This paper deals with an experimental investigation of the heave and pitch motions in waves of an IACC yacht. The seakeeping tests of a fully appended scale model have been carried out at the towing tank of the University of Trieste. A single hull has been tested with different bulb configurations to check the influence of the bulb shape on the performance of the yacht in waves. Three bulb shapes of different length have been developed using multi-objective optimization and process integration, in order to obtain three shapes with minimum drag in calm water and with lowest VCG, satisfying length and volume constraints. The results presented are the Response Amplitude Operators for the vertical motion and the total mean resistance in regular waves
