[jdubner]

This is not true. ADS-B OUT is required to fly in certain classes of airspace, above 10,000 feet, etc. -- anywhere a transponder is currently required. That's all.

That leaves a lot of airspace in the US. Someone flying his C182 in eastern Wyoming may not bother with it as he does not see any benefit. Here in western Oregon, I see the benefit (weather and traffic via ADS-B IN) and have equipped my aircraft even though I (mostly) avoid the airspace where it is required.

[plugger]

Thanks for the info. I had read it was becoming mandatory in the US in 2020. That was in the context of Australian regulations where aircraft still aren't forced to have ADS-B.