Not quite all aircraft are required to have ADS-B in all situations, there are a number of edge cases out there. But close enough, I suppose, and most planes people would want to track are required to have it.
However, there's also a new privacy initiative that allows aircraft to fly under temporary ids. The FAA will still know who they are, but for 3rd parties it will become much more difficult to determine.
However, there's also a new privacy initiative that allows aircraft to fly under temporary ids. The FAA will still know who they are, but for 3rd parties it will become much more difficult to determine.
https://www.aopa.org/news-and-media/all-news/2019/december/2...