RST Engineering wrote:
Does anybody know if federal case law exists challenging state registration
of what the federal government already registers?

Jim

I'm probably remembering this incorrectly, but there was a time in
Massachusets or a state up there, where the state wanted to issue state
pilot certificates to pilots. The FAA was not too happy about that, and
it never materialized. I can't remember the state or date...my aviation
law class was a verrry long time ago.