This story has been updated. Airlines canceled thousands of flights across the U.S. on Saturday as they worked to recover from a nationwide ground stop that left passengers scrambling for seats and disrupted travel around the world. The U.S. air travel schedule should be back to normal by the end of Sunday, two days after what was the nation’s longest ground stop in 25 years, Federal Aviation Administration Administrator Bryan Bedford said, declaring the “worst is behind us.” The problem began when contractor L3Harris Technologies Inc. was replacing a section of the air traffic control system’s old copper wire with new fiber wire, somehow causing the system to overload, Transportation Secretary Sean Duffy said. The work led to “intermittent” communications and radar gaps, prompting the government to shut down air traffic for more than four hours. Officials were investigating whether contractor “incompetence” or a faulty router was the cause,” he said. “Our contractor didn’t meet the moment or the equipment didn’t meet the moment,” Duffy said. L3Harris said in a statement that it was supporting the FAA in the investigation to understand what led to the ground stop and the company takes seriously the impact to travelers, airlines and air traffic operations. The FAA normally consults its own technicians in advance and asks them to assess the risks of any upgrades or repairs but that didn’t happen in this case, the Professional Aviation Safety Specialists, the union representing the agency’s technicians, said in a Saturday statement. The nationwide stop was the first since January 2023, when a key FAA computer system that sends notices to pilots malfunctioned, and the second since the Sept. 11, 2001, attacks. Andrew Charlton, an aviation consultant, said Friday’s stoppage affected about a quarter of the 45,000 flights in the U.S. each day. “The knock-on effect of that is incredible,” said Charlton, managing director of Aviation Advocacy. “The aircraft doesn’t just fly from A to B and back … and then stop. It then moves onto C and then over to E and around and around and around. It is, of course, exacerbated if you’re talking about long-haul flights, international flights over the Atlantic or over the Pacific.” Thousands of flights delayed and canceled At airports across the U.S., passengers scrambled Saturday to figure out how to reach their destinations. Some waited out the chaos in hotels while others sprinted to snag rental cars and bus or train tickets. Many camped out in airports. Others got creative. Video in Seattle’s airport showed a passenger serenading stressed out travelers with classical music. Stranded strangers in Lexington, Kentucky, participated in a cornhole tournament. The singer T-Pain and the band Hoobastank were captured on video singing to passengers as they waited on commercial airplanes. Dan Russell, 66, learned his connecting flight from Hawaii to California was canceled a half-hour before boarding was scheduled in San Diego Friday night. Hotels were full, so he and his wife waited at the airport. “There’s nothing you can do,” Russell said. At the Newark, N.J., airport, Umi Egchi was trying to figure out when he could return home to Japan. “I’m not sure exactly what happened. I just want to go home,” said Egchi, who had a sleep mask on top of his head. Sports teams that traveled for games this weekend adjusted game start times, and No. 19 Mississippi’s football game at Oklahoma was delayed to Sunday. FlightAware, a website that tracks flights, said more than 6,000 flights within, into or out of the U.S. had been canceled Saturday. Officials say no one was in danger during ground stop Duffy reiterated Saturday that no one was in danger as more than 3,000 flights in the air at the time of the grounding order landed safely. Trump administration officials blamed Congress for failing to approve more money to replace decades-old technology that helps manage air traffic. Duffy said 70% of the system had been replaced, but his agency needs new air traffic control towers and runways. The FAA has replaced thousands of old copper wires with fiber optic lines and upgraded hundreds of radio systems as part of the overhaul that began last year with $12.5 billion in funding. Duffy and the White House want $30 billion more to complete the work. “We have aging infrastructure throughout the airspace,” Duffy said, while stressing that flying remains safe. Charlton, the aviation consultant, pointed to the difficulties of updating a system that can never shut down. “What you’re watching here is trying to change the tires of your car when the car’s going at 80 miles an hour down the expressway, because nothing stops in aviation,” he said. Although Duffy said he had repeatedly spoken with President Donald Trump since the ground stop began, the president has not spoken publicly on the matter, nor issued statements via social media. He spoke on the phone with a Fox News reporter, but that was not on camera. Past problems have been linked to equipment failures The problem appeared similar to a regional air traffic control communication outage in September that snarled hundreds of flights across the Northeast. That disruption was linked to a construction crew cutting a fiber optic line. Aging equipment was also blamed for brief radar outages last year that disrupted Newark airport. Aviation safety expert Steve Arroyo said the difference Friday was the scale of the disruption that left controllers unable to reliably talk to pilots. “If you don’t have that ability, whether it’s because the old wires that they have are just run down or for whatever reason, you’ve got to stop airplanes on the ground and not put them in the air,” said Arroyo, a former United Airlines pilot. ...read more read less