Graupner,Hydro-Antrieb II,1782

Hydro-Antrieb II Graupner 1782 Completely assembled. The unit is designed to handle electric motors or combustion engines having an output of up to 1 kW. Equipped with a hi-performance marine propeller of the new series this unit can be operated with the prop semi-submerged as well as fully submerged. When the boat is travelling at high speed its deflection angle must not exceed 20º. The inclination of the prop shaft may be altered and the thrustangle adapted for optimum planing attitude of the boat and maximum speed. Dimensions (nom.) Length 100 mm, height 112 mm, M4 shaft thread

This novel propulsion system is used to drive and steer boats of the hydroplane type. Thrust is provided by a HYDRO surface-propeller which operates semi-submerged in the water, when the boat is planing. Semi-submerged propellers are mainly used on fast racers. In the case of model boating they are tethered-running NAVIGA A class racers, HYDRO racing boats and catamarans. The blades of the semi-submerged propeller, immersed at one time of a revolution, above the water in the next one, throw up a most impressive plume of spray water behind the boat, sure sign of optimum propeller efficiency.