FAA lifts longest nationwide ground stop since 2001, cites overloaded legacy communications system
The Federal Aviation Administration ended a four-hour nationwide ground stop that delayed more than 8,500 flights, attributing the disruption to overload of older air-traffic control communications equipment.
The U.S. Federal Aviation Administration announced the end of the longest nationwide ground stop of flights since the September 2001 attacks. The stoppage, which began on Friday afternoon, lasted more than four hours and was described by the agency as caused by "extraordinary circumstances" stemming from a communications issue that affected all air-traffic control centers.
According to flight-tracking data, the ground stop resulted in over 8,500 delayed flights and nearly 8,000 cancellations. At the time of the announcement, more than 3,500 aircraft were airborne, with some diverted to alternate airports. Later, limited departures resumed from San Francisco International Airport, and the FAA cleared the skies again by 20:15 EST.
International traffic bound for the United States from Eurocontrol member states was suspended, affecting flights from the United Kingdom, Turkey, Israel, Morocco and other European nations. Heathrow reported cancellations and delays, while Manchester and Gatwick indicated minimal impact. Sydney Airport halted U.S.-bound departures but later expected scheduled flights to proceed. Air Canada also cancelled flights between the United States and Canada.
U.S. Transportation Secretary Sean Duffy told a news conference that the outage would have a ripple effect for several days and that it would take time to fully resolve the issue. He said the legacy air-traffic control communications system became overloaded, noting that the analogue telecom switches and routers were overwhelmed with data, affecting both communications and radar. Duffy estimated that a complete overhaul of the system could cost around $50 billion.
Homeland Security Secretary Markwayne Mullin said there was "zero evidence" of a cyber-attack and dismissed any link to the recent global Microsoft outage. Both officials emphasized that the public was not in danger during the stoppage.
Airlines began restoring service after the interruption. Delta Air Lines and United Airlines announced the resumption of operations, while American Airlines said it was focused on operating as many remaining flights as possible that evening. JetBlue planned to restart flights on Saturday morning, and British Airways advised passengers to check flight status but to travel to the airport as planned.
The incident marks the second nationwide ground stop since the immediate aftermath of the September 2001 al-Qaeda hijackings.