U.S. Flights Resume After Nationwide Ground Stop; Canadian Travellers Warned of Lingering Delays

On Friday evening, Transportation Secretary Sean Duffy stood at a White House news conference and announced that the nationwide ground stop on U.S. flights had been lifted. In the same breath he cautioned that getting air travel moving again would be slow.

The stop followed a communications failure at air traffic control centres across the country. Duffy said the Federal Aviation Administration began seeing instability in its radar and communications systems at 3:36 p.m. ET, and that it affected facilities nationwide. Shortly before the national order, the agency had halted traffic in Chicago over communications problems. Its notice said all departing traffic should stay grounded until further notice, and that international flights would be handled case by case.

Thousands of flights were disrupted. The grounding, described in this report as only the third in American aviation history, also hit travel between the U.S. and Canada and kept some other international flights out of American airspace. Canadian airports felt it directly, with delays and cancellations at Toronto Pearson, Vancouver, Edmonton, Montreal-Trudeau, Calgary and elsewhere. Saskatoon and Regina were spared because their spokespeople said no direct U.S. flights were scheduled there for the rest of Friday.

NAV Canada, the private non-profit that runs Canada's civil air navigation system, confirmed the FAA had lifted the order. It said it would keep Canadian airspace safe and efficient, warned that some delays might linger, and told passengers to check flight status with their airlines. Transportation Minister Steven MacKinnon said Ottawa was in contact with NAV Canada and monitoring the situation.

Earlier in the day, Homeland Security Secretary Markwayne Mullin spoke to reporters outside the White House and said there was no sign of a cyberattack. He called it a telecommunication outage for now and said President Donald Trump had been briefed. He urged the public not to be afraid for loved ones, adding that this was not another 9/11. At the evening briefing he repeated that nobody had been at risk. Mullin also said there was no connection to the worldwide Microsoft outage that took down Outlook email on Thursday. FEMA, he said, had activated centres and was working with airports, cities, communities and states to help stranded passengers, including people who might need medication.

Mullin said investigators were examining every possible cause, among them a new AI-powered air traffic control system called Strategic Management of Airspace, Routes and Trajectories, or SMART. Air Space Intel, the company behind it, said on social media that the ground stop was not based on or caused by SMART, any AI product, or its integration with the FAA and air traffic control. The FAA told Global News earlier in the day that its technicians were investigating.

Duffy used the moment to press for money, pointing to the age of the country's air traffic control infrastructure. He said he wanted Congress to give the department emergency funding for a new network. The outage is the latest sign of strain on a system troubled by equipment failures, communications problems and controller shortages while the FAA works to replace old equipment. Congress approved $12.5 billion for the overhaul last year, and on Friday the FAA and White House asked for another $30.1 billion.

For scale, the report notes that Friday's halt was the second nationwide ground stop of all departures since the September 11, 2001 attacks. The other came in January 2023, when the FAA paused all domestic departures for less than two hours. The cause of Friday's failure is still under review, and Congress's response to the funding request is the next thing to watch.