Travel across the United States ground to a halt Friday afternoon after the Federal Aviation Administration ordered a nationwide ground stop. The order went into effect at 3:54 p.m. Eastern time, triggered by a telecommunications outage affecting air route traffic control centers, the facilities that manage flights as they move across the country.
The disruption appears to have originated around O'Hare International Airport and Midway International Airport in Chicago, before the FAA extended the stoppage to airports nationwide, citing what it described as extraordinary circumstances. Domestic flights were held on the ground, and the effects rippled outward to international travel as well, with flights from European airports bound for the United States also affected during the roughly four-hour, 21-minute stoppage.
By the time the ground stop was lifted around 8:15 p.m. Eastern, nearly 8,000 flights had been canceled and more than 10,000 others delayed, including cargo flights, according to tracking of the disruption. Airports in major hubs reported long lines and crowded terminals as travelers waited for updates. The FAA said the problem stemmed from a communications issue rather than any security threat, and the agency has pushed back on suggestions that the outage was linked to a cyberattack.
Air route traffic control centers are a backbone of the US aviation system, coordinating aircraft once they leave an airport's immediate airspace. A breakdown in communication among those centers forces controllers to fall back on far more conservative spacing and sequencing, which is why the FAA opted for a full ground stop rather than a partial one. Flight schedules were expected to remain disrupted into the weekend as airlines worked to reposition aircraft and crews.
Expect continued flight delays and cancellations through the weekend as carriers recover, along with calls from lawmakers for a full accounting of what caused the telecommunications failure.
What caused the ground stop?
A telecommunications outage affected air route traffic control centers, which manage aircraft once they leave an airport's immediate airspace, forcing the FAA to halt departures nationwide.
How many flights were affected?
Nearly 8,000 flights were canceled and more than 10,000 others were delayed during the roughly four-hour disruption.