My (armchair) understanding is this isn't where you "can" and "cannot" fly - it should be viewed more as "where you don't need permission", and "where you do ne

My (armchair) understanding is this isn't where you "can" and "cannot" fly - it should be viewed more as "where you don't need permission", and "where you do need permission". The later does not mean permission cannot be obtained, only that it is required.