FAA blames a contractor's wiring job, not hackers, for Friday's nationwide ground stop

The FAA held every departing flight in the country at about 4 p.m. Eastern on Friday after its telecommunications started failing at facilities across the country. More than 3,500 planes were in the air when it began. Medevac, critical cargo and law enforcement flights were allowed to keep flying. Transportation Secretary Sean Duffy said the stop was lifted around 8:15 p.m.

At a Saturday news conference, FAA Administrator Bryan Bedford said the agency had found the fault and saw "zero evidence of anything nefarious." Duffy said a contractor for L3Harris, the FAA's telecom provider, was moving lines from old copper wire to fiber at a remote FAA site. Investigators are still working out whether a bad router or bad work caused it. Homeland Security Secretary Markwayne Mullin said there was no sign of a cyberattack or a terror plot.

FlightAware counted more than 4,000 canceled flights and more than 13,000 delays by Saturday, and the aviation data firm Cirium put the number of stranded passengers at about 1.5 million. Atlanta, Chicago O'Hare, Houston Bush, LaGuardia and Dallas-Fort Worth were hit hardest. The FAA says airlines expect to be back to normal by the end of Sunday.

The last nationwide stop was in January 2023, when the FAA's pilot notice system failed. Before that, the only full nationwide stop came after the September 11 attacks. Duffy is asking Congress for $50 billion to replace the system and warned that more disruptions are likely without it.