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23-420: The World Series uses AC45 catamarans, a one-design wingsail catamaran designed specifically for the event by Oracle Racing . The AC45 was conceived as a smaller version of the larger AC72 class rule which was used for the 2013 America's Cup . In 2015, the class was modified to AC45F which incorporated hydrofoiling capability for improved performance, with boats achieving peak speeds of 37kt. The AC45 has

46-432: A better lift-to-drag ratio , than traditional sails. Wingsails are more complex and expensive than conventional sails. Wingsails are of two basic constructions that create an airfoil, "soft" and "hard", both mounted on an unstayed rotating mast. Whereas hard wingsails are rigid structures that are stowed only upon removal from the boat, soft wingsails can be furled or stowed on board. L. Francis Herreshoff pioneered

69-499: A boat with two staysails the inner sail is called the staysail , and the outer (foremost) is called the jib. This combination of two staysails is called a cutter rig (or in North America a yankee pair ) and a boat with one mast rigged with two staysails and a mainsail is called a cutter . On cruising yachts, and nearly all racing sailboats, the jib needs to be worked when tacking. On these yachts, there are two sheets attached to

92-424: A precursor rig that had jib and main , each with a two-ply sail with leading edges attached to a rotating spar. The C Class Catamaran class has been experimenting and refining wingsails in a racing context since the 60s. Englishman, John Walker, explored the use of wingsails in cargo ships and developed the first practical application for sailing yachts in the 1990s. Wingsails have been applied to small vessels, like

115-424: A shortened jib-only bowsprit extending into a centerline pod under the wing, flaring topsides, closed transoms, opened hulls with deep cockpits for binnacles and wheels, replacing the tiller. The authorization does not permit to lengthen the hulls. All other teams carried out similar experiments with the platform. Nine events were held between 2011 and 2012 in the lead up to the 2013 America's Cup . In August 2013,

138-543: Is a variable- camber aerodynamic structure that is fitted to a marine vessel in place of conventional sails . Wingsails are analogous to airplane wings , except that they are designed to provide lift on either side to accommodate being on either tack . Whereas wings adjust camber with flaps , wingsails adjust camber with a flexible or jointed structure (for hard wingsails). Wingsails are typically mounted on an unstayed spar—often made of carbon fiber for lightness and strength. The geometry of wingsails provides more lift, and

161-476: Is called the jib , and the innermost is called the staysail . Actually, all three sails are both jibs and staysails in the generic sense. Original usage in 18th and 19th century square-rigged ships distinguished between the fore staysail, set on the forestay running from the foremast head to the ship's peak, the foremost part of the hull, and the jibs set on stays running to the bowsprit. Jibs, but not staysails, could also be "set flying," i.e. not attached to

184-406: Is undesirable. Nielsen summarised the efficiencies of wingsails, compared with conventional sails, for different points of sail , as follows: Jib A jib is a triangular sail that sets ahead of the foremast of a sailing vessel . Its forward corner ( tack ) is fixed to the bowsprit , to the bows , or to the deck between the bowsprit and the foremost mast. Jibs and spinnakers are

207-514: The Naval Chronicle (1805)—"we perceived by the cut of their sails, then set, that they were French Ships of War"—is often cited as an early inspiration for the idiom. Sir Walter Scott used the expression to denote approval in the 1824 novel St. Ronan's Well : "If she disliked what the sailor calls the cut of their jib " . John Russell Bartlett later defined the idiom in his 1848 Dictionary of Americanisms as "The form of his profile,

230-502: The Optimist dinghy and Laser , to cruising yachts, and most notably to high-performance multihull racing sailboats, like USA-17 . The smallest craft have a unitary wing that is manually stepped. Cruising rigs have a soft rig that can be lowered, when not in use. High-performance rigs are often assembled of rigid components and must be stepped (installed) and unstepped by shore-side equipment. Wingsails change camber (the asymmetry between

253-584: The camber or curvature of the wing, raising the maximum lift coefficient —the lift a wing can generate—at lower air speeds (speed of the air passing over it). A wingsail has the same need for camber adjustment, as windspeed changes—a straighter camber curvature as windspeed increases, more curved as it decreases. Mechanisms for camber adjustment are similar for soft and hard wingsails. Each employs independent leading and trailing airfoil segments that are adjusted independently for camber. More sophisticated rigs allow for variable adjustment of camber with height above

