New Delhi: A communications failure on Friday forced the Federal Aviation Administration (FAA) to ground departing flights across the US. The ground stop lasted more than four hours and disrupted thousands of flights.
The failure came a day after a Microsoft outage that disrupted services. Microsoft said there was no connection between the FAA ground stop and its services, and US officials also said they saw no link between the two incidents.
The FAA announced the ground stop at 3.54pm Eastern Time (8.54pm GMT). The agency cited a communications failure affecting all 22 Air Route Traffic Control Centres. More than 3,500 aircraft were already airborne when the order was issued. Some were diverted, while others continued to their destinations.
The disruption caused more than 7,000 flight delays and nearly 9,000 cancellations ‘within, into, or out of the USA’ in a single day. The FAA reportedly lifted the restriction at 8.15pm Eastern Time. Airlines warned that operations would take time to recover.
International flights also affected
Eurocontrol suspended all US-bound flights departing from its 42 member states, including Israel, at the FAA’s request because of technical issues, according to reports. Sydney Airport also grounded some US-bound flights after the FAA’s nationwide suspension.
The disruption also affected cargo operations and sports travel. A FedEx spokesperson, Shannon Davis, said the company had plans to minimize shipping disruptions, the Associated Press reported. Several sports teams faced travel delays, while the US transportation secretary, Sean Duffy, said teams in the National Collegiate Athletic Association would be prioritized for Saturday’s games.
What caused the ground stop?
At a White House press conference, Duffy said the FAA’s aging communications network had become overloaded with data. He said its switches and routers began sending inconsistent information, affecting air traffic communications and radar operations. This forced the FAA to halt departures nationwide as a safety measure.
The US homeland security secretary, Markwayne Mullin, said the FAA had been installing new equipment and technology to modernize the network. But the new equipment overwhelmed the older infrastructure, which still relied on decades-old switches, routers and 1980s copper telephone lines, he said.
Mullin said there was no evidence of a cyberattack or a link to Microsoft’s outage. Duffy said the incident highlighted the need to replace the aging system, and urged Congress to fund its modernization.
Second nationwide ground stop since 9/11
Friday’s ground stop was only the second nationwide grounding of flights since the September 11, 2001, attacks. The previous one was in January 2023, when the FAA halted domestic departures for about 90 minutes. A failure in the Notice to Air Missions (Notam) system, which publishes safety notices for pilots, had prevented the release of essential notices.
Friday’s ground stop also followed regional communications problems in the northeastern US in September, which disrupted hundreds of flights.
Airline disruption could continue for days
Departures resumed across the US after the ground stop was lifted, but airlines still faced a backlog. Aircraft and crew members had been left at different locations during the shutdown.
According to reports, the recovery could take several days as airlines worked to restore their schedules. The disruption also comes before Thanksgiving, one of the busiest travel periods in the US.
Transportation officials expressed confidence that the aviation system would return to normal before the Thanksgiving travel rush.