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31-491: The Multi One Design 70 (MOD 70) is a 21.2-metre (70 ft) multihull one-design yacht class, named after the Multi One Design company, created in 2009. The MOD 70 is a class of trimaran boats. This sailing -related article is a stub . You can help Misplaced Pages by expanding it . Multihull Single-outrigger boats , double-canoes ( catamarans ), and double-outrigger boats ( trimarans ) of

62-686: A multihull vessel can be narrower than that of a monohull with the same displacement and long, narrow hulls, a multihull typically produces very small bow waves and wakes , a consequence of a favorable Froude number . Vessels with beamy hulls (typically monohulls) normally create a large bow wave and wake. Such a vessel is limited by its "hull speed", being unable to "climb over" its bow wave unless it changes from displacement mode to planing mode. Vessels with slim hulls (typically multihulls) will normally create no appreciable bow wave to limit their progress. In 1978, 101 years after catamarans like Amaryllis were banned from yacht racing they returned to

93-461: A narrow hull needs. While the aft sponsons act as trimaran sponsons do, the front sponsons do not touch the water normally; only if the ship rolls to one side do they provide added buoyancy to correct the roll. BMT Group , a shipbuilding and engineering company in the UK , has proposed a fast cargo ship and a yacht using this kind of hull. Multihull designs may have hull beams that are slimmer at

124-725: A new population by a very small number of individuals from a larger population, which also causes a loss of genetic variation. Soares et al. (2008) argued for an older pre- Holocene Sundaland origin in Island Southeast Asia (ISEA) based on mitochondrial DNA . The "out of Taiwan" model was challenged by a study from Leeds University published in Molecular Biology and Evolution . Examination of mitochondrial DNA lineages indicates that they have been evolving in ISEA for longer than previously believed. Ancestors of

155-462: A proa can either be on the lee or windward side, or in a tacking proa, interchangeable. However, more recently, proas tend to keep the outrigger either to leeward or to wind which means that instead of tacking, a "shunt" is required, whereby the bow becomes the stern, and the stern becomes the bow. A catamaran is a vessel with twin hulls. Commercial catamarans began in 17th century England. Separate attempts at steam-powered catamarans were carried out by

186-421: Is a canoe with a slender outrigger ("ama") attached by two or more struts ("akas"). This craft will normally be propelled by paddles. Single-outrigger canoes that use sails are usually inaccurately referred to by the name " proa ". While single-outrigger canoes and proas both derive stability from the outrigger, the proa has the greater need of the outrigger to counter the heeling effect of the sail. The outrigger on

217-727: The Austronesian peoples are the direct antecedents of modern multihull vessels. They were developed during the Austronesian Expansion (c. 3000 to 1500 BC) which allowed Austronesians to colonize maritime Southeast Asia , Micronesia , Island Melanesia , Madagascar , and Polynesia . These Austronesian vessels are still widely used today by traditional fishermen in Austronesian regions in maritime Southeast Asia, Oceania and Madagascar; as well as areas they were introduced to by Austronesians in ancient times like in

248-874: The East African coast and in South Asia . Greek sources also describe large third-century BC catamarans, one built under the supervision of Archimedes , the Syracusia , and another reportedly built by Ptolemy IV Philopator of Egypt , the Tessarakonteres . Modern pioneers of multihull design include James Wharram (UK), Derek Kelsall (UK), Tom Lack (UK), Lock Crowther (Aust), Hedly Nicol (Aust), Malcolm Tennant (NZ), Jim Brown (USA), Arthur Piver (USA), Chris White (US), Ian Farrier (NZ), LOMOcean (NZ), Darren Newton (UK), Jens Quorning (DK) and Dick Newick (USA). A single-outrigger canoe

279-990: The Marquesas . From here, they expanded further to Hawaii by 900 AD, Easter Island by 1000 AD, and finally New Zealand by 1200 AD. Analysis by Kayser et al. (2008) found that only 21% of the Polynesian autosomal gene pool is of Australo-Melanesian origin, with the remaining 79% being of Austronesian origin. Another study by Friedlaender et al. (2008) also confirmed that some Polynesians are genetically closer to Micronesians , Taiwanese Aborigines , and Islander Southeast Asians . The study concluded that Polynesians moved through Melanesia fairly rapidly, allowing only limited admixture between Austronesians and Papuans. Polynesians predominantly belong to Haplogroup B (mtDNA), particularly to mtDNA B4a1a1 (the Polynesian motif). The high frequencies of mtDNA B4 in Polynesians are

