US flight disruptions continue with more than 2,500 cancellations despite lifted takeoff halt

WASHINGTON — Widespread disruption to air traffic in the United States continued on Saturday, even after the US Federal Aviation Administration (FAA) lifted its nationwide halt on aircraft takeoffs. More than 2,500 flights were cancelled, and authorities warned that delays would continue over the coming days.

The developments followed a serious technical failure on Friday that hit US communications and air traffic control systems. Authorities suspended takeoffs for more than four hours, in one of the largest disruptions to the US aviation sector in recent years.

The responsible agencies warned travellers, including Canadians heading to the United States, that restoring regular flight schedules would take time even though the airspace has reopened.

More than 2,500 flights cancelled on Saturday

The FAA announced it was lifting the takeoff halt at about 8:15 p.m. Eastern time on Friday, after confirming that core systems were stable.

Some domestic flights began departing again, but airlines struggled to reorganize their schedules.

According to data from FlightAware, a flight-tracking website, more than 2,500 flights in the United States were cancelled on Saturday, and hundreds of delays were also recorded.

US Transportation Secretary Sean Duffy warned that air traffic would not return to normal immediately.

Officials said the effects of the shutdown could last several days because of the backlog of cancelled flights and the need to redistribute aircraft and crews.

What was the real cause of the shutdown?

The US administration said the problem began during the introduction of new technology into the air traffic control system.

It explained that the equipment upgrade overloaded older systems, causing intermittent communications disruptions and gaps in radar data.

These problems led the FAA to take the precautionary decision to halt aircraft takeoffs, to protect flight safety and prevent accidents.

The Transportation Secretary acknowledged that the scale of the failure was unexpected, warning that similar disruptions could recur if structural problems in the older systems are not addressed.

Authorities are continuing to investigate the technical details of the fault and to assess the measures needed to prevent a repeat.

Crisis exposes ageing air traffic control systems

The incident highlighted the outdated technical state of some US air traffic management systems and the need for major investment to modernize them.

The US Congress approved US$12.5 billion in 2025 to upgrade air traffic control infrastructure.

However, the Transportation Secretary and the White House are now asking for an additional US$30 billion to complete the project.

The administration believes that modernizing the systems is necessary to improve the reliability of communications and radar, and to reduce the likelihood of failures that could affect air traffic nationwide.

Did the Microsoft outage cause the crisis?

The halt in air traffic coincided with widespread disruption to Microsoft services, including the Outlook email service and other digital platforms.

The company said, however, that it had no indication of any link between the outage of its services and the air traffic control problem.

US Secretary of Homeland Security Markwayne Mullin also said there was no evidence that aviation systems had been the target of a cyberattack.

He stressed that the decision to halt flights was made out of caution and that authorities gave priority to the safety of aircraft and passengers.

Preliminary information therefore indicates that the crisis resulted from a technical problem in the infrastructure upgrade, not from a confirmed cyberattack.

What about flights between Canada and the United States?

Canadian airports were affected by the US decision, particularly flights to or from the United States.

Airports in Toronto, Montreal, Vancouver and elsewhere saw delays and cancellations, while Canadian air navigation systems continued to operate normally.

Air Canada also warned that air traffic control restrictions would continue to affect flights at Toronto Pearson and Billy Bishop airports on Saturday.

The airline said it had allowed some affected passengers to change their bookings without fees, subject to eligibility conditions and seat availability.

Passengers are advised to check the status of their flights directly with their airlines, even after the US halt was lifted.

Are travellers entitled to ticket refunds?

US authorities said travellers whose flights were cancelled can be rebooked at no additional charge if they wish to continue their trip.

Travellers who decide not to travel after a cancellation are entitled to a refund of the ticket price under US transportation rules.

Rights to compensation and additional assistance vary depending on the airline, the route, the applicable laws, and the cause of the delay or cancellation.

Canadian travellers should therefore review the terms of their bookings and keep cancellation and delay notices, as well as any additional expenses.

When will flights return to normal?

US authorities expect air traffic to return gradually to regular operations, with systems possibly returning to normal levels before the travel peak linked to American Thanksgiving.

But airlines may need several days to clear the accumulated delays and restart cancelled flights.

The FAA is continuing to monitor the performance of its systems after the repairs, while airlines work to rearrange their operations at the affected airports.