FAA ground stop: Here’s why sources say it happened, according to reports

Sources say that Friday's nationwide ground stop, which resulted in massive delays for thousands of flights and nearly all domestic travelers, was caused by a communication system reboot, CBS News reports.

According to multiple sources with knowledge of the incident, an update to a private communications network used by air traffic controllers forced the system to reboot and impede communications at the nation's 22 regional air traffic control centers, CBS News reported.

The Federal Aviation Administration (FAA) has not yet provided details on the cause and the ground stop remains in place as of publishing.

As recently as 6 p.m. ET, insiders reported the FAA was still investigating the circumstances behind the communication blackout.

Following confirmation of a telecommunications outage, social media users theorized the blackout may have been a consequence of the FAA's new AI-powered air traffic control system, known as Strategic Management of Airspace, Routes and Trajectories, or SMART. Others suggested the recent Microsoft outage could have been a factor.

When asked if AI played a role in the ground stop, Homeland Security Secretary Markwayne Mullin told the press that officials couldn't "rule anything out."

Air Space Intelligence (ASI), the company behind SMART, denied claims the new AI tool was involved in the ground stop. Microsoft also issued a statement, writing: "We have no indication that the FAA’s nationwide ground stop is related to any Microsoft services."

The FAA has undertaken an administration-wide modernization project, including phasing out the use of floppy disks for storing weather conditions, airport status updates, equipment issues, and other critical information.