US air travel struggles to return to normal after shutdown
US air travel is not expected to return to normal schedules until late on Sunday, the head of the FAA said, as the aviation system gradually recovers from a nationwide flight shutdown that officials blamed on routine maintenance gone awry.
As of 9:35 pm ET, airlines on Saturday had cancelled more than 6,400 US flights and delayed more than 8,000, according to FlightAware, an aviation website.
That followed about 9,200 flights cancelled and 7,500 delayed on Friday after the FAA ordered a nationwide ground stop because of disruptions to air traffic communications.
FlightAware said 875 flights scheduled for Sunday were already cancelled.
Federal Aviation Administration head Bryan Bedford said on Saturday that he expected airline operations to largely return to normal by late Sunday.
He also apologised for the disruption, adding that the system remains stable.
The FAA issued a nationwide ground stop on Friday that halted nearly all departing flights for almost five hours.
It was the longest nationwide halt to air travel since the attacks of September 11, 2001, and one of the single worst US travel days ever.
The issue prompted the White House to convene an emergency meeting in the Situation Room on Friday and federal agencies to scramble to determine if it was a cyberattack.
But the problem was traced to FAA contractor L3Harris’ installation of at least one new router at a remote facility, Transportation Secretary Sean Duffy said on Saturday.
“We’re working to determine whether we had incompetence, meaning, was it user error or installer error from L3Harris, or did they install a faulty router? We haven’t determined what the fault was,” Duffy said at a press conference.
The Professional Aviation Safety Specialists, a union representing FAA safety employees, said the issue was isolated to two routers that were updated Friday.
An official told Reuters it was believed the routers were in Arkansas and Texas.
An FAA official said the agency conducted a safety assessment before the work.
The union said PASS-represented technicians were not involved in the upgrades that led to the ground stop.
L3Harris said it took the issue seriously and is supporting the FAA in its investigation. Its shares last traded down about 4% after hours on Friday.
Overloaded communications centres
Duffy said the trouble began on Friday afternoon, when air traffic control centres experienced instability in radar and communications systems.
The router issue led to data overloading other communications centers, officials said.
“We had over 1,000 connection attempts every four to five seconds, and what that did was (it) gave us issues with our communication with aeroplanes, and it also caused some disruption with our radar,” Duffy added.
The issue affected communications at 17 of the FAA’s 22 en route centres, which control aircraft during the cruise portion of a flight.
Bedford said the FAA ordered the ground stop in case a centre lost all communications.
“No facilities went dark. Nothing was fully lost,” Bedford added.
The FAA said it was doing additional testing with L3Harris to see if there are any additional risks.
Delta Air Lines, United Airlines and American Airlines all cancelled about 25% of their flights on Saturday, while JetBlue cancelled nearly 45%.
Airlines have issued travel waivers allowing passengers to rebook flights for later dates without cost.
Though the FAA lifted the ground stop on Friday evening, the disruption for passengers was far from over, with tens of thousands of people stranded in airports.
Airlines were trying to get flight crews and other personnel in position to resume flights.
The disruption stranded some college football teams on Friday before games scheduled for Saturday.