US aviation regulators lifted orders for a total halt to all domestic departures that took place within two hours after a failure on Wednesday morning of a major flight security system.
More than 700 flights to or from U.S. airports had been canceled and more than 4,000 were delayed as of 9 a.m. Eastern, about two hours after the Federal Aviation Administration ordered a halt, according to data from FlightAware, a flight-tracking website.
The FAA ordered a rare shutdown of domestic air traffic after a failure of the Notice to Air Missions system, which provides real-time information about potential hazards to pilots and crew members.
Although the FAA is still hunting for the initial cause of the failure, it said in a tweet just before 9 a.m. that it was resuming normal flight schedules.
“Normal air traffic operations are gradually resuming in the US following an overnight disruption to the Notice to Air Missions system that provides safety information to flight crews,” the FAA wrote. “The ground stop has been lifted. We continue to look for the cause of the initial problem.
The agency ordered a rare “ground stop” after 7 a.m. ET for two hours as it struggled to restore critical security systems. But stressed that the flight in the air is safe to land, but.
A widespread ban on all flight departures is unusual. The longest preceding example followed the terrorist attacks of September 11, 2001, in which planes were used to destroy New York City’s World Trade Center.
The problem comes less than a month after bad weather caused mass disruption and thousands of flight cancellations.
The White House stressed that, while it is unclear what caused the problem, there is so far no reason to suspect that it is the result of a cyber attack.
“There is no evidence of a cyber attack at this time,” White House press secretary Karine Jean-Pierre wrote on Twitter.
Update 4: The FAA is making progress in restoring the Notice to Air Missions system after an overnight outage. Departures continue on @EWAirport and @ATLAirport due to air traffic congestion in the area. We expect departures to resume at other airports at 9 am ET.
— FAA ✈️ (@FAANews) January 11, 2023
US transportation secretary Pete Buttigieg said he had been in “contact” with the FAA about the system outage.
“The FAA is working to resolve this issue quickly and safely so air traffic can resume normal operations, and will continue to provide updates,” Buttigieg wrote on Twitter.
US President Joe Biden told reporters at the White House on Wednesday morning that he had spoken with Buttigieg.
“They don’t know why,” Biden said. “The plane can still land safely, it just can’t fly now.”
Biden, who accompanied his wife to the medical procedure on Wednesday morning, said he expected a “good understanding” of what caused the disturbance “within a few hours”.
At 6.27am ET, United Airlines announced a “ground stop” for all flights until 10am ET.
United wrote on Twitter that it is “temporarily” suspending all domestic flights and will issue an update when it hears more from the FAA.
– United Airlines (@united) January 11, 2023
Another major airline, Southwest Airlines, said it was “closely monitoring” the situation and asked passengers to check the status of their flights. American Airlines also said it was “closely monitoring” the situation.
The departure board showed that only three of the 20 flights scheduled to leave New York City’s JFK airport between 5.40am and 6.10am were able to take off.
Overall, nearly 21,500 flights were due to depart from US airports on Wednesday, according to flight data company Cirium.
Additional reporting by Lauren Fedor in Washington