The US Federal Aviation Administration (FAA) ordered a nationwide ground stop on November 13, 2026, “due to extraordinary circumstances and for reasons of safety”. This marks only the third time this century that the FAA has issued such an order, following September 11, 2001, and January 11, 2023, when a NOTAM system failure disrupted operations.

US Secretary of Transportation Sean Duffy said the ground stop was prompted by “a communication issue impacting all Air Route Traffic Control Centres”, adding that FAA technicians were investigating the cause. The disruption also came a day after a global Microsoft Office outage started.

Earlier in 2026, the FAA announced it was developing an artificial intelligence-based programme, to be launched before year-end, to analyse airline schedules, weather conditions, airport capacity, and airspace constraints to forecast traffic flows and identify potential conflicts before departure.

However, there is no indication that the communications failure was linked to the AI initiative or the Microsoft outage.