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276-417: The clew of the jib to be abaft the mast, meaning the jib and mainsail overlap. An overlapping jib is called a genoa jib or simply a genoa (see illustration). These are efficiently used when reaching more broadly than a close reach . Alternatively, a boat may carry smaller jibs, to compensate aerodynamics when the main sail is reefed ; these more rugged sails are called storm jibs or spitfires . On

299-415: The clew of the jib. As the yacht comes head to wind during a tack, the active sheet is released, and the other sheet (the lazy sheet ) on the other side of the boat is pulled in. This sheet becomes the new active sheet until the next tack. Schooners typically have up to three jibs. The foremost one sets on the topmast forestay and is generally called the jib topsail , a second on the main forestay

322-507: The 2019 and 2021 Louis Vuitton Cups Challenger Selection Series. These two seasons would have used the AC50 -class yachts, instead of the AC45 or AC45F classes. However, the winner of the 35th America's Cup, Emirates Team New Zealand was not a signatory to the agreement for the 36th and 37th America's Cup, making these plans obsolete. Wingsail A wingsail , twin-skin sail or double skin sail

345-445: The competition jury received a report from Oracle Team USA that their boat and others they had loaned had unauthorized modifications. Since they were using one of these modified boats, the BAR team withdrew from the competition on 7 August 2013. Oracle Team USA withdrew the day after. Penalties imposed included expelling three team members, a $ 250,000 fine, and a one-point penalty for each of

368-460: The first two races of the Match in which they would otherwise score a point. The series was revived as heats of nine two-day events in eight venues in the run up to the 2017 America's Cup . The races used a single boat design, known as AC45f, which was based on AC45 with added hydrofoil daggerboards and rudders. The overall winner of the competition was Land Rover BAR , with Oracle Team USA being

391-666: The following specifications: The AC45 are authorized to be taken out of measurement to serve as a testing platform for the America's Cup. Oracle Racing released photographs of an AC45 hydrofoiling with L-type appendages on June 18, 2012, a premonition of Team New Zealand's larger foiling AC72 Aotearoa test boat first spotted in Auckland on August 29, 2012. In February 2015 Oracle Racing and Artemis Racing tested two AC45s modified by Core Builders; They featured L-type hydrofoils, horizontal rudder stabilizers, lengthened crossbeams (herego wide beam),

414-493: The runner up. The winner of the series earned two points and the runner-up received a single point in the new America's Cup Qualifiers . The boats are similar to the AC50 used in the 2017 America's Cup . Prior to the 2017 America's Cup , several of the competing syndicates signed an agreement to hold World Series prior to the next two America's Cups, then scheduled for 2019 and 2021. These two World Series would be used as selection series to determine which teams would compete at

437-488: The standing rigging. Sails set beyond the peak were typically called jibs, set on stays running from the fore topmast to the bowsprit , or the fore topgallant mast to the jibboom or even the fore royal mast to the flying jibboom. A large square-rigged ship typically has four jibs, but could have as many as six. From forward to aft, these sails are called: The first two were rarely used except by clipper ships in light winds and were usually set flying. A storm jib

460-474: The top and the bottom surfaces of the aerofoil ), depending on tack and wind speed. A wingsail becomes more efficient with greater curvature on the downwind side. Since the windward side changes with each tack, so must sail curvature change. This happens passively on a conventional sail, as it fills in with wind on each tack. On a wingsail, a change in camber requires a mechanism. Wingsails also change camber to adjust for windspeed. On an aircraft, flaps increase

483-403: The two main types of headsails on a modern boat. Boats may be sailed using a jib alone, but more commonly jibs make a minor direct contribution to propulsion compared to a main sail . Generally, a jib's most crucial function is as an airfoil , increasing performance and overall stability by reducing turbulence on the main sail's leeward side. On boats with only one jib, it is common for

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506-502: The water to account for increased windspeed. The presence of rigging, supporting the mast of a conventional fore-and-aft rig limits sail geometry to shapes that are less efficient than the narrow chord of the wingsail. However, conventional sails are simple to adjust for windspeed by reefing . Wingsails typically are a fixed surface area. Conventional sails can be furled easily; some flexible wingsails can be dropped, when not in use; rigid wingsails must be removed when exposure to wind

529-481: Was a small jib of heavy canvas set to a stay to help to control the ship in bad weather. The jib is referenced in the idiom usually spoken as "I like the cut of your jib", generally seen as signifying approval of one's general appearance or respect for their character. The phrase alludes to the maritime practice of identifying far-away ships by noting the "cut" (general shape and configuration) of their sails to determine their status as friend or foe. One such report from

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