In the big FAA NOTAM system outage in January 2023, nearly all major U.S. airports were affected because the system that sends safety notices to pilots went down. That triggered a rare nationwide ground stop, disrupting more than 11,000 flights and causing delays and cancellations at hubs like JFK, LaGuardia, Newark, Atlanta, Dallas–Fort Worth, and many others across the country.
In newer outages or partial system issues, the FAA typically lists affected airports on its National Airspace System pages and coordinates with airlines. If your route involves big hubs, assume knock-on delays are possible even if your airport isn’t on the original list. During any outage, airport services and airline travel services can help you reroute, arrange hotel or meal support (where policies allow), and protect your onward connections.
Detailed explainer of the US NOTAM disruption and which airports were hit