US air travel gradually resumes after four-hour nationwide FAA ground stop

Air travel across the United States began to recover on Saturday after the Federal Aviation Administration ended a four-hour nationwide ground stop that had delayed or cancelled thousands of flights. Flight tracking data showed that over 3,000 flights within, into or out of the country were still cancelled early Saturday.

Transportation Secretary Sean Duffy said the interruption was triggered by an ageing air-control system that became overloaded with data, causing inconsistent information from routers. > "Because of that, we shut the system down," he said, adding that it would "take us time" to resume normal operations and that the "top priority is the safety of you and your family when you fly."

Homeland Security Secretary Markwayne Mullin noted that there was "no indication as of yet" that the communications failure resulted from a malicious attack. The grounding, the longest nationwide stop in 25 years, left passengers stranded at major airports, including Boston, Washington DC, New York and Miami.

The disruption also affected sports schedules, prompting the Southeastern Conference to move a Mississippi-Oklahoma football game to Sunday and leading to the postponement of a men’s college basketball matchup between UNC-Greensboro and Cornell.

In a Saturday statement, Duffy said operations were "slowly returning to normal this morning" but warned that travelers would continue to see delays and cancellations as airlines re-schedule flights and reposition aircraft and crews. He announced a news briefing for 10:30 a.m. ET.

The UK Civil Aviation Authority cautioned that while US flights had resumed, follow-on disruptions were possible and advised passengers traveling between the UK and the US to check with their airlines before heading to the airport.

During a Friday briefing, officials urged Congress to fully fund a complete replacement of the air-traffic control system.