Model aircraft have to be flown within visual line of sight (FAA Modernization and Reform Act of 2012, Section 336), which restricts the height.
Commercial use is already FAA territory and you have to be registered (Section 333 Exemption).
/Edit: Section 336, not 366.
But then if you look at this page[1] on the FAAs web site, it says only that operators are "strongly encouraged" to follow certain restrictions like line-of-sight operation. It doesn't say they have to.
Mind you, I follow all those rules myself when flying rc planes, and prefer that other in the hobby also do. I think they're good rules. I'm just playing with interpretation.
So if you exceed visual line of sight it becomes a normal aircraft, just like every other plane. And they all have to be registered.
However, I'm not certain that's the case.
I am.
> That would hold if we assume all things which fly (aside from animals, obviously) are under the jurisdiction of the FAA by default.
There's plenty of statute and precedent making it blindingly clear that this is the case.