Travelers as flights are cancelled at Ronald Reagan National Airport (DCA) in Arlington, Virginia, US, on Wednesday, Jan. 11, 2023.
Air travel disruptions eased on Thursday, a day after a severe pilot safety-alert system failure sparked the delay of close to half of U.S. flights.
The FAA said a preliminary review traced the outage to a "damaged database file."
Unable to fix the problem, the FAA rebooted the system, and ordered the ground stop, which it lifted around 9 a.m. on Wednesday.
"When there's a problem with a government system, we're going to own it, we're going to find it, and we're going to fix it," he told reporters Wednesday.