The AC72 is a class of wingsail catamarans built to a box rule, which governs the construction and operation of yachts competing in the 2013 Louis Vuitton and the America's Cup races. The class was subsequently replaced by the smaller AC50 class.
Team New Zealand AC72, San Francisco Bay
A catamaran is a watercraft with two parallel hulls of equal size. The distance between a catamaran's hulls imparts resistance to rolling and overturning. Catamarans typically have less hull volume, smaller displacement, and shallower draft (draught) than monohulls of comparable length. The two hulls combined also often have a smaller hydrodynamic resistance than comparable monohulls, requiring less propulsive power from either sails or motors. The catamaran's wider stance on the water can reduce both heeling and wave-induced motion, as compared with a monohull, and can give reduced wakes.
A Formula 16 beachable catamaran
Powered catamaran passenger ferry at Salem, Massachusetts, United States
A carved and painted voyaging catamaran with tanja sails of the Micronesian inhabitants of Hermit Islands, Bismarck Archipelago (c. 1914)
1827 depiction of Tahitian pahi war-canoes