The Federal Aviation Administration ordered departing flights across the United States to remain on the ground Friday, Nov. 13, after a communications problem affected air traffic control operations.
The FAA said the ground stop was imposed for safety reasons and would remain in effect until further notice. The agency did not provide a nationwide timetable for resuming departures in its initial advisory. Transportation Secretary Sean Duffy said the communications issue affected Air Route Traffic Control Centers, which coordinate aircraft traveling between airports. FAA technicians were investigating the problem.
The agency described the incident as a temporary telecommunications outage. It said international flights approaching the United States would be handled individually and that aircraft already in the air had been accounted for. Officials had not publicly identified the specific equipment or systems involved.
The disruption prompted delays and cancellations as airlines paused departures and assessed their schedules. The number of affected flights was not confirmed in the FAA’s initial advisory. Officials said airlines could submit flight plans within a four-hour window as the agency managed the situation.
Homeland Security Secretary Markwayne Mullin said there was no indication at that point that the outage was a deliberate attack. He added that authorities were not ruling out possible causes. Preliminary reports cited by news organizations also indicated that investigators had not found evidence of a cyberattack. Officials had not released a final determination.
Mullin said there was no reason for the public to fear for loved ones and said the incident was not another Sept. 11 attack. President Donald Trump had been briefed, according to reports. The White House had not announced evidence linking the communications failure to a hostile act.
The FAA advisory listed the nationwide ground stop alongside other operational constraints, including weather-related conditions and delays at individual airports. The agency did not say whether those separate issues contributed to the nationwide order. It instructed departing traffic to remain on the ground pending further notice.
The previous nationwide ground stop occurred in January 2023, when a failure in the FAA’s Notice to Air Missions system disrupted flight operations. Before that, U.S. airspace was closed following the Sept. 11, 2001, terrorist attacks. The circumstances differ: the 2023 disruption involved an aviation information system, while the 2001 shutdown followed terrorist attacks.
The outage comes as the FAA continues a multiyear effort to modernize air traffic control infrastructure, including communications equipment and other systems. The agency has reported progress in replacing older equipment, but has not said whether aging technology contributed to Friday’s incident. No connection between the modernization program and the outage had been established.
The FAA had not released a detailed account of which communications systems failed, how many control facilities were affected or whether backup systems were used. Those details will help determine how the disruption spread and whether additional safeguards are needed.
Airlines and passengers faced uncertainty over departure times as technicians investigated and officials assessed when flights could resume. Travelers were advised to check directly with their airlines for flight-specific updates. At the time of the initial announcements, authorities had not provided a confirmed restoration time or identified a cause beyond the reported communications outage.
