A series of self-propulsion tests of a catamaran design atmedium-speeds is proposed to study the influence of thehydrodynamics at medium-speeds on the waterjetpropulsors. These model tests will be carried out using aload-varied self-propulsion testing technique in calmwater. Due to size requirements of the model, a singledemihull is to be utilised in close proximity to the sidewall of the towing tank which acts as the plane ofsymmetry, reflecting waves generated by the demihull andtherefore providing the acceptable blockage effects andwave interference for the second demihull.