A nationwide ground stop in the US grounded over 8,000 flights after a data overload disrupted air traffic control systems. The Federal Aviation Administration (FAA) lifted the ground stop, but officials warned that it would take time for operations to return to normal.

Airlines began resuming some flights by Friday evening, but planes and crews needed to be repositioned, slowing the recovery process. The disruption was attributed to a telecommunications outage that overwhelmed older systems.

Transportation Secretary Sean Duffy said the issue highlights a need for $50 billion in funding for system upgrades.

The ground stop affected thousands of travelers, disrupting family plans and work journeys. Homeland Security Secretary Markwayne Mullin said there was no indication of any “nefarious” activity behind the outage.

The National Transportation Safety Board (NTSB) also faced delays in sending an investigator to New Orleans after a tanker crash. Officials said air travel operations could return to normal in time for the Thanksgiving rush, which is one of the busiest travel periods of the year.