Hundreds of US flights are grounded leaving passengers stranded after an FAA systems outage

The US Federal Aviation Administration (FAA) system that alerts pilots and other flight personnel about hazards or any changes to airport facility services and relevant procedures was not processing up-to-date information, showed the website of the civil aviation regulator on Wednesday.

In an advisory, the FAA said its NOTAM (Notice to Air Missions) system had “failed.” There was no immediate estimate of when it would return, the website showed, although NOTAMs issued before the outage could still be seen.

More than 400 flights were delayed in, to or out of the United States as of Wednesday at 5:31 a.m. ET, flight tracking website FlightAware showed. It was not immediately clear if the outage was a factor.

“Technicians are currently working to restore the system,” the website showed. The FAA was not immediately available for further comment.

A NOTAM is a notice that contains essential information for personnel related to flight operations, but which is not known sufficiently in advance to be published by other means.

The information can be up to 200 pages long for long-haul international flights and can include items such as runway closures, general bird warnings, or low-altitude construction obstacles.

Federal officials said Tuesday they will require charter airlines, air travel operators and plane manufacturers to develop detailed systems to identify potential safety issues before accidents happen.

The Federal Aviation Administration said safety management systems have made travel on large airlines safer since their adoption was required in 2018.

“Expanding safety management systems to other aviation industry players will reduce accidents and incidents and save lives,” Acting FAA Administrator Billy Nolen said in a statement.

The National Transportation Safety Board, which investigates accidents, has pushed for wider adoption of such systems.

In 2020, Congress directed the FAA to require them from aircraft manufacturers after two fatal crashes involving Boeing 737 Max planes. The FAA said its proposal on Tuesday went further by including smaller passenger transport operators.

To justify expanding the requirement to smaller airline operators, the FAA cited incidents including a 2015 seaplane crash near Ketchikan, Alaska, that killed the pilot and eight passengers.

The NTSB blamed pilot error and the company’s lack of a formal safety program.

The FAA said Tuesday that if the proposed rule had been in effect, the company would have taken steps that could have prevented the accident, including having a manager responsible for assessing the safety risk.

The FAA has an explainer about safety management systems, which have been a growing trend in aviation in recent years.