The United States Federal Aviation Administration has lifted a nationwide ground stop that disrupted thousands of flights following a telecommunications outage affecting air traffic control systems.
The restriction, imposed on Friday over safety concerns, halted departing flights across the country for more than four hours before airspace operations resumed at 8:15pm Eastern Time (01:15 GMT on Saturday).
US Transportation Secretary Sean Duffy confirmed the reopening of the airspace but warned that normal flight operations would take time to resume.
“We’ve opened up the airspace,” Duffy said, adding, “It’s going to be slow,” as he urged passengers to check their flight status with airlines.
The disruption was triggered by a telecommunications failure affecting air route traffic control centres responsible for managing aircraft travelling across the United States.
The FAA imposed the ground stop at 3:54pm Eastern Time on Friday as a precautionary measure.
Duffy said overloaded switches and routers caused the outage, while Homeland Security Secretary Markwayne Mullin ruled out a cyberattack and assured the public that there was no danger.
“Everybody’s safe,” Mullin said, adding that the incident was not “another 9/11”.
According to FlightRadar24, more than 4,700 flights were cancelled and about 10,000 delayed on Friday, while approximately 700 additional flights had already been cancelled for Saturday.
Aviation analytics firm Cirium also reported that at least 827 flights were diverted during the disruption, with 670 returning to their departure airports and 157 redirected elsewhere.
Aircraft already airborne were allowed to continue to their destinations, while international departures were considered on a case-by-case basis.
The outage left thousands of passengers stranded at airports, with some facing prolonged delays, missed connections and additional accommodation expenses.
Aviation analysts warned that airlines could require several days to restore their schedules fully.
Duffy acknowledged the challenges facing the country’s aviation infrastructure and called for $50bn in upgrades to the air traffic control system.
The disruption also raised concerns about the reliability of the United States’ ageing aviation infrastructure, with officials acknowledging that outdated switches, routers and copper communication lines contributed to the failure.
“We have 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,” Duffy said.
A Government Accountability Office report published in September had reportedly highlighted concerns over ageing aviation infrastructure, including copper cables dating back to the 1960s, warning that delays in modernisation could trigger further disruptions.
Aviation experts also questioned why backup systems failed to prevent the nationwide shutdown, despite the industry’s reliance on redundancy to maintain safe operations.
The FAA ground stop was the second nationwide suspension of all departing flights in the United States since the September 11, 2001, attacks.
With the Thanksgiving travel period approaching, Duffy expressed confidence that aviation operations would recover before the busy holiday season.
However, passengers have been advised to confirm flight schedules with their airlines as delays and cancellations may persist even after the telecommunications issue has been resolved.
