The Federal Aviation Administration issued a rare nationwide ground stop Friday, essentially halting all flight operations, due to an undetermined radio communications issue affecting traffic control centers.
The order means all departing aircraft were ordered to remain on the ground at airports nationwide pending a resolution.
U.S. Transportation Secretary Sean Duffy confirmed the move on X, writing shortly after 1 p.m. Friday, “The (FAA) issued a nationwide ground stop for all U.S. airports following a communication issue impacting all Air Route Traffic Control Centers. FAA technicians are investigating the issue. We will provide immediate updates as we have them.”
There are 22 Air Route Traffic Control Centers across the country, including Palmdale. The centers control flight traffic above 18,000 feet.
An alert sent to nationwide airports and shared online by the flight-tracking site Flightradar24 stated the stop was issued “due to extraordinary circumstances and for reasons of safety.” The alert noted that all traffic should remain ground stopped until further notice, and “inbound international flights will be managed on a case-by-case basis.”
Los Angeles International Airport officials posted a notice to passengers on X advising that the ground stop was “affecting flights departing from LAX.”
“Please anticipate delays and contact your airline for flight status,” LAX officials advised.
Officials at Ontario International Airport posted on X, “Ontario International Airport is aware of a nationwide ground stop issued by the Federal Aviation Administration (FAA) due to a communications issue. We are monitoring the situation closely and will provide updates as soon as they are available. Passengers are encouraged to check with their airlines for the latest flight information.”
There was no immediate word on the cause of the communications issue or where it was located. According to various reports, shortly before the nationwide ground stop was issued, localized ground stops were issued at both Chicago-O’Hare and Midway international airports in Chicago due to an equipment outage. It was unclear if the two events were related.
According to Yahoo News, one of its reporters was on a United Airlines plane waiting to take off from LAX, and the pilot informed passengers that the ground stop could potentially be in place until 8 p.m. California time. The pilot also told passengers the communications issue began in a traffic control center in Kansas City, then spread nationwide.
Homeland Security Secretary Markwayne Mullin told reporters Friday afternoon the ground stop was issued out of an abundance of caution, stressing that while the problem was a telecommunications issue, air traffic controllers were still able to communicate, and flights already in the air were landing safely.
“There is no reason for the public to be afraid or scared for their loved ones,” Mullin said.
Mullins insisted there was no indication that the issue was the result of any sort of cyber attack or “nefarious act.”
The issue arose one day after the FAA announced an expansion of an artificial intelligence-based flight management system known as SMART — Strategic Management of Airspace, Routes and Trajectories. According to the FAA, the system that was initially rolled out in the Washington, D.C., area, was being expanded to all 22 ARTCCs “to reduce delays, reduce fuel consumption and improve the travel experience for the flying public.”
It was unclear if the expansion of that system was in any way connected to the communication issue that prompted the ground stop. Mullin said an investigation would determine if that system played any role.
Friday’s alert marked only the second time since the Sept. 11, 2001, terrorist attacks that the FAA has issued a nationwide ground stop. The last such stop occurred in 2023 when a pilot warning system went down.
The alert did not appear to be affecting flights that were already in the air, with planes continuing to land at airports across the country.