The US Federal Aviation Administration (FAA) imposed a nationwide ground stop on Friday after a communications outage disrupted air traffic control centres across the country, forcing airlines to suspend departures and triggering widespread flight delays and cancellations.
The disruption affected all Air Route Traffic Control Centers, which guide aircraft at high altitudes. Transportation Secretary Sean Duffy said the FAA ordered departing flights to remain grounded while technicians investigated the problem. The agency initially said international arrivals and departures would be handled on a case-by-case basis.
The FAA described the incident as a temporary telecommunications outage. Air Current reported that the disruption involved air traffic control communication frequencies. Chicago O’Hare International Airport also implemented a ground stop because of the communications failure.
United Airlines said new domestic flights would not take off while the FAA order remained in effect. The disruption also affected international travel, with Air India warning that flights to and from the United States could face delays or other changes. The airline advised passengers to check their flight status before travelling.
FAA Reopens US Airspace After More Than Four Hours
The nationwide halt began shortly before 4 pm Eastern Time. Duffy announced that US airspace reopened at 8:15 pm ET, more than four hours after the ground stop was imposed. However, he warned that restoring normal operations would take time.
The outage caused significant disruption across the aviation network. More than 10,000 flights were affected, according to CNBC. FlightAware counted approximately 5,600 cancellations, with the number expected to rise as airlines adjusted their schedules.
Delta Air Lines and United Airlines said they were resuming operations after the restrictions were lifted. JetBlue Airways cancelled its remaining Friday flights and warned that disruptions could continue into Saturday. Airlines also cautioned that delays and cancellations could spill over into the weekend.
A European aviation safety organisation separately said that, at the FAA’s request and because of technical problems, flights departing from its member states for US airports would be suspended from 22:00 UTC on November 13 until 05:00 UTC on November 14.
Flight Disruptions Continue as Officials Warn Recovery Will Take Time
U.S. Transportation Secretary Sean Duffy said the nationwide flight groundings were caused by a telecommunications failure linked to aging network systems. He asked Congress for $50 billion in emergency funding to upgrade the air traffic control (ATC) system, clarifying that there was no widespread communications or radar outage during the incident. Homeland Security Secretary Markwayne Mullin said investigators have found no evidence of a cyberattack, AI interference or any link to Microsoft’s recent service outage. He warned that aging infrastructure and data overload pose a national security risk, with investigations and remedial work still underway.
More than 700 flights to and from the United States were canceled on Saturday, according to FlightAware. As of 7:45 p.m. ET, Delta had canceled around 5% of its flights, United 4% and American 2%. Airlines noted that cancellations can also be preemptive and may result from weather, maintenance or crew-scheduling issues.
Mullin said officials have not set a timeline for ending the nationwide grounding, warning that the disruption would take time to resolve and that flight operations would not return to normal within an hour.
FBI Rules Out Cyberattack as Investigators Examine Technical Failure
The FBI found no indication that the communications disruption was caused by a cyberattack or criminal activity, Bloomberg reported, citing an informed source. Investigators were examining whether a software update may have triggered the outage.
Homeland Security Secretary Markwayne Mullin also said there was no indication of anything suspicious at that stage. Microsoft separately stated that it had seen no evidence connecting the FAA ground stop to any Microsoft service.
The incident renewed concerns about the condition of America’s air traffic control infrastructure. Officials cited overloaded and outdated systems as possible factors behind the disruption, according to the Associated Press.
The timing also drew attention because the White House had asked Congress for an additional $30.1 billion to modernise aviation infrastructure only hours before the outage, according to AeroTime.
The FAA’s nationwide ground stop was lifted, but the scale of the disruption highlighted the vulnerability of the US aviation network to failures in critical communications systems. Investigators are continuing to examine the cause of the outage.
Why did the FAA impose a nationwide ground stop?
The FAA imposed the ground stop after a communications outage affected all Air Route Traffic Control Centers in the United States, disrupting the systems used to guide aircraft.
When did the FAA lift the ground stop?
US airspace reopened at 8:15 pm Eastern Time on Friday, more than four hours after the nationwide halt began.
How many flights were affected by the FAA outage?
More than 10,000 flights were disrupted, according to CNBC. FlightAware reported approximately 5,600 cancellations, with the total expected to increase.
Was the FAA communications outage caused by a cyberattack?
The FBI found no initial indication of a cyberattack or criminal act. Investigators were examining whether a software update may have triggered the disruption.
Were flights between India and the United States affected?
Air India warned that its flights to and from the United States could face disruptions and advised passengers to check their flight status.
Will flight delays continue after the ground stop was lifted?
Yes. Airlines warned that cancellations and delays could continue into the weekend as they worked to restore normal schedules.
