US Transportation Secretary Sean Duffy said on Saturday that an outdated communications system may have been partly to blame for the decision to suspend flights nationwide, adding that the department did not believe the problem was due to a cyberattack.
Duffy stated during a press conference that a contract worker was conducting routine maintenance work at a Federal Aviation Administration site - in a remote area - to replace communications lines that rely on old copper wires with ones that rely on fiber optics.
“The wires were so old that it was decided to take them out of service, which meant that that line was going to stop working, so it had to be replaced,” Duffy added, noting that this process is a simple “routine” procedure that has been implemented throughout the country for decades.
Duffy pointed out that it is not yet clear whether the problem resulted from an error committed by the contractor or from a defect in the equipment.
Duffy explained that the router that was being replaced began flooding other routers in the air traffic control system with intense connection requests.
He said: "We detected more than 1,000 communication attempts every four to five seconds, which led to problems in our communication with the aircraft, and also caused some disturbances in the radar data."
Duffy added that as soon as officials noticed this matter, they took the initiative to impose a “ground stop” decision and worked to isolate the problem, before reopening the airspace later the same day, stressing that the safety of travelers remains a “top priority.”
He also clarified in response to questions about whether the matter was due to a cyber attack, and said: “Was this a cyber attack? Did a foreign country attack this network? The answer is that we do not believe so.”
“Once we were able to isolate the work that was taking place at that remote location, all of our systems came back online,” he added. “This was an FAA system that fell short of requirements.”
During his speech, the Minister of Transport praised the pilots and air traffic controllers who worked during the period of suspension of flights nationwide.
He said during the conference held at the headquarters of the Department of Transportation in Washington, D.C.: “We had 3,500 planes in the air, and with the issuance of the decision to suspend flights, they were able to land all the planes safely, which is a wonderful achievement.”
He added: "I would also like to thank the cabin crew, ground teams, and airport authorities. Everyone came together yesterday."
Duffy also expressed his gratitude to passengers affected by the delays and flight cancellations, saying, "We at DOT and the FAA appreciate their patience."
In a related context, the Democratic Governor of New York State, Kathy Hochul, called on the Minister of Transportation to resign or be fired by US President Donald Trump.
“From chronic shortages of air traffic controllers to frequent communications failures, critical vulnerabilities in our aviation system have become a recurring pattern during Sean Duffy’s time in office,” the governor said in a statement on Saturday.
"Throughout this period, he was more focused on appearing on his own television show than on addressing the crisis at his agency," she continued.
Hochul called on Congress to conduct a comprehensive investigation into the circumstances of the air traffic stoppage "to ensure that this never happens again."
Earlier Saturday, the Federal Aviation Administration announced that US airspace operations had returned to normal at all air traffic control centers.
The Aviation Administration had suspended flights on Friday “due to exceptional circumstances and safety considerations,” explaining that the decision was the result of a “temporary communications failure.”
