From AP:
The Federal Aviation Administration grounded all flights nationwide Friday afternoon because of communications problems at regional air traffic control centers.. The FAA notice said the ground stop was being imposed “due to extraordinary circumstances and for reasons of safety.”
Transportation Secretary Sean Duffy said there is a communications issue affecting the regional air traffic control centers that direct planes between airports nationwide. He said FAA technicians are investigating. This is the first nationwide ground stop since January 2023 when a key FAA computer system malfunctioned. Before that the last time had been after the Sept. 11, 2011 terrorist attacks.
From NBC:
“The FAA issued a nationwide ground stop for all U.S. airports following communication issues impacting multiple Air Route Traffic Control Centers,” the FAA said. The agency said in a statement that “FAA technicians are investigating the issue.”
Inbound international flights will be managed on a case by case basis, the FAA said. Nationwide ground stops are extremely rare. In January 2023, the FAA halted flights because of issues with a pilot alert system. Before that, traffic was halted nationwide after the Sept. 11, 2001, terror attacks.