FAA says system restored after more than 4,300 flights grounded due to technical snag

The Federal Aviation Administration on Wednesday announced that its NOTAM (Notice to Air Missions) system— which alerts pilots and crew to advisories and information for flights— has been fully restored and the ground stop has been lifted, hours after it experienced a major technical glitch.

“Normal air traffic operations are resuming gradually across the US following an overnight outage to the Notice to Air Missions system that provides safety info to flight crews. The ground stop has been lifted,” the agency tweeted. 

The agency hasn't provided any information as to what caused the outage to occur. “We continue to look into the cause of the initial problem,” the tweet said. 

More than 4,300 flights came to a grinding halt on Wednesday after the Federal Aviation Administration (FAA)— which alerts pilots and other flight personnel about hazards or any changes—experienced a major computer outage.

In an advisory issued in the morning, FAA said that it's NOTAM (Notice to Air Missions) system that alerts pilots and crew to advisories and information for flights had "failed" and it could not give a timeline as to when it would be back.

More than 3,700 flights within, to and out of the U.S. were delayed as of around 8:30 a.m. Wednesday, according to the online flight tracker FlightAware. Nearly 560 flights were listed as cancelled. The FAA then ordered airlines to pause all US Departures until 9 a.m. EST.

The White House denied it as a case of a cyberattack, but President Joe Biden directed the Department of Transportation to investigate the cause of the disruption.

Biden said that he was briefed by Transportation Secretary Pete Buttigieg, who told him they still had not identified what went wrong.

“I just spoke to Buttigieg. They don’t know what the cause is. But I was on the phone with him about 10 minutes,” Biden said. “I told him to report directly to me when they find out. Air traffic can still land safely, just not take off right now. We don’t know what the cause of it is.”

Buttigieg said in a tweet that he is in touch with the FAA and monitoring the situation.

The outage comes due to failure of the Notice to Air Missions (NOTAM) system that alerts pilots and other personnel about airborne issues and delays at airports across the country.

"The FAA is still working to fully restore the Notice to Air Missions system following an outage. While some functions are beginning to come back on line, National Airspace System operations remain limited," the FAA said in another tweet.

"Technicians are currently working to restore the system," the website showed.

FAA told NBC News that it was working to restore the NOTAM system. 

"Operations across the National Airspace System are affected," the FAA said.

"The FAA is working to restore its Notice to Air Missions System. We are performing final validation checks and repopulating the system now. We will provide frequent updates as we make progress," it said. 

(With inputs from agencies)

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