| I agree, if I take a picture with my camera, it does not automatically | mean that no one can use it without my permission and that it is | protected by law. Kind of like patent law, you have to do something to | protect it from free use or theft of an idea.
[ Note: Everything I say here is specific to the US. ]
Um, you're confusing patents with trademarks. Trademarks are what need to be protected, not patents, and not copyrights.
| If you copy a trim scheme from a full size aircraft to your model, | are you going to jail? Don`t think so, and do copywrights expire | like patents?
Yes, copyrights do eventually expire, unless you're Disney and can keep buying extensions from Congress.
In any event, copyright infringement is usually a civil matter, not a criminal one. So you get sued rather than going to jail.
| Like old software that eventually becomes public domain.
The only computer software that I can see that would have become public domain because it's copyright has expired would be that which was published before _1963_ and the copyright was not renewed. Yes, all computer software should eventually enter the public domain, but it's going to be a while.
If you're wondering about copyright durations in the US --
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If you're wondering about the various forms of intellectual property protections in the US --
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Please, if you can't at least skim over all the information out there on IP law, don't try to pass yourself off as an expert. IP law is complicated, and not always related to common sense.
(And no, I'm not a lawyer.)
| Look at the model kit makers.. how many Ugly Stick designs were | really just slight mods of Phil Krafts original... MW sweet stick?
On some level, all planes are slight mods on some other plane out there ...
In any event, it looks like a `Design Patent' (look at the second link I gave you) could cover a specific type of model airplane, say the Ugly Stick. However, getting a patent is expensive -- how many model airplanes have been patented? I doubt the number is very high, at least not until you start getting into the commercial/military UAV area. And even if the Ugly Stick had been patented, it would have expired by now (only being valid for 14 years.)