Increasing the airspeed on a fixed-wing aircraft allows to reach higher load factors, sometimes beyond the structural strength. This is why some fixed-wing aircrafts have g-limitations.
Interesting. So are you saying that effectively a helicopter is always operating below Va, the speed where the wings (fixed wing) will stall before you can break anything?
Does that mean that if you try to pull cyclic hard enough to break things, the rotor blades will stall? That sounds fairly ugly since if they do, they will stall asymmetrically.
Re the Red Bull team... you can do just about any aerobatic manouver, except tumbles and outside loops, within an envelope of -1 to + 3. From that pov any Normal category fixed wing aircraft can be safely looped and rolled, you just have to be very good to not accidentally pull a bit harder. Bob Hoover used to demonstrate this. Given a G-meter and a parachute, I would be willing to loop or roll a 182, though not mine thank you very much. (And to be legal of course it would have to classified experimental). If an R44 is good for +3.5 then I guess you COULD loop it (not that I'm suggesting anyone should), though it's not something I'd care to try even WITH a G-meter and a parachute. You'd have to be super-careful on top, where normally you're pulling around +0.5 but it's VERY easy to float. Would be a lot of fun to try in a sim, if there was one.