FAA national ground stop ends, thousands of flights canceled and delayed
A nationwide FAA ground stop on Friday halted air traffic for several hours, leading to thousands of cancellations and delays before operations resumed on Saturday.
Air traffic across the United States began returning to normal on Saturday after a rare national ground stop that forced the cancellation of thousands of flights and stranded travelers. Transportation Secretary Sean Duffy said the system was back at full operations and thanked pilots, airline staff, air traffic controllers, the FAA and passengers for their professionalism during the disruption.
The ground stop was initiated at 3:36 p.m. EST on Friday while more than 3,500 flights were airborne. The FAA ordered the stoppage "out of an abundance of caution," and all airborne aircraft were able to land safely. The order was lifted around 8:20 p.m. EST.
Flight tracking data showed that on Friday about 9,159 flights were canceled and 7,190 delayed, while Saturday saw roughly 5,000 cancellations and 5,300 delays. Officials attributed the incident to aging air-traffic-control infrastructure and legacy technology. Duffy said a preliminary investigation found that a contractor from L3Harris was replacing old copper wire with fiber and switching a router, which then began flooding other routers and overloaded the system. The router generated approximately 1,000 login attempts every four to five seconds for about 45 minutes, spreading instability to 17 facilities.
FAA Administrator Bryan Bedford described the wire upgrade as routine maintenance, noting that about 70% of the system has already been converted from copper to fiber. He said there was no evidence of a cyberattack or any nefarious activity. Senior government sources identified the hardware involved as Cisco 600 series routers manufactured between 2001 and 2006.
The Trump administration has sought additional funding for air-traffic-control modernization, requesting $50 billion after a $12.5 billion down payment secured by President Trump. Homeland Security Secretary Markwayne Mullin said there were no indications the ground stop resulted from a cyberattack.
Airlines began restoring service on Saturday. Delta announced flexible rebooking options and warned of continued delays as crews and aircraft are repositioned. American Airlines said it was taking steps toward recovery while monitoring the situation. Southwest introduced a waiver allowing customers to cancel or rebook without penalty.
The FAA expects up to 5,000 of the 41,000 flights scheduled for Saturday to be canceled, with most airlines expected to be back on schedule by Sunday.