The Federal Aviation Administration stopped departing flights at all US airports on Friday, November 13, Transportation Secretary Sean Duffy said at 4:16 p.m. ET. The FAA blamed a temporary telecommunications outage. As of 6:15 p.m. ET, neither the FAA nor Duffy had said the stop was over. An FAA advisory estimated an 11 p.m. ET end, News9 in Oklahoma City reported.
Which flights the FAA stopped
Every departing flight at US airports had to stay on the ground. Flights need approval from the FAA office that ordered the stop before they can depart.
Duffy announced the ground stop for all US airports in a post on X. Under FAA rules, a ground stop requires the affected planes to stay on the ground. They cannot be released without the approval of the FAA office that ordered it.
The agency acted "due to extraordinary circumstances and for reasons of safety," CBS News reported on Friday. In its own post on X at 5:02 p.m. ET, the FAA said all flights had been halted. It said every flight had been accounted for. It added that international flights would be handled case by case. The command center's notice, quoted by CBS News, applied this to international flights arriving in the US.
What caused the FAA ground stop
Officials blamed a telecommunications outage at the centers that guide planes between airports. No official had named the system that failed.
Duffy said the stop followed "a communication issue impacting all Air Route Traffic Control Centers." These are the FAA facilities that guide planes mainly while they travel between airports. He said FAA technicians were investigating.
In its 5:02 p.m. post, the FAA called the problem "a temporary telecommunications outage." Neither the FAA nor Duffy named the system that failed.
Homeland Security Secretary Markwayne Mullin told reporters at the White House there was "no indication as of yet that this was a nefarious attack against us," CNN reported. He said officials were not ruling out any cause. He also said the outage was not connected to the Microsoft outage of Thursday, November 12.
Mullin said officials were looking at whether the FAA's new AI-supported air traffic system played a part, CNN reported. ASI, the company that built that system, said on X that the stop was not a result of its product. Mullin also said planes in the air could still be reached, though not with full clarity, because most communications have backups, NBC News reported.
Whether the FAA ground stop has been lifted
No lift had been announced by 6:15 p.m. ET. An FAA advisory gave 11 p.m. ET as an estimated end, News9 reported.
The FAA's newest post on X was still the one from 5:02 p.m. ET, and Duffy had posted nothing on the stop since 4:16 p.m. ET.
The FAA's estimate of an end time came in an advisory from its Air Traffic Control System Command Center. The advisory says the stop took effect at 3:54 p.m. ET, News9 reported. The command center also said "all departing traffic should remain ground stopped until further notice," CBS News reported.
How many US flights were delayed or canceled on the day of the FAA ground stop
A flight tracker counted more than 9,900 US delays and more than 1,000 cancellations on Friday by early evening. Some had other causes, such as wind.
By 5:35 p.m. ET, flight tracker FlightAware had counted more than 9,900 delayed flights within, into or out of the United States on Friday. It had counted more than 1,000 cancellations, up from 601 at 5:15 p.m. ET. Those totals cover the whole day. They also include delays from other causes, such as wind at San Francisco and New York's LaGuardia, which the FAA's status page listed.
The FAA's airspace status page also showed delays at single airports. At 6:16 p.m. ET, its feed listed departure delays of up to 3 hours 15 minutes at Chicago O'Hare, which it put down to FAA equipment. The same feed did not list the national stop among its ground stop programs.
Airline waivers after the FAA ground stop
United lets affected travelers rebook for free on its flights through November 20. American and Southwest had posted no notice by 6:15 p.m. ET.
United Airlines posted a travel waiver for a nationwide air traffic control outage on its travel alerts page. It covers tickets bought on or before November 12 for travel on November 13 or 14. Those travelers can move to another United flight departing between November 12 and November 20. United waives the change fee and any fare difference. The new ticket must be in the same cabin and between the same cities.
At about 6:15 p.m. ET, the travel alert pages of American Airlines and Southwest Airlines showed no notice about the ground stop. American said in a statement that it would get customers on their way as soon as possible once the FAA lifts the stop, CNN reported.
How airline shares traded on the day of the FAA ground stop
Around 5:48 p.m. ET, StockTitan's real-time Nasdaq data showed American, United and Delta below their Friday closing prices. Southwest had traded as much as 2.0% under its close.
Shares of four large US airlines traded lower after the stock market closed at 4 p.m. ET on Friday. The ground stop took effect at 3:54 p.m. ET, six minutes before the close, according to the advisory News9 reported. None of the airline or official statements cited here gave a reason for the share moves.
Around 5:48 p.m. ET, American Airlines (AAL), United Airlines (UAL) and Delta Air Lines (DAL) were down 1.4% to 2.1% from their closing prices, StockTitan's real-time Nasdaq data shows. Southwest Airlines (LUV) traded as low as $44.03 between the 4 p.m. close and 5:48 p.m. ET, 2.0% under its closing price.
Past nationwide FAA ground stops
CNBC reported that the last nationwide stop came in January 2023, after an FAA system that sends safety notices to pilots failed. The FAA lifted it the same morning.
The last nationwide ground stop came in January 2023, CNBC reported. It followed an overnight outage of the FAA's Notice to Air Missions system, which gives safety information to flight crews. At 7:15 a.m. ET on January 11, 2023, the FAA said it had ordered airlines to pause all domestic departures, according to its statements. At 8:50 a.m. ET, it said the ground stop had been lifted.
A preliminary FAA review traced that outage to contract workers. They deleted files by mistake while trying to keep a main database and its backup in step, the FAA said. It found no evidence of a cyberattack. Before 2023, flights were last halted nationwide after the September 11, 2001, attacks, CNBC reported.
What to watch
- When departures resume: the FAA's posts on X and its airspace status page.
- What failed: an FAA or Transportation Department statement naming the system. Mullin said officials were looking at the FAA's new AI-supported system.
- More airline waivers: the travel alert pages of American, Delta and Southwest.
Our numbers
These figures are our calculations from StockTitan's real-time Nasdaq data, measured from each stock's final price of the regular session in StockTitan's daily price records. Far fewer shares trade after the close than during the day, so these prices can change quickly.
- American down 2.1%: $12.90 at 5:48 p.m. ET against its $13.17 close
- United down 1.6%: $107.60 at 5:47 p.m. ET against its $109.31 close
- Delta down 1.4%: $85.00 at 5:48 p.m. ET against its $86.25 close
- Southwest down 2.0% at its low: $44.03 between the 4 p.m. close and 5:48 p.m. ET, against its $44.94 close
Frequently asked questions
As of 6:15 p.m. ET on Friday, November 13, neither the FAA nor Transportation Secretary Sean Duffy had announced that it was lifted. An FAA advisory gave 11 p.m. ET as an estimated end, News9 reported.
The FAA blamed "a temporary telecommunications outage" in a post on X. Duffy said a communication issue hit all of the centers that guide planes between airports.
Homeland Security Secretary Markwayne Mullin said there was no indication as of yet of an attack, CNN reported. He said officials were not ruling out any cause.
United's waiver covers tickets bought on or before November 12 for travel on November 13 or 14. It allows a new United flight departing by November 20, in the same cabin and between the same cities, with no change fee or fare difference.
CNBC reported that the last one came in January 2023, after an outage of the FAA's Notice to Air Missions system. The FAA said on January 11, 2023, at 8:50 a.m. ET that the ground stop had been lifted.