High acquisition cost, high metallic content, high weight, and high cost of installation characterize the present state-of-the-art in waterjet drives above 150HP. This work addresses all of these problems through the use of high-strength composite materials and integration of the jet drive intake duct into the hull of the vessel at the time of hull fabrication. Novel mechanical configuration of drive components removes the high stresses normal in conventional drive intake ducts, allowing a composite intake to be integrated into a composite hull at low cost. Collateral advantages of this novel approach are a reduction in the number of components and in total drive unit weight. Additionally, it allows the placement of the engine closer to the transom with no compromise to the intake performance. Work includes hydrodynamic optimization of the intake shape to assure performance superior to comparable metallic jet drives. A prototype unit based on the novel design is constructed, installed and tested, and measured data are used to predict the performance of an 11 meter RIB with two such drives installed. Some drive components, in addition to the intake, are also made of composite materials, leading in the future to a truly all-composite waterjet propulsion system.
Keywords: Composite Waterjet, Light Weight Waterjet, Jet Drive, Marine Propulsion, Waterjet Propulsion
