two engines but one pilot and one tail rotor, Hmm....
UKCAA, bless 'em: proposed twin engines thro' single gearbox and prop aeroplanes banned because failure of the single drive system ie prop, would lead to a forced landing. Same logic clearly doesn't apply to flying machines with a big propeller (one) on the top ( not to mention the stern propeller,eh?)
Anyway, 2nd engine is for girls.