FAA Ground Stop: Microsoft and SMART AI Vendor Both Deny Role

More than 3,220 flights into, within, or out of the US were canceled and roughly 10,200 delayed by 6:40 p.m. ET Friday, after the Federal Aviation Administration ordered every plane in American airspace grounded. The cause remains unknown — and the two companies most suspected of causing it say they had nothing to do with it.

Microsoft and Air Space Intelligence, the vendor behind the FAA's new AI-powered SMART system, both issued public denials on Friday. Their statements came hours after the FAA halted all flights nationwide over what it described as communications issues.

What did the vendors actually say?

Air Space Intelligence moved first. Online speculation had pointed at SMART, an AI tool that monitors air traffic and prevents delays, which began rolling out to wider use this week.

"The current ground stop is not based on or a result of the SMART system, any product of ASI or our integration with FAA and ATC," the company wrote on X.

Microsoft followed with its own denial. The software giant had a rough week already: a worldwide outage knocked out services like email for hours, snarling the workweek at major companies and inspiring memes from office workers. Some users wondered whether the two incidents were connected.

"We have no indication that the FAA's nationwide ground stop is related to any Microsoft services," the company wrote on X.

How bad was the disruption?

The scale is nearly unprecedented. The US has seen only one other nationwide ground stop since federal aviation officials famously froze American airspace during the 9/11 terrorist attacks.

According to FlightAware.com, the Friday stoppage had by evening produced:

• Over 3,220 canceled flights into, within, or out of the US
• Roughly 10,200 delayed flights
• Crowds at terminals nationwide as passengers were taken off planes

Photos from airports across the country showed crowds forming and planes lining up on the tarmac. Passengers waited inside the main terminal at Dulles International Airport in Virginia after the FAA acted on what it called extraordinary circumstances and reasons for safety, following an earlier report of serious air traffic control communications issues at the airport.

Is anyone taking the blame?

Not yet. At a press conference outside the White House on Friday evening, Department of Homeland Security Secretary Markwayne Mullin said authorities weren't ruling out any possible cause of the outage.

The SMART system drew suspicion partly because of its novelty. In September, POLITICO reported that airline industry veterans were initially nervous about the new system because of the FAA's vague description of what it would do. The tool rolled out to wider use only this week — days before the largest aviation disruption in a generation.

Both denials leave the investigation where Mullin put it: wide open. Until regulators identify the failure point, the airlines, the FAA, and two of the most-watched names in tech and aviation software will stay under the same cloud they just tried to clear.