Radio is not a nationwide _system_ that can go down. ATC just uses basic AM radio for radio comms.

Yesterday I was flying out of lovefield in Dallas and the radios went down. We were stuck for about 10min only thankfully.

Radar multiplexer pipeline, or some component of it, is likely down.

https://www.sunhillo.com/wp-content/uploads/2025/04/SUN3125-... (page 3, bottom graphic)

(all the radars --> multiplexer [sadness here] --> radar data consumers)

What backup systems exist for air-to-ground communication? Something satellite based?

Does ATC run on Microsoft 365?

I'm wondering if this is another case of delayed Y2K, where the system suddenly thinks the century part is 19 instead of 20 for a two digit year of 26.