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Close-hauled
A point of sail is a sailing craft's direction of travel under sail in relation to the true wind direction over the surface. The principal points of sail roughly correspond to 45° segments of a circle, starting with 0° directly into the wind. For many sailing craft 45° on either side of the wind is a ''no-go'' zone, where a sail is unable to mobilize power from the wind. Sailing on a course as close to the wind as possible—approximately 45°—is termed ''beating'', a point of sail when the sails are ''close-hauled''. At 90° off the wind, a craft is on a ''beam reach''. The point of sail between beating and a beam reach is called a ''close reach''. At 135° off the wind, a craft is on a ''broad reach''. At 180° off the wind (sailing in the same direction as the wind), a craft is ''running downwind''. A given point of sail (beating, close reach, beam reach, broad reach, and running downwind) is defined in reference to the true wind—the wind felt by a stationary observe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Points Of Sail
A point of sail is a sailing craft's Course (navigation), direction of travel under sail in relation to the true wind direction over the surface. The principal points of sail roughly correspond to 45° segments of a circle, starting with 0° directly into the wind. For many sailing craft 45° on either side of the wind is a ''no-go'' zone, where a sail is unable to mobilize power from the wind. Sailing on a course as close to the wind as possible—approximately 45°—is termed ''beating'', a point of sail when the sails are ''close-hauled''. At 90° off the wind, a craft is on a ''beam reach''. The point of sail between beating and a beam reach is called a ''close reach''. At 135° off the wind, a craft is on a ''broad reach''. At 180° off the wind (sailing in the same direction as the wind), a craft is ''running downwind''. A given point of sail (beating, close reach, beam reach, broad reach, and running downwind) is defined in reference to the #True wind versus apparent win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forces On Sails
Forces on sails result from movement of air that interacts with sails and gives them motive power for sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and sail-powered land vehicles. Similar principles in a rotating frame of reference apply to windmill sails and wind turbine blades, which are also wind-driven. They are differentiated from forces on wings, and propeller blades, the actions of which are not adjusted to the wind. Kites also power certain sailing craft, but do not employ a mast to support the airfoil and are beyond the scope of this article. Forces on sails depend on wind speed and direction and the speed and direction of the craft. The direction that the craft is traveling with respect to the "true wind" (the wind direction and speed over the surface) is called the point of sail. The speed of the craft at a given point of sail contributes to the "apparent wind"—the wind speed and direction as measured on the moving craft. The appare ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sailing
Sailing employs the wind—acting on sails, wingsails or kites—to propel a craft on the surface of the ''water'' (sailing ship, sailboat, raft, Windsurfing, windsurfer, or Kitesurfing, kitesurfer), on ''ice'' (iceboat) or on ''land'' (Land sailing, land yacht) over a chosen Course (navigation), course, which is often part of a larger plan of navigation. From prehistory until the second half of the 19th century, sailing craft were the primary means of maritime trade and transportation; exploration across the seas and oceans was reliant on sail for anything other than the shortest distances. Naval power in this period used sail to varying degrees depending on the current technology, culminating in the gun-armed sailing warships of the Age of Sail. Sail was slowly replaced by steam as the method of propulsion for ships over the latter part of the 19th century – seeing a gradual improvement in the technology of steam through a number of developmental steps. Steam allowed schedul ... [...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 pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tacking (sailing)
Tacking or coming about is a sailing maneuver by which a sailing craft ( sailing vessel, ice boat, or land yacht), whose next destination is into the wind, turns its bow toward and through the wind so that the direction from which the wind blows changes from one side of the boat to the other, allowing progress in the desired direction. Sailing vessels are unable to sail higher than a certain angle towards the wind, so "beating to windward" in a zig-zag fashion with a series of tacking maneuvers, allows a vessel to sail towards a destination that is closer to the wind than the vessel can sail directly. A sailing craft whose course is downwind jibes (or "wears" if square-rigged) by having the apparent wind cross the stern from one tack to the other. High-performance sailing craft may tack, rather than jibe, downwind, when the apparent wind is well forward. Beating to windward Sails are limited in how close to the direction of the wind they can power a sailing craft. The ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceboating
An iceboat (occasionally spelled ice boat or traditionally called an ice yacht) is a recreational or competition sailing craft supported on metal runners for traveling over ice. One of the runners is steerable. Originally, such craft were boats with a support structure, riding on the runners and steered with a rear blade, as with a conventional rudder. As iceboats evolved, the structure became a frame with a seat or cockpit for the iceboat sailor, resting on runners. Steering was shifted to the front. Because of their low resistance to forward motion over ice, iceboats are capable of speeds exceeding . Because of their speed, iceboats are used both for recreation and for racing. Racing craft typically carry one person. A related activity, land sailing, employs sailing craft similar to iceboats, but riding on wheels instead of runners. History The history of iceboating began in Europe in areas where smooth ice was found in the bays of the Baltic Sea and the canals of the N ... [...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 Point of sail#Reaching, reach (wind at 90° to the course) to Point of sail#Running downwind, 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''. Etymology Some dictionaries suggest that the origin of the word could be traced to the first boat to commonly fly a spinnaker, a yacht called ''Sphinx'', mispronounced as ''Spinx''. ''Spinnaker'' entry in The Concise Oxford Dictionary of English Etymology (1996). Oxford University PressAccording to encyclopedia.com Both retrieved on 20 July 2008. ''Sphinx'' first set her spinnaker in the Solent in 1865, and the first recorded use of the word was in 1866 in the Augu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velocity Made Good
Velocity made good, or VMG, is a term used in sailing, especially in yacht racing, indicating the speed of a sailboat towards (or from) the direction of the wind. The concept is useful because a sailboat cannot sail directly upwind, and thus often can not, or should not, sail directly to a mark to reach it as quickly as possible. It is also often less than optimal to sail directly downwind. Concept Instead of sailing directly toward a windward mark, the helmsman chooses a point of sail towards the direction of the wind that maximizes velocity made good (either towards the destination - or towards better winds). To actually reach a mark, the boat needs to alternate between courses (''tacks'') where the wind approaches from alternating sides. The helmsman uses VMG to find exactly what the optimum angle against the wind is. At the optimum boat speed and angle to the wind, VMG is maximized, steering closer to the direction of the wind will reduce boat speed, while steering further awa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Studding Sail
A studding sail, or stun'sl (pronounced stuns'l ) is an extra sail on a square rigged vessel for use in fair weather. It is set outside the square sails, using stun'sl booms which run out along the yards. They came into use some time in the middle of the 17th century and by the beginning of the 19th century were usual on all square rigged sailing vessels. They started to become less common in the last quarter of the 19th century, as the economies of smaller crews and avoidance of damage to the ship's gear became more important than a fast voyage. History The origins of studding sails are relatively uncertain. The earliest reference is in 1655, but precise information on how these early examples were rigged is unknown. It is not until 1790 that this is available. Some changes in the detail of design and usage occurred over succeeding years. All ordinary working square-rigged vessels were usually fitted out to set stun'sls by the start of the 19th century. This started to change ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
