FAA reopens US departures after nationwide communications shutdown

The Federal Aviation Administration lifted its nationwide ground stop on Friday evening after a telecommunications failure halted departures across the United States for more than four hours, leaving thousands of flights cancelled or delayed.
The agency reopened the country’s airspace at approximately 8.15pm Eastern time after testing affected systems, although airlines warned that restoring schedules would take considerably longer. Aircraft and crews were displaced across the network, while passengers faced crowded terminals, extended waits and disrupted onward connections.
Transportation Secretary Sean Duffy said overloaded switches and routers in the country’s ageing air traffic control telecommunications network had produced inconsistent data, prompting authorities to suspend departures as a precaution. The disruption began at about 3.36pm, affecting radar information and communications at regional control centres and terminal approach facilities.
Duffy said controllers had not lost all radar or telecommunications capabilities. Nevertheless, instability in information used to manage aircraft movements made a nationwide restriction necessary until officials could establish that operations were safe. The FAA subsequently coordinated the gradual release of departing aircraft as individual facilities recovered.
Homeland Security Secretary Markwayne Mullin said officials had found no evidence of a cyberattack or terrorist involvement. He described the problem as apparently mechanical, while acknowledging that the investigation was continuing. Authorities also said there was no established connection between the aviation disruption and a separate Microsoft service outage.
Flight tracking data showed nearly 5,000 cancellations across the United States on Friday, alongside more than 10,000 delays involving flights within, into or out of the country. Hundreds of additional cancellations had already appeared on Saturday schedules as carriers attempted to reposition aircraft and crews.
The shutdown affected major airports from New York and Boston to Chicago, Seattle, Los Angeles and San Francisco. Passengers waited aboard aircraft unable to depart, while others queued at airline counters seeking alternative flights. Some aircraft already airborne were diverted or returned to their departure airports as controllers managed available capacity.
United Airlines announced plans to cancel most of its remaining Friday services, with exceptions for selected international flights. JetBlue also cancelled its remaining departures apart from certain Europe-bound services from New York’s John F Kennedy airport and Boston, warning that further disruption would extend into Saturday.
Air Canada cancelled its remaining Friday flights between Canada and the United States. International services were handled individually during the restrictions, while some transatlantic and Pacific departures received permission to operate before the wider ground stop ended. Flights already airborne generally continued under air traffic control supervision.
Duffy cautioned that reopening airspace would not immediately restore normal operations. Airlines faced the difficult task of rebuilding schedules after several hours in which departures had been held, connections missed and aircraft left far from their planned overnight locations. Larger passenger aircraft were expected to receive priority as traffic resumed.
The failure drew attention to the FAA’s reliance on older telecommunications technology. Duffy said the network included analogue systems and equipment unable to handle the volume of information passing through its switches and routers. He called for substantial investment in modernisation, estimating the broader replacement effort at approximately $50 billion.
Mullin also urged Congress to support improvements to aviation infrastructure, arguing that the disruption demonstrated the risks associated with outdated equipment. Neither official announced a definitive timetable for completing repairs or replacing the affected technology. Investigators had yet to provide a detailed account of the precise technical sequence that triggered the failure.
The FAA’s 22 air route traffic control centres manage aircraft travelling between airports, while terminal approach facilities coordinate flights arriving at and departing from busy metropolitan areas. Disruption to communications between these facilities can restrict departures even when individual airports remain otherwise operational.
The agency said it had accounted for aircraft during the stoppage and assessed systems before authorising renewed departures. Airports advised passengers to check directly with airlines rather than assume that the lifting of the national restriction meant individual services would leave on time.
San Francisco International Airport confirmed that the ground stop had ended and that it was returning to normal operations. The airport nevertheless urged travellers to consult their carriers for updated departure and arrival information as airlines worked through the remaining backlog throughout the evening and into the following morning.