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 bridge consisted of one or more pontoons, which were maneuvered into position and then anchored underwater or on land. The pontoons were linked together using wooden stringers called "balks". The balks were covered by a series of cross planks called "chesses" to form the road surface, and the chesses were secured with side guard rails. A floating bridge can be built in a series of sections, starting from an anchored point on the shore. Modern pontoon bridges usually use pre-fabricated floating structures. Most pontoon bridges are designed for temporary use, but bridges across water bodies with a constant water level can