FAA Lifts Nationwide Ground Stop After Communications Failure

The Federal Aviation Administration lifted a nationwide ground stop on flights at 8:15 p.m. Eastern on November 13, after a communications and data problem disrupted air traffic operations for more than four hours. Transportation Secretary Sean Duffy said flights would resume gradually as airlines and officials worked through the backlog.

Duffy attributed the shutdown to overloaded legacy switches and routers that produced inconsistent data across the air traffic control network. He said radar and communications had become unstable at facilities across the country, prompting the FAA to stop departures as a precaution. The cause remains under investigation.

More than 3,500 aircraft were airborne when the stop began, Duffy said. He said pilots and air traffic controllers followed established procedures to land them safely. An FAA timeline described exceptions for critical medical evacuation, lifesaving cargo and law-enforcement flights during the stop.

Homeland Security Secretary Markwayne Mullin said officials had seen no evidence of a cyberattack, but were continuing to investigate and would not rule out that possibility. He also said the disruption was not connected to Microsoft...