Flights grounded across US after air traffic communications outage

The US Federal Aviation Administration ‌grounded ​all departing flights nationwide on Friday after a communications failure hit air traffic control centers, in only the second such shutdown since the September 11, 2001, attacks. The shutdown caused chaos at airports, with airlines canceling more than 1,000 flights and delaying nearly 10,000, according to flight-tracking service FlightAware. Thousands of aircraft already in the ‌air were allowed to land, while those on the ground could not take off. The disruption quickly spread beyond the United States, forcing the cancellation of flights from Canada and Europe.

The Department of Homeland Security said there were no signs the outage was caused by a cyberattack. "There is no indication as of yet that this was a nefarious attack against us. It's just a telecommunication outage as of right now," Homeland Security Secretary Markwayne ‌Mullin told reporters outside the White House, adding that President Donald Trump had been briefed.

"There's no reason for the public to be afraid or scared for your loved ones. This isn't another 9/11," Mullin added. Mullin ‌said the department was examining all possible causes, including a new AI-powered air traffic control system.

The disruption is the latest and most dramatic sign of strain on a US air traffic control system beset by equipment and communications failures, controller shortages and aging infrastructure. Much of the FAA’s air traffic control technology is decades old. Last week, the agency said it would phase out floppy disks used to provide weather and other critical information at more than 400 facilities nationwide by the end of 2028.

From Boston to Seattle ⁠and New York ​to Los Angeles, passengers crowded airport departure halls and airline ⁠desks as departure boards filled with delays and cancellations and aircraft remained parked at gates. “I might cry at some point but not yet,” said Louise Maher, 47, who was still hoping to fly from Newark to London on Friday night despite warnings that ⁠her British Airways flight could be delayed by air traffic control restrictions.

The shutdown also left arriving aircraft stranded on taxiways as gates filled up. Airline officials said the FAA had not indicated when the ground stop might be lifted, but there were ​preliminary indications the communications issues were improving in some places.

US AIR TRAFFIC WOES The world's busiest airspace has experienced setbacks in recent years that have disrupted flights and risked safety. In January 2025, a ⁠midair collision at Ronald Reagan Washington National Airport killed 67 people. The White House and Department of Transportation urged Congress on Friday to approve a further $30.1 billion to upgrade the United States' aging airports and air traffic control system.

The FAA announced the nationwide ground stop at ⁠3:54 ​p.m ET (2054 GMT). At the time the ground stop was issued, 4,042 flights were airborne, destined for US airports, according to Flightradar24. Shortly before the announcement, the FAA halted traffic in Chicago due to air traffic control communications issues. "If the ground stop continues through the evening, it likely will take the weekend to resolve the disruptions to airlines' networks," said Robert Mann, an aviation analyst and principal of R.W. Mann & Co.

The ⁠only other nationwide ground stop since the September 11 attacks came in January 2023, when the FAA halted domestic departures for less than two hours. The outage comes amid heightened concern about aviation security worldwide after ⁠a wave of hoax bomb threats this month disrupted dozens ⁠of passenger flights across Europe, forcing unscheduled landings and prompting fighter jets to escort or intercept aircraft.

There was no immediate indication the US communications failure was related to those incidents. The US National Weather Service also said on Friday it was experiencing nationwide internet and communications issues. There was no immediate indication the two incidents ‌were connected.