310-945: The United States ( Hawaii and American Samoa ), as well as in the British Overseas Territory of the Pitcairn Islands . New Zealand had the highest population of Polynesians, estimated at 110,000 in the 18th century. Polynesians have acquired a reputation as great navigators, with their canoes reaching the most remote corners of the Pacific and allowing the settlement of islands as far apart as Hawaii, Rapanui (Easter Island), and Aotearoa (New Zealand). The people of Polynesia accomplished this voyaging using ancient navigation skills, including reading stars, currents, clouds, and bird movements—skills that have been passed down through successive generations to

341-503: The 1960s is down to the added space, speed, shallow draft, and lack of heeling underway. The stability of a multihull makes sailing much less tiring for the crew, and is particularly suitable for families. Having no need for ballast for stability, multihulls are much lighter than monohull sailboats; but a multihull's fine hull sections mean that one must take care not to overload the vessel. Powerboats catamarans are increasingly used for racing, cruising and as workboats and fishing boats. Speed,

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372-564: The Polynesians are believed to be the Neolithic Lapita culture . This group emerged in Island Melanesia and Micronesia around 1500 BC from a convergence of Austronesian migration waves, originating from both Island Southeast Asia to the west and an earlier Austronesian migration to Micronesia to the north. The culture was distinguished by dentate-stamped pottery. However, their eastward expansion halted when they reached

403-569: The Polynesians arrived in the Bismarck Archipelago of Papua New Guinea at least 6,000 to 8,000 years ago. A 2014 study by Lipson et al., using whole genome data , supports the findings of Kayser et al. Modern Polynesians were shown to have lower levels of admixture with Australo-Melanesians than Austronesians in Island Melanesia . Nonetheless, both groups show admixture, along with other Austronesian populations outside of Taiwan, indicating varying degrees of intermarriage between

434-674: The bulk of the charter business) and Australia. Multihulls are less common in the US, perhaps because their increased beam require wider dock/slips. Smaller multihulls may be collapsible and trailerable, and thus suitable for daybooks and racers. Until the 1960s most multihull sailboats (except for beach cats) were built either by their owners or by boat builders; since then companies have been selling mass-produced boats, of which there are more than 150 models. Polynesians Polynesians are an ethnolinguistic group comprising closely related ethnic groups native to Polynesia , which encompasses

465-466: The crossbeams (or "akas"). Small beachable catamarans, such as the Hobie Cat , also have only a trampoline between the hulls. Catamarans derive stability from the distance between the hulls—transverse clearance—the greater this distance, the greater the stability. Typically, catamaran hulls are slim, although they may flare above the waterline to give reserve buoyancy. The vertical clearance between

496-564: The design waterplane and the bottom of the bridge deck determines the likelihood of contact with waves. Increased vertical clearance diminishes such contact and increases seaworthiness , within limits. A trimaran (or double-outrigger) is a vessel with two outrigger floats attached on either side of a main hull by a crossbeam, wing, or other form of superstructure. They are derived from traditional double-outrigger vessels of maritime Southeast Asia. Despite not being traditionally Polynesian, western trimarans use traditional Polynesian terms for

527-399: The end of 2023. A French manufacturer, Tera-4, produces motor quadrimarans which use aerodynamic lift between the four hulls to promote planing and reduce power consumption. Design concepts for vessels with two pair of outriggers have been referred to as pentamarans. The design concept comprises a narrow, long hull that cuts through waves. The outriggers then provide the stability that such

558-469: The experimental ship RV Triton and the Independence class of littoral combat ships (US). Some multihulls with four (quadrimaran) or five (pentamaran) hulls have been proposed; few have been built. In 2018 a Swiss entrepreneur sought funding to build a sail-driven quadrimaran called Manta that would use solar power to scoop plastic from the ocean. Manta was still under development as of

589-402: The first humans to cross vast distances of water on ocean-going boats. Despite the popularity of rejected hypotheses, such as Thor Heyerdahl 's belief that Polynesians are descendants of "bearded white men" who sailed on primitive rafts from South America , Polynesians are believed to have originated from a branch of the Austronesian migrations in Island Melanesia . The direct ancestors of

620-466: The genetics of modern Polynesians (as well as Islander Melanesians ) occurred after the settlement of Tonga and Vanuatu . A 2020 study found that Polynesians and the Indigenous peoples of South America came in contact around 1200, centuries before Europeans interacted with either group. There are an estimated 2 million ethnic Polynesians and many of partial Polynesian descent worldwide,

