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Furl (sailing)
Furling refers to stowing or dousing a boat's sail by flaking (folding), packing (like stuffing a spinnaker into a bag), or stowing it in part or whole using roller furling. Furling is not synonymous with ''dousing'' (dropping) or reefing Reefing reduces the area of a sail, usually by folding or rolling one edge of the canvas in on itself and attaching the unused portion to a spar or a stay, as the primary measure to preserve a sailing vessel's stability in strong winds. Restoring ... (reducing the exposed area of) a sail, but modern technologies such as roller furling are altering the term's traditional use. Sailing rigs and rigging {{Water-transport-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sail
A sail is a tensile structure—which is made from fabric or other membrane materials—that uses wind power to propel sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles. Sails may be made from a combination of woven materials—including canvas or polyester cloth, laminated membranes or bonded filaments—usually in a three- or four-sided shape. A sail provides propulsive force via a combination of lift and drag, depending on its angle of attack—its angle with respect to the apparent wind. Apparent wind is the air velocity experienced on the moving craft and is the combined effect of the true wind velocity with the velocity of the sailing craft. Angle of attack is often constrained by the sailing craft's orientation to the wind or point of sail. On points of sail where it is possible to align the leading edge of the sail with the apparent wind, the sail may act as an airfoil, generating propulsive force as air p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinnaker
A spinnaker is a sail designed specifically for sailing off the wind on courses between a reach (wind at 90° to the course) to downwind (course in the same direction as the wind). Spinnakers are constructed of lightweight fabric, usually nylon, and are often brightly colored. They may be designed to perform best as either a reaching or a running spinnaker, by the shaping of the panels and seams. They are attached at only three points and said to be ''flown''. Nomenclature Informal names for a spinnaker are ''kite'' or ''chute'' (owing to their resemblance to a parachute in both construction and appearance). Boats may have more than one spinnaker, differentiated by a letter to indicate symmetric (S) or asymmetric (A) and a number to indicate size (with higher numbers indicating smaller size), e.g. ''A1'' would be a large asymmetric sail and ''S3'' would be a smaller symmetric sail. Operation A spinnaker is used for sailing with the direction of the wind. Symmetrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roller Furling
Roller furling is a method of furling (i.e. reefing) a yacht's staysail by rolling the sail around a stay. Roller furling is typically used for foresails such as jibs or genoas. A mainsail may also be furled by a similar system, whereby the sail is furled within the mast or around a rotating boom (or around a rotating shaft within a boom). Although staysail roller-furling is effective and very common, in-mast or in-boom mainsail furling involves some compromises, and mainsail slab reefing gives a better sail shape. Methods The idea for a furling jib is usually attributed to Major E du Boulay in England who invented a device similar to a roller blind for reefing a jib. Major Wykeham-Martin used one of Boulay's rollers and improved the system by incorporating roller bearings in 1907 when the system was patented. The original castings were made by London-based toilet makers Bouldings. By the 1940s nearly every British cruising yacht was fitted with this furling system. An early v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reefing
Reefing reduces the area of a sail, usually by folding or rolling one edge of the canvas in on itself and attaching the unused portion to a spar or a stay, as the primary measure to preserve a sailing vessel's stability in strong winds. Restoring full sail area is termed ''shaking out'' a reef. Whereas fore-and-aft rigged vessels store the unused portion of the sail on a boom, below the sail, square-rigged vessels stow the unused portion on a spar, above the sail. Reefing may occur by rolling the sail around its luff or foot, either on a rotating stay or within a spar. Fore-and-aft rigs Sails may have built-in alternative attachment points that allow their area to be reduced. In a mainsail, pairs of grommets, called reefing tacks, reefing clews, or reefing cringles may be installed in the sail; a cruising boat will typically have two to three pairs. Pulling these points down to the boom forms a new tack and clew, reducing the sail's area. Using the pair of grommets closest t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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