Abstract: A catamaran includes a pair of floats, a deck extending in the air between the pair of floats as fixedly attached thereto and a connecting member extending in the water between the pair of floats as fixedly attached thereto. The connecting member has an airfoil-shaped section so that a lift is provided to the bow of the catamaran while it is cruising. Preferably, the airfoil-shaped section is inclined to define an attack angle in a range between 15 degrees and 25 degrees and most preferably approximately at 20 degrees. When applied to a working catamaran having a rotating impeller for collecting floats, a tail section is provided as extending downstream from a downstream edge of the air-foiled section.

Abstract: A spilled oil collection catamaran includes a submerged waterfoil extending between a pair of floats and submerged at its bow, a rotating impeller extending between the floats and above the waterfoil with its bottom partly dipped in the water, a spraying pipe extending between the floats and in front of the impeller for spraying a gelling agent for having the spilled oil drifting in the water surface gelled, and a vertically movable cage in the rear of the impeller for housing therein a porous collection bag which has an open side directed toward the bow to collect gelled oil in the bag. The catamaran also includes a spray gun at the bow for spraying the gelling agent over the spilled oil drifting in the water surface in front of the catamaran.