of this writing on Saturday.
This wiring issue happened to materialize right when the FAA was switching to an AI-based air traffic control system. Nothing so far suggests the two events are related.
Shortly after publication, and L3Harris spokesperson provided the following statement:
“L3Harris has been modernizing the communications infrastructure supporting the National Airspace System in close coordination with the FAA. With safety and reliability as our highest priorities, L3Harris, 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. 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. L3Harris takes the nationwide ground stop and its impact on travelers, airlines and air traffic operations seriously.”
