GB493176A - Improvements in and relating to hydroplanes - Google Patents

Abstract

493,176. Hydroplanes. BURTENBACH, H. F. S. VON. Nov. 18, 1937, No. 31758. [Class 113 (ii)] A hydroplane having transversely stepped, gliding surfaces on the bottom of the hull and adapted to be supported in motion by lifting planes disposed under the hull which are inclined in the transverse direction and extend partly above and partly below the water level, are arranged so that the stepped individual gliding surfaces of the hull are spaced as widely as possible in both transverse and longitudinal directions on the craft and are disposed to assist in stabilizing the main lifting planes which are located directly below the spaces of the gliding surfaces. A hydroplane is provided at the bow with gliding surfaces a underneath which is the lifting plane fa, whilst, at the stern, are hull gliding surfaces b<1>, b<2> below which is a lifting plane fb. The hull may have an intermediate plane i beneath a step, and further there may be auxiliary lifting planes g at the bow. In an alternative, the planes fb are placed slightly forward of the stem, and further planes fc co-operate with gliding surfaces e on the craft at the stern. The gliding surfaces of the hull may be keeled or not and are arranged at the forward part with an inclination which is always positive, even when the boat is down at the nose. Supplementary lifting surfaces g and gliding surfaces e may be disposed at the bow. The lifting planes may be disposed directly on the hull, and are preferably set at a transverse angle from 25 to 30‹, but they may be supported by struts s. Further, these planes may have a re-entrant angle at the centre. In one form, the strut is supported by a frangible pin from a bracket on the hull which yields when the strut meets an obstruction. Preferably, the propellers are disposed below the aft lifting plane behind which may be the rudder. Alternatively, the strut s may be constituted by part of a rudder. In some constructions, the angle of the lifting planes may be adjusted, the planes being pivotally mounted and linked to a member which may be manually operated or automatically operated by hydraulic pressure acting against a spring. Various cross-sections of the lifting surfaces are shown in Figs. 17 to 22.