NEW YORK (1010 WINS/WCBS 880) -- The Federal Aviation Administration lifted a nationwide ground stop Wednesday morning after a major system outage halted departures at airports and caused cascading delays and cancelations.
“Normal air traffic operations are resuming gradually across the U.S. 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 FAA tweeted just before 9 a.m. “We continue to look into the cause of the initial problem.”
Delays and cancelations continued into Wednesday even after the 90-minute ground stop was lifted, with the delays concentrated on the East Coast and expanding westward.
There were more than 4,500 delays and 800 cancelations nationwide as of 10 a.m., according to FlightAware. JFK, Newark and LaGuardia airports were each experiencing hundreds of flight delays.
The FAA had ordered airlines to “pause” departure flights nationwide at 7:30 a.m. after its Notice to Air Missions (NOTAM) system “failed.”
The system informs pilots about critical information, including airspace closures and hazards like severe weather, bird strikes and broken equipment. The cause of the failure is unknown.
“The United States NOTAM system failed,” the FAA said in an advisory early Wednesday, hours before the ground stop was ordered. “Technicians are working to restore the system...”
“Operations across the National Airspace System are affected,” the agency said at the time.
White House press secretary Karine Jean-Pierre said President Joe Biden had been briefed by Secretary of Transportation Pete Buttigieg on the outage and ordered the Department of Transportation to investigate why the system went down.
“There is no evidence of a cyberattack at this point, but the President directed DOT to conduct a full investigation into the causes,” Jean-Pierre tweeted.
“I just spoke with Buttigieg,” Biden told reporters a short time later outside the White House. “They don't know what the cause is. [...] I told them to report directly to me when they find out.”
All aircraft are required to route through the NOTAM system, including commercial and military flights, causing the widespread disruptions.
According FAA advisories, the NOTAM system failed at 8:28 p.m. Eastern on Tuesday preventing new or amended notices from being distributed to pilots. The FAA resorted to a telephone hotline in an effort to keep departures flying overnight, but as daytime traffic picked up it overwhelmed the telephone backup system.
Some medical flights could get clearance, while Air Force spokeswoman Ann Stefanek said U.S. military flights were not impacted because the military has its own NOTAMS system separate from the FAA system and the military’s system was not affected by the outage.
The Associated Press contributed to this report.