Helicopter

Since a wonderful commenter wanted me to post about my air hogs helicopter, I guess I will.

So when the propellers spin, air comes at it and splits, the top of the propeller is bent so air has to move faster on the top to meet at the other end, that causes low pressure. That makes the helicopter move up. To move up faster the helicopter tilts it's wings more to cause lower pressure and so the helicopter takes that space faster.