Donut King,
Are you thinking of the Piasecki 16H Pathfinder?
That was a compound helicopter, a 5 seater with a 3 bladed main rotor. It had a wing mounted beneath the fuselage and a ducted airscrew in the tail, with vertical vanes to deflect the efflux laterally to counteract torque reaction.
It was flying at up to 170mph in the early 1960s, powered by a 510 hp Pratt & Whitney PT6B-2. There was a proposed twin engined version but I'm afraid my spotter's knowledge finishes here!
I would be interested to hear how this "new" (it's been considered before) design of aircraft gets over the age-old problems of excessive retreating blade stall and advancing blade compressibility at the proposed high speed of 350 kts......
