Ground stop followed updates to older L3Harris communication system: DOT’s Duffy

The longest halt of flights into U.S. airports since 9/11 came after updates to an older communication system managed by L3Harris, Transportation Secretary Sean Duffy said Saturday.

Flight disruptions continued on Saturday and could extend through the weekend as airlines raced to recover from the Federal Aviation Administration's longest nationwide groundstop since 9/11, a measure the Trump administration blamed on a communications equipment failure in air traffic control.

More than 3,700 U.S. flights were canceled Saturday and close to 2,000 were delayed as of 9:40 a.m. ET, according to flight-tracking site FlightAware. That's on top of about 9,000 U.S. flight cancellations and more than 7,000 delays on Friday, though some disruptions were due to bad weather.

Part of untangling from the ground stop includes getting aircraft where they need to be. The ground stop forced many planes to divert to other airports.

Airlines run one of the lightest schedules on Saturday and are deploying as many spare planes and crews as possible to get travelers and employees where they need to be as they're eager to start fresh for the upcoming Thanksgiving holiday period.

American Airlines, for example, is offering flight attendants extra pay to pick up trips. American and other airlines said they would change customers' tickets at no fee or fare difference if their plans were affected by the outage.

Around 3 million people would typically be scheduled to fly on Saturday, according to aviation data firm Cirium.

The FAA had halted departing U.S. flights around 4 p.m. on Friday, a ground stop that lasted more than four hours. Routers were overloaded with data and started giving air traffic control centers inconsistent information, so the U.S. issued the ground stop, Transportation Secretary Sean Duffy said at a news conference late Friday.

He blamed outdated U.S. infrastructure for the problem and said Congress needs to approve more money to overhaul the country's air traffic control. Aging equipment and a shortage of air traffic controllers have angered airline executives for years, who have complained about the cost of resulting disruptions.

It was the second time the FAA has issued a nationwide ground stop since the Sept. 11, 2001 terror attacks. Trump administration officials said it did not appear to be a cyberattack.

The U.S. has the world's busiest airspace.

"Before clearing flights to resume, we thoroughly tested our systems to confirm they were stable and that operations remain reliable," the FAA said late Friday.

The disruption also upended travel for NBA, NHL and college teams, which struggled to reach their destinations in time for games this weekend.

Duffy said college football teams traveling on charter flights could receive priority.

"I would encourage those football teams to reach out to the FAA to schedule their flight times and make sure they have games going off tomorrow," he said during a Friday press briefing.

The Southeastern Conference announced on X that some games had been moved to Sunday due to the flight disruption.