Water-jet propulsion unit for vessels

摘要

Water-jet propulsion unit for vessels which includes a water duct having an inlet and outlet portions and an impeller disposed in the water duct. The outlet portion has a variable outlet nozzle which can discharge water downwardly when desired to produce a lift force for lifting the stern of the vessel. The arrangement provides an improved rolling stability under a stationary condition and is also effective to decrease a drag force under the "hump" condition.