I myself took a shot at building one a few years ago.

It is a twin-engined HH-1N, a model that until recently was used by the US Navy for Search-And-Rescue missions. I was (and still am) quite happy with how it turned out, but one of the things that I never liked was how the sliding doors on the cabin don't follow the contours of the fuselage when open. Looking at my pictures right now, I find none that illustrate this clearly. This is probably no coincidence!
This week the ever-innovative Mike Psiaki posted pictures of his own new model of a Huey. His older model was already more than decent, but the new one tops it. It's full of great techniques, it's small enough to look good with minifigs and he's come up with a pretty radical way to make the doors work, solving the problem I couldn't a few years ago.

I don't normally say this sort of thing, but this has to be the best LEGO Huey model ever. Great work.