The enhancement of seakeeping qualities of fast catamaran by means of stabilizing foils

Some aspects of insufficient seakeeping qualities of fast catamarans are commonly known. The intention of this investigations was to obtain quantitative data about the influence of application of hydrofoils on seakeeping qualities of a fast catamaran. Two types of foils were investigated: single foil spread between the hulls and double T - foils under the bows. Three locations of a single foil over the ship length and three angles of attack were tested. The comparsion was made between resistance, accelerations, heave and pitch in irregular head waves of the ship with and without foils. Quantitative effects of foils in different configurations and different sea and operation conditions were estimated.