Trimaran Trimaran A trimaran (or double-outrigger) is a multihull boat that comprises a main hull and two smaller outrigger hulls (or "floats") which are attached to the main hull with lateral beams. Most trimarans are sailing yachts designed for recreation or racing; others are ferries or warships. The word "trimaran" is a portmanteau of "Tri" and "(Cata)maran". It is thought to have been invented by Victor Tchetchet, a pioneering, Ukrainian-born modern multihull designer. The first trimarans were developed by the Austronesian people and are still widely used today by traditional fishermen in maritime Southeast Asia, Madagascar, Micronesia, and Polynesia. Some of
Pontoon effect a trimaran with narrow-beam floats will simply submerge the lee float, exposing only the weather wing and that with a lesser moment. In practical sea situations the windage effect is greater than the buoyancy effect and so cruising trimarans with highly buoyant floats are more, not less, likely to capsize than those with less buoyant floats. A trimaran is best stabilised not by adding buoyancy on the lee float but adding weight to the weather float. This is the basis of the "cool-tubes" stability system invented by Tristan Jones and L. Surtees. A large-diameter pipe closed at the aft end