5PM–The FAA now describes the cause as “a technical issue affecting telecommunications at many air traffic control facilities across the country.” The White House says there is no indication of a nefarious act, and CNN sources say early reports indicate it was not a cyberattack. The FAA advisory lists an estimated end time late Friday night, but departures remain grounded until further notice, and the FAA has not said when flights will resume. Flights already in the air were allowed to land; about 3,100 aircraft were en route to U.S. airports when the stop began. Airlines are expected to cancel and delay flights into the weekend as they catch up. This is only the third nationwide ground stop in U.S. history, after the September 11, 2001 attacks and a January 2023 failure of the FAA’s pilot alert system.
