Flights in the United States were resuming on Saturday after being grounded for several hours due to a major communications outage, though authorities said returning to normal operations would take time.
Friday’s nationwide ground stop sparked widespread chaos and left hundreds of thousands of passengers in limbo, with some pulled off planes moments before departure by airline staff who appeared in the dark about unfolding events.
The incident marked only the second time such an alert had been issued in US airspace — which is among the busiest in the world — since the 9/11 attacks.
On Saturday morning, effects of the stop were still felt at major hubs including New York’s JFK airport, which showed dozens of delayed and canceled flights on its website.
At Washington’s Reagan National Airport, traveler Colin Montgomery said Friday he was prepared to drive after his flight was axed.
“I got another flight that I booked for tomorrow for 6:30, just in case everything gets resolved overnight, but that seems unlikely,” Montgomery told AFP.
“We’re trying to debate whether or not we need to reschedule or drive or what, but if the whole country is stopped, that means the highways are going to be jammed too,” said Joseph Anderson, 72, who was trying to fly from Las Vegas to Oakland, California.
The ground stop lasted around four hours and was lifted at 8:15 pm Eastern Time (0115 GMT Saturday).
US Federal Aviation Administration officials reopened the airspace “after restoring full functionality” at air traffic control facilities, according to Secretary of Transportation Sean Duffy.
“It will take us time (to) resume normal operations,” Duffy said. “Our top priority is the safety of you and your family when you fly.”
Administration officials blamed the incident on telecommunications issues with decades-old equipment, adding there was no evidence of foul play.
“This is a legacy system problem,” Duffy said. “We have old, old switches, old routers.
“We use 1980s little copper lines. It’s an old system that went down, and went down everywhere. It got overloaded.”
As the ground stop was lifted, Duffy repeated his plea to Congress for $30.1 billion in funds to upgrade and modernize the air traffic control system.
– ‘Follow-on disruption’ –
There were almost 6,000 flights canceled, including some international routes, according to FlightAware. The knock-on effect has been severe, with more than 3,500 US flights already cancelled Saturday, according to the tracking platform.
“While US flights have resumed, there may be some follow-on disruption as airlines work to re-book affected passengers and get all services back to normal,” said Tim Johnson, consumer director at the UK Civil Aviation Authority.
A nationwide ground stop is highly unusual.
There was one such stop in January 2023 when a pilot notification system failed, but the only other national stop happened in the wake of the 9/11 attacks in September 2001, when no commercial aircraft flew for days.
Homeland Security Secretary Markwayne Mullin stressed there was no sign of any hostile action on Friday.
“We’ve seen zero evidence that this was a cyberattack or (AI) attack,” he told reporters.
He also ruled out any connection with the outage that affected Microsoft this week, knocking email systems offline for millions of users, public services and businesses worldwide.
– Confusion, delays –
During the outage, footage from airports showed gates full, with planes waiting on taxiways.
Passengers thronged concourses, desperate for information about an outage that had thrown their plans into chaos.
At New York’s LaGuardia Airport, Tiara Johnson said she had been trying to get to Orlando for a concert with a friend.
“They just keep delaying it… So it started out at 7:55. Then it went to 8:30, 9:30. Now it’s at 10:30. So we don’t know when it’s gonna leave,” she told AFP.
“I feel very frustrated because you know, you come to the airport and then all of a sudden your whole plans have changed and you don’t know when you’re leaving. We’re kind of stuck.”
Some travelers said they had been told their flight was delayed because of wind, while others were left to gather what information they could.
Airport boards continued to show departures leaving as normal, while mobile boarding passes held by those stuck on the ground appeared to show their flight was underway.
Stranded passengers were scrambling to find alternatives, with long lines at rental car counters at the airport in Las Vegas.
Susan Sardina said she had boarded her flight back to Orange County, California when staff told passengers there was a problem.
“We were already on our flight to leave and we were told to get off,” she told AFP while in a lengthy queue for a rental car.
