Editor’s note: This story has been updated with additional information.

An FAA computer system used for communication with air traffic control and enabling pilots to access flight plans crashed early Wednesday morning, causing the FAA to ground all flights for a short time across the U.S., including North Carolina.

It is the first time that all flights have been grounded simultaneously since 9/11.

The system, known as the Notice to Air Missions system or NOTAM, failed around 4 am EST when passengers began to complain that their flights were grounded. 

 The FAA took action to ground all flights at 6:30 am and lifted the ban before 9 am.

About 4,500 flights were delayed, and 840 flights were canceled. The disruption may last into Thursday or longer.

According to their Twitter page, the Raleigh-Durham International Airport (RDU) expected “lingering effects on flights throughout the day. Travelers should still check with their airline before coming to the airport.”

“I guess it was a little unnerving at first, with everything that’s going on in our country and beyond, to have all flights halted by the FAA,” said Julie, a passenger at RDU, whose flight to Miami was delayed. Carolina Journal spoke with her by telephone as she was finally getting ready to board her plane around 9:30 am. “Supposedly, it was due to a system outage overnight that gives pilots their preflight check status. Anyway, they were able to restore it, and I am feeling much better now.”

Charlotte Douglas International Airport’s (CLT) Twitter page said much of the same. Flightaware.com, a website that tracks flights worldwide, showed a total of 339 flight delays at CLT as of 11 am, with 113 cancellations, 105 delays at RDU, and 16 cancellations.

A spokesperson for flyExclusive, one of the top five private aviation companies in the U.S., based in Kinston, N.C. said they are monitoring the effect of today’s FAA systems outage very closely and released the following statement: “The immediate operational impact on our flights has been abated with minimal delays today. However, we depend on commercial travel to move our pilots to planes. We are working to assess the full impact of the system failure on commercial travel so we can ensure minimal operational impact on our flights in both the near and long term.”

According to the FAA, a NOTAM is a notice containing information essential to personnel concerned with flight operations but not known far enough in advance to be publicized by other means. It states the abnormal status of a component of the National Airspace System (NAS) – not the normal status. It could range from things like potential icing to runway construction.

While an exact cause has yet to be determined, the Biden Administration claims it wasn’t a cyberattack.

The NOTAM system has been dubbed archaic by some in the industry, including fixingnotams.org, which cited a near disaster between three planes at the San Francisco International Airport in 2017 because of NOTAM.

“The NOTAM finding is emblematic of the increasing shortcomings of the system, developed in the 1930s and changed very little in most parts of the world since then, to convey critical information to pilots,” said the website in 2019. “In addition to archaic formatting issues, complicating interpretation and consuming time to translate, read and absorb, the system is overwhelmed with a proliferation of NOTAMs, which have increased from 500,000 in 2007 to 2 million and counting this year, worldwide.”

The website says the aviation industry has been trying to fix the NOTAM’s problem since 1964 with no real solution but some groups and companies have been working together since 2020 on the issue.

This has been the second in a series of interruptions and challenges for air travelers in a matter of weeks. Southwest Airlines continues to face scrutiny over canceling or delaying numerous flights over the Christmas holidays due to winter storms and archaic work scheduling systems for pilots and airline staff, leaving thousands stranded and having luggage gone missing.