CATAMARAN Russian patent published in 1994 - IPC

FIELD: shipbuilding. SUBSTANCE: catamaran consists of two hulls made symmetrically or assymmetrically relative to their own CL and connected by means of deck. Mounted between the hulls below the waterline are at least three hydrofoils: two trimming hydrofoils are located in the fore and aft extremities of the catamaran and at least one center unloading hydrofoil is located between the abovementioned two hydrofoils. Fore and aft trimming hydrofoils are removed from the center of mass of catamaran along its length at distances equal respectively to at least 30 percent and 20 percent of the catamaran hull length. The point of application of the lift force is shifted towards fore extremity of the catamaran from its center of mass by distance equal to 5 to 20 percent of the catamaran hull length. When catamaran is running in swell and at heaving motion (vertical oscillations of the hulls), immersion-emersion takes place which cause increase-decrease of the lift force: lift force is increased during immersion and is decreased during emersion, thus reducing the amplitudes of vertical motion. In case of pitching (ship's oscillations about transverse axis), force or aft hydrofoil gets in turn near the free surface and other hydrofoil is considerably immersed. Thus, stabilizing moment arises which reduces amplitudes of pitching. EFFECT: enhanced reliability. 4 cl, 3 dwg