Have you watch one of those things fly? I have a DVD with pros. flying them things in a contest. I think 3D is when the will do really neat things wile flying kind of in place. The will appear to just float in the air wile doing flips and stuff. I am not really sure, but I think it's something like that. I know 3D air planes fly almost in place and can hover like a coptor. They will almost stand straight up on the prop.