Was Microsoft behind US flight chaos? Company responds after FAA ground stop disrupts over 16,000 flights

Microsoft on Friday (Nov 14) said that the air traffic control failure in the US that grounded all departing flights was not linked to its own global outage. This comes after the US Federal Aviation Administration (FAA) issued a national ground stop “due to extraordinary circumstances and reasons for safety.” According to flight tracker FlightAware, more than 10,000 flights were delayed, and over 6,600 were cancelled.

“We have no indication that the FAA’s nationwide ground stop is related to any Microsoft services,” Microsoft said in a statement on X.

Microsoft and FAA outages ‘separate issues’

Microsoft 365 suffered a major nationwide outage starting Thursday (Nov 13). Several of its services, including Outlook, Teams, Copilot and Xbox Live, were down for users in 74 countries. After over 30 hours of Microsoft 365 disruptions, the company said in an update, “We have completed our efforts to address the underlying issue of the incident and restored service to the remaining impacted customers and regions.”

Shortly before 4 pm ET on Friday (Nov 14), the FAA suffered a telecommunications outage. The two massive outages at the same time made people online try to connect them. However, Homeland Security Secretary Markwayne Mullin said that the two were “separate issues”, adding that he did not see “any reason to connect those two at all.”

What caused FAA ground stop?

Transportation Secretary Sean Duffy said that the FAA’s disruption was caused by its ageing network.

“Our switches, our routers actually got overloaded with data,” he said at a White House briefing, describing a system that still runs on “1980s little copper lines.”

The unexpected ground stop left around 1.5 million people stranded. Mulling said that there was “zero evidence” to suggest that the disruption was caused by a cyberattack. When asked whether AI had anything to do with it, he replied, “we call it SI around here,” using the administration’s preferred term for artificial intelligence.

The FAA had activated SMART, an AI-based traffic planning tool developed by Air Space Intelligence, at all 22 centres just three days before the disruption. However, the company clarified on X that the ground stop “is not based on or a result of the SMART system.” Duffy dismissed any link, saying, “This is not even plugged in.”

An update to its L3Harris-managed telecom network reportedly triggered a system crash at the FAA. Duffy is seeking $50 billion from Congress to overhaul air traffic control, warning that failures will continue without upgrades.

Meanwhile, Microsoft has blamed its disruption on a flaw exposed by a recent network update, with estimated productivity losses nearing $7 billion.