dude, that's a badass pilot!

helicopters aren't capable of flips

Unless I actually see that happen, I don't believe that it did. The propellors push air downward which is what keeps it up in the air. A helicoptor being upside down like that would be pushing the air upward and itself downward along with the help of gravity. Physics sucks!!! +3

these Propllors can be switched to push the air up and down its called an idle switch
E.G

I've seen it a RAF Waddington air show!
Here you see a Lynx Helicopter doing them!

nice! sick pilot! +3

Sickness