Patent ID: 7779771

Claim:
A method for breaking ice with a motor-driven watercraft with three hulls, i.e. a trimaran, comprising a middle hull having, a bow, a propulsion device, a right side hull and a left side hull and a deck, wherein said three hulls extend in a longitudinal direction and are attached to define a whole width of said trimaran, comprising the steps of: ice breaking by hitting the ice with the bow of the middle hull of the trimaran, leaving ice on either side of the middle hull; followed by hitting the ice with the right side hull, and the left side hull, which are situated further back than the middle hull in the longitudinal direction of the watercraft so that the hitting of the ice by the right side hull, and the left side hull takes place substantially later than ice breaking by the bow of the middle hull; and wherein the right side hull, and the left side hull, bend down and thus break the ice that is left on the sides of the middle hull, so that a broken passage having essentially the width of the whole watercraft including the side hulls, is formed in the ice.