THE DYNAPLANE DESIGN FOR PLANING MOTORBOATS An improved design for planing motorboats (the Dynaplane) attains planing speeds with only half the horsepower required by conventional planing motorboats. Accordingly, Dynaplane boats have half the fuel consumption, and produce half the pollution as conventional types. This efficient design is the result of extensive theoretical and experimental work in hydrodynamics. The extremely low drag has been verified by model tests at the U.S. Navy and at Stevens Institute of Technology. The Dynaplane is a stepped craft with a short planing region near midlength and an adjustable Vee hydrofoil at the stern. Approximately 90% of the weight is carried by the amidships planing region which incorporates the features of camber, relatively high aspect ratio, and trim control (provided by the adjustable stern stabilizer). These advantageous features result in very low values of both frictional resistance and pressure drag. The adjustable hydrofoil at the stern makes it possible to trim the boat to the optimum angle for different speeds and loads, and also to adapt advantageously to various water-surface conditions.