651-543: The hull ( vaka ), the floats ( ama ), and connectors ( aka ). The word trimaran is a portmanteau of tri and (cata)maran , a term that is thought to have been coined by Victor Tchetchet , a pioneering modern multihull designer, born in Ukraine (at that time part of the Russian Empire ). Some trimaran configurations use the outlying hulls to enhance stability and allow for shallow draft, examples include

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682-409: The incoming Neolithic Austronesian settlers and the preexisting Paleolithic Australo-Melanesian populations of Island Southeast Asia and Melanesia . Studies from 2016 and 2017 also support the idea that the earliest Lapita settlers mostly bypassed New Guinea, coming directly from Taiwan or the northern Philippines . The intermarriage and admixture with Australo-Melanesian Papuans evident in

713-1195: The islands within the Polynesian Triangle in the Pacific Ocean . They trace their early prehistoric origins to Island Southeast Asia and are part of the larger Austronesian ethnolinguistic group, with an Urheimat in Taiwan . They speak the Polynesian languages , a branch of the Oceanic subfamily within the Austronesian language family . The Indigenous Māori people form the largest Polynesian population, followed by Samoans , Native Hawaiians , Tahitians , Tongans , and Cook Islands Māori . As of 2012 , there were an estimated 2 million ethnic Polynesians (both full and part) worldwide. The vast majority either inhabit independent Polynesian nation-states ( Samoa , Niue , Cook Islands , Tonga , and Tuvalu ) or form minorities in countries such as Australia , Chile ( Easter Island ), New Zealand , France ( French Polynesia and Wallis and Futuna ), and

744-429: The middle of the 20th century. However, success required better materials and more developed hydrodynamic technologies. During the second half of the 20th century catamaran designs flourished. Catamaran configurations are used for racing, sailing, tourist and fishing boats. The hulls of a catamaran are typically connected by a bridgedeck, although some simpler cruising catamarans simply have a trampoline stretched between

775-463: The present day. Polynesians, including Samoans , Tongans , Niueans , Cook Islands Māori , Tahitian Mā'ohi , Hawaiian Māoli , Marquesans , and New Zealand Māori , are a subset of the Austronesian peoples . They share the same origins as the indigenous peoples of Taiwan , Maritime Southeast Asia , Micronesia , and Madagascar . This is supported by genetic , linguistic and archaeological evidence. There are multiple hypotheses regarding

806-406: The result of genetic drift and represent the descendants of a few Austronesian females who mixed with Papuan males. The Polynesian population experienced a founder effect and genetic drift due to the small number of ancestors. As a result of the founder effect, Polynesians are distinctively different both genotypically and phenotypically from the parent population, due to the establishment of

837-515: The sport. This started with the victory of the trimaran Olympus Photo , skippered by Mike Birch in the first Route du Rhum . Thereafter, no open ocean race was won by a monohull. Winning times dropped by 70%, since 1978. Olympus Photo's 23-day 6 hr 58' 35" success dropped to Gitana 11's 7d 17h 19'6", in 2006. Around 2016 the first large wind driven foil-borne racing catamarans were built. These cats rise onto foils and T-foiled rudders only at higher speeds. The increasing popularity of catamaran since

868-539: The stable working platform, safety, and added space are the prime advantages for power cats. "The weight of a multihull, of this length, is probably not much more than half the weight of a monohull of the same length and it can be sailed with less crew effort." Racing catamarans and trimarans are popular in France, New Zealand and Australia. Cruising cats are commonest in the Caribbean and Mediterranean (where they form

899-460: The ultimate origin and mode of dispersal of the Austronesian peoples , but the most widely accepted theory is that modern Austronesians originated from migrations out of Taiwan between 3000 and 1000 BC. Using relatively advanced maritime innovations such as the catamaran , outrigger boats , and crab claw sails , they rapidly colonized the islands of both the Indian and Pacific oceans. They were

930-602: The water surface ("waterplane") than underwater. This arrangement allows good wave-piercing, while keeping a buoyant hydrodynamic hull beneath the waterplane. In a catamaran configuration this is called a small waterplane area twin hull , or SWATH. While SWATHs are stable in rough seas, they have the drawbacks, compared with other catamarans, of having a deeper draft, being more sensitive to loading, and requiring more power because of their higher underwater surface areas. Triple-hull configurations of small waterplane area craft had been studied, but not built, as of 2008. Each hull of

961-533: The western Polynesian islands of Fiji , Samoa , and Tonga by around 900 BC. This remained the furthest extent of the Austronesian expansion in the Pacific for approximately 1,500 years, during which the Lapita culture in these islands abruptly lost the technology of pottery-making for unknown reasons. They resumed their eastward migrations around 700 AD, spreading to the Cook Islands , French Polynesia , and

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