A communications failure froze all US departures for more than 4 hours. Nearly 10,000 flights were cancelled or delayed.
WASHINGTON — On Friday, November 13, 20United States stopped flying.
The Federal Aviation Administration (FAA) issued a nationwide ground stop after a communications failure hit air traffic control centres across the country. It was the longest nationwide shutdown of flight departures since the September 11, 2001 attacks.
Transportation Secretary Sean Duffy said US airspace reopened at 8:15 p.m. Eastern Time, but warned that departures would resume gradually and it would take time for airlines to restore normal operations.
WHAT HAPPENED?
Duffy said the trouble began at 3:36 p.m., when air traffic control centres experienced instability in radar and communications systems.
The FAA ordered all departing flights across the country to remain grounded. Flights already in the air were allowed to land. At the time the ground stop was issued, 4,042 flights were airborne, destined for US airports.
The failure affected all 22 Air Route Traffic Control Centers that handle aircraft travelling between airports.
The outage appeared to be affecting a telecommunications network overseen by L3Harris Technologies, according to two airline officials.
HOW MANY FLIGHTS WERE AFFECTED?
By late Friday night, nearly 10,000 flights had been cancelled, including more than 2,200 each at Delta Air Lines and American Airlines, and 1,800 at United Airlines, according to Flightradar24.
Other trackers reported more than 4,700 flights cancelled and 10,000 delayed on Friday alone, with another 700 already cancelled for Saturday and 1,500 for Sunday.
Aviation analysts said the four-hour nationwide grounding could disrupt airline schedules for days.
For example, Singapore Airlines flight SQ23 from New York, originally scheduled to arrive at Changi Airport at 6 a.m. on November 14, was retimed to 6:48 p.m.
WAS IT A CYBERATTACK?
Homeland Security Secretary Markwayne Mullin said there was “zero evidence” so far that the outage resulted from a cyberattack or a rogue AI system, though investigators had not ruled out either possibility.
“There was no indication as of yet that this was a nefarious attack against us. It’s just a telecommunication outage as of right now,” Mullin told reporters outside the White House.
The National Security Agency was working with the Department of Homeland Security on the investigation.
Duffy said he and Mullin had met with President Donald Trump in the Oval Office to discuss the outage.
AN OLD SYSTEM UNDER STRAIN
The failure is the latest and most dramatic sign of strain on a US air traffic control system beset by aging technology, equipment and communications problems and a shortage of several thousand controllers.
Duffy blamed Congress for failing to fund a new system that he said could prevent such outages, and called for $50 billion to modernise it.
WHAT ABOUT PASSENGERS?
US airlines will not be required to provide compensation to stranded passengers because the carriers were not responsible for the FAA system failures.
THE LAST TIME THIS HAPPENED
The only other nationwide ground stop since the September 11 attacks came in January 2023, when the FAA halted domestic departures for around 90 minutes after a failure of its NOTAM system.
