The ubiquitous Bell 47 gets dubbed in everywhere, whether it's a death banana or a Jetranger. I guess it's the sound JoePublic expects a helicopter to make. I love the way the throttle is always chopped on the soundtrack with the aircraft in a 10 foot hover. Artistic licence? The worst case I ever came across with regard to technical inacurracy was when Wilbur Smith's hero in 'Hungry as the Sea' went and "stood between the pilots as CapeTown came into view".
Good trick in a S58T!