The US Federal Aviation Administration lifted its rare nationwide ground stop on Friday night, hours after a communications failure at air traffic control centres halted all departing flights across the country. The FAA confirmed the stop was over, ABC News reported, after a ground controller at Detroit Metropolitan Wayne County Airport told pilots at about 8:14 p.m. ET that it was “officially over in 1 minute”.
The stop had been imposed on Friday afternoon, at about 3:54 p.m. ET, after a communication issue affected all 22 Air Route Traffic Control Centers that guide planes between airports across the US. The FAA’s advisory cited “extraordinary circumstances and for reasons of safety”. It was the first nationwide ground stop since January 2023, when a key FAA computer system failed, and only the second since the aftermath of the September 11, 2001 attacks.
Homeland Security Secretary Markwayne Mullin said the problem was a telecommunications outage and that there was no indication it was a cyberattack. “There’s no indication yet that this was a nefarious attack against us. It’s just a telecommunications outage as of right now,” he told reporters at the White House. CBS News sources pointed to a software update, while an airline source told CNN the FAA blamed network routers. The exact cause has not been confirmed.
01. Thousands of flights cancelled and delayed
The disruption was huge. Nearly 5,000 flights were cancelled nationwide on Friday, according to FlightAware, and more than 10,200 were delayed, NBC News reported. At least 827 flights were diverted, according to aviation analytics firm Cirium: 670 were sent back to the airport they had departed from, while 157 were redirected elsewhere. More than 11,000 flights carrying over 1.5 million passengers had been scheduled to take off after 4 p.m. EST.
Flights already in the air were allowed to land normally, and some departures resumed in stages during the evening before the full lift. Flights to Hawaii and Asia from San Francisco were among the first cleared, along with some coastal ocean routes. Flights within Alaska and Hawaii were not affected.
The knock-on disruption will carry into Saturday. United Airlines planned to cancel most of its remaining flights on Friday night, Air Canada cancelled its remaining Friday flights between Canada and the US, and JetBlue said it expects delays to continue.
02. Outdated technology under scrutiny
Investigators will look at whether the failure is linked to the FAA’s nationwide rollout of a new artificial intelligence system to help identify problems and reroute planes, Mullin said. That system operates from one location near Washington, D.C., and only sends recommendations to air traffic control centres.
The government has been working to overhaul the outdated technology that air traffic controllers rely on since Congress approved $12.5 billion for the project last year. Miles of old copper wires have been replaced with fibre optic lines, and old radio systems are gradually being replaced at airports. But much work remains: Transportation Secretary Sean Duffy has said another $30 billion will be needed to finish the job, and the White House has begun lobbying Congress to approve it.
