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Catamaran

A catamaran is a type of boat (or occasionally ship) consisting of two hulls joined by a frame. Catamarans can be sail- or motor-powered. The word catamaran comes from the Tamil language, in which the word kattumaram means "logs bound together". The catamaran was the invention of the paravas, an aristocratic fishing community in the southern coast of Tamilnadu, India. Catamarans were used by the ancient Tamil Chola dynasty as early as 5th century AD for moving their fleets to conquer such south-east Asian regions as Burma, Indonesia and Malaysia.
Catamarans are a relatively recent design of boat for both leisure and sport sailing, although they have been used for millennia in Oceania, where Polynesian catamarans allowed seafaring Polynesians to settle the world's most far-flung islands. Catamarans have been met by a degree of scepticism from some sailors accustomed to more "traditional" designs.

Catamaran sailing
Although the principles of sailing are the same for both catamarans and monohulls, there are some 'peculiarities' to sailing catamarans. For example:

Catamarans can be harder to tack (turn through the wind). Because they are lighter in proportion to their sail size, they have less momentum to carry them through the turn when they are head to wind.
They have a higher average speed.
All boats sail faster when travelling in certain directions relative to the wind the best speeds typically being achieved when heading away from the wind at about 135 degrees. This effect is much more noticeable with catamarans, even to the extent that it can be more efficient to jibe ('tack' downwind) in zig zags, rather than heading directly away from the wind as a monohull would.
Catamarans are less likely to capsize in the classic 'beam-wise' manner but often have a tendency to 'pole-axe' (or 'pitchpole') instead - where the leeward (downwind) bow sinks into the water and the boat 'trips' over forward, leading to a capsize.
Teaching for new sailors is usually carried out in monohulls as they are thought easier to learn to sail, a mixture of all the differences mentioned probably contributes to this.

Stars & Stripes, a racing catamaranCatamarans, and multihulls in general, are normally faster than single-hull boats for four reasons:

each hull of a catamaran is (typically) thinner in cross section than those of monohulls;
catamarans are lighter due to the fact there is no keel counterweight.
catamarans have a wider beam (the distance from one side of the boat to the other), which makes them more stable and therefore able to carry more sail area per metre of length than an equivalent monohull.
the greater stability means that the sail is more likely to stay upright in a gust, drawing more power than a monohull's sail which is more likely to lean over.
Catamarans are especially favourable in coastal waters, where the open spaces permit the boat to reach and maintain its maximum speed. Catamarans make good cruising and long distance boats: The Race (around the world, in 2001) was won by the giant catamaran Club Med skippered by Grant Dalton. It went round the earth in 62 days at an average speed of eighteen knots.

The Hobie cats
International A-Class (open design; length 5.49 m (18 ft), beam 2.3 m (7 ft 6.5 in), weight 75 kg, sail 13.94 m² (150 ft²))
Dart 15 and Dart 18
Tornado, Olympic class racing catamaran.
Catamarans for ferries:

Stena Line HSS class (High-speed Sea Service)
Stena Discovery - Harwich, UK to Hoek van Holland, Netherlands
Stena Voyager - Stranraer to Belfast
Stena Explorer - Holyhead to Dun Laoghaire, Republic of Ireland
Lake Express running between Milwaukee, Wisconsin and Muskegon, Michigan
Spirit of Ontario I running between Rochester, New York and Toronto, Ontario
SSTH Ocean Arrow
SuperStar Express, P&O Irish Sea running between Troon, Scotland and Belfast, Northern Ireland.
FoilCat, FlyingCat and Tricat operated by Turbojet Ferry, running between Hong Kong and Macau.
The Cat, a high speed car ferry running various routes between Canada's Atlantic provinces and the mainland, which includes a line between Portland, Maine in the United States and Yarmouth, Nova Scotia in Canada.
A modern interpretation of the traditional catamaran can be found at [1], designed by James Wharram.
EMERGENCE OF THE POWER CATAMARAN

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