I have a box full of these at home... They were indeed from control line airplanes... they were meant to run for about a minute then stop... the fuel tank is built into the backplate and mixture is controlled by the single needle... They were a ***** to start and were extremely noisy and dirty... I have fond memories of them growing up.. I even had one in a helicopter, which I still have... maybe 30 years old... probably still works... As far as hp... probably not mote than 1/10 hp...