Parent's comment is a little overblown, there are plenty of people in the US who build all sorts of things just like this and have no trouble(helps to be away from populated areas). Regulations aren't necessarily a bad thing. For example, I'd hate to be in the crowd of onlooker when something explodes/comes flying off, or to have my property crashed into by a DIY helicopter or some-such. Note the kids just feet away from the rotor assembly in picture #37.
