FAA orders nationwide ground stop after U.S. communication outage

The Federal Aviation Administration ordered a nationwide ground stop at U.S. airports on Friday afternoon and announced it at 4 p.m., citing extraordinary circumstances and reasons of safety. The ground stop bars aircraft from taking off from departure gates and requires departing flights to remain on the ground until further notice. Transportation Secretary Sean Duffy said on X that a communication problem affected Air Route Traffic Control Centers nationwide. The Air Route Traffic Control Centers manage all flights above 18,000 feet, and there are 22 of them across the United States. Duffy said, “FAA technicians are investigating the issue.” FlightAware reported that delays or cancellations affected more than 11,000 U.S. flights. Flightradar24 said 3,100 aircraft were in the air and headed to U.S. airports earlier in the ground stop. The FAA said it would handle inbound international flights individually, one case at a time. Planes already airborne will go to other airports, and departures remain halted. Airports around the country are starting to run out of room for aircraft amid the ground stop. At Ronald Reagan Washington National Airport, gate agents and travelers refreshed phones and tried to change flights while many sat on the floor.

LAX is the fifth-busiest airport in the United States according to the Bureau of Transportation Statistics. Homeland Security Secretary Markwayne Mullin said there is no indication yet of a nefarious attack and called it a telecommunications outage as of now. Mullin said, “no indication yet that this was a nefarious act.” Federal officials have not publicly identified what triggered the communications problem, and it remains unclear whether a cyber attack played a role. Mullin said the government is not ruling anything out while it investigates the cause. Mullin said recovery from the outage is going to take some time and that no clear duration for the stoppage exists.

The FAA’s website experienced technical difficulties and was down briefly around the time of publication. The Air Traffic Control System Command Center alert was not visible on its website at press time. The Strategic Management of Airspace system, called SMART, reached 22 air route traffic control centers nationwide on Tuesday. The tool combines roughly 200 data streams covering flight paths, schedules, weather and other factors on one platform. The FAA did not immediately connect the travel disruption to the new SMART air traffic system.

A source told the New York Post that a software upgrade may have caused the stoppage. The nationwide ground stop is the second such event since Sept. 11, 2001, with the previous stop occurring in 2023 after the NOTAM system went down. The Guardian counts this as the third time all U.S. departures have been grounded, after 11 September 2001 and January 2023. The January 2023 ground stop followed a pilot notification system malfunction and lasted less than two hours. The FAA had already stopped traffic at Chicago’s O’Hare and Midway airports earlier Friday because of an equipment outage. FAA data shows more than 14,000 air traffic controllers handle more than 44,000 flights taking off from U.S. airports each day.

NAV Canada said it is monitoring the situation and that Canadian systems are not affected. Last week the FAA said its first digital air traffic control towers are now operational in Alaska and Florida. The digital tower project is part of FAA modernization intended to reduce flight delays and improve traffic flow. Congress approved $12.5bn last year to fix the FAA’s aging communications system. On Friday the FAA and White House requested another $30.1bn from Congress for additional issues. Karen Bass said she is in close contact with federal and state partners to monitor the evolving situation.

Pilots already in the air have flight plans and know how to handle such an emergency, according to ABC News contributor John Nance.