The Federal Aviation Administration (FAA) suspended departures from airports across the United States on November 13, 2026, after technical problems disrupted radar and communications systems used by air traffic controllers. The nationwide ground stop lasted more than four hours and caused thousands of flight delays and cancellations.
What Caused the Nationwide Ground Stop
The disruption began at around 3:36 p.m. Eastern Time, when air traffic control centers and Terminal Radar Approach Control (TRACON) facilities experienced intermittent problems with radar data and communications with aircraft. The FAA ordered a nationwide ground stop at approximately 3:54 p.m. as a precaution.
Transportation Secretary Sean Duffy said outdated telecommunications equipment was responsible for the failure. The network still relies on analog Time-Division Multiplexing (TDM) technology, copper connections and switches and routers dating back several decades. The equipment became overloaded with data and began transmitting inconsistent information.
More than 3,500 aircraft were in the air when the restrictions began. Controllers used established safety procedures to bring them to the ground. Emergency medical, law enforcement and other critical flights were allowed to continue operating.
The FAA lifted the ground stop at 8:15 p.m. Eastern Time. However, the resumption of departures was gradual. Airlines faced additional disruption as aircraft and crews were out of position. More than 15,000 flights were delayed or canceled, while at least 827 flights were diverted. The disruption potentially affected more than 1.5 million passengers.
Was the Failure Connected to the FAA’s SMART System?
The incident occurred three days after the FAA announced the expansion of its SMART (Strategic Management of Airspace, Routes and Trajectories) system to all 22 regional air traffic control centers.
SMART uses flight, weather and airspace information to help controllers anticipate congestion and make routing decisions. However, Duffy said the new technology was not connected to the legacy equipment involved in the failure. The system continued operating normally and was not responsible for the outage.
Plans to Upgrade US Air Traffic Control
The incident has renewed calls for investment in the country’s aging aviation infrastructure. President Donald Trump has requested $30 billion for the modernization program, while Duffy said he wants Congress to provide $50 billion. Another $12.5 billion has already been allocated to the project.
Homeland Security Secretary Markwayne Mullin said officials had found no evidence of a cyberattack during the initial investigation. Authorities are still working to establish the exact cause of the failure and prevent similar disruptions.
The United States has experienced major air traffic control disruptions before, including staffing shortages during the 2025 federal government shutdown. Read more about the staffing problems that affected US air traffic control.