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102-485: Much like a co-operative, the Sailing Center owns and maintains over 80 boats and provides members no-charge access to the fleet after they successfully demonstrate basic sailing skills and earn a rating. Membership is low cost, less than the cost of insurance on a privately owned sailboat, and works on a sliding scale based on age, experience and income. The Sailing Center also offers private boat owners 24-hour access to

204-509: A halyard , and their angle with respect to the wind is usually controlled by a line, called a sheet . In use, they may be designed to be curved in both directions along their surface, often as a result of their curved edges. Battens may be used to extend the trailing edge of a sail beyond the line of its attachment points. Other non-rotating airfoils that power sailing craft include wingsails , which are rigid wing-like structures, and kites that power kite-rigged vessels , but do not employ

306-426: A better return on capital. In the 21st century, most sailing represents a form of recreation or sport . Recreational sailing or yachting can be divided into racing and cruising . Cruising can include extended offshore and ocean-crossing trips, coastal sailing within sight of land, and daysailing. Sailing relies on the physics of sails as they derive power from the wind, generating both lift and drag. On

408-453: A discovery or if no land was found. This was well suited to the prevailing winds as Pacific islands were steadily colonized. By the time of the Age of Discovery —starting in the 15th century—square-rigged, multi-masted vessels were the norm and were guided by navigation techniques that included the magnetic compass and making sightings of the sun and stars that allowed transoceanic voyages. During

510-530: A fleet of 10 Catalina 14.2s, 5 Club 420s, 6 RS-Touras, and 10 ILCA (formerly Laser) sailing dinghies. The MCSC support staff use a large fleet of safely boats, mostly Boston Whalers . Founded in 1977, the Milwaukee Community Sailing Center (MCSC) was created by a group of local sailors who sought to form a community organization to make sailing accessible to all in the Milwaukee area and dispel

612-409: A given course, the sails are set to an angle that optimizes the development of wind power, as determined by the apparent wind , which is the wind as sensed from a moving vessel. The forces transmitted via the sails are resisted by forces from the hull , keel , and rudder of a sailing craft, by forces from skate runners of an iceboat, or by forces from wheels of a land sailing craft which are steering

714-405: A lateral force, resisted by the underwater foils, ice runners, or wheels of the sailing craft. For apparent wind angles aligned with the entry point of the sail, the sail acts as an airfoil and lift is the predominant component of propulsion. For apparent wind angles behind the sail, lift diminishes and drag increases as the predominant component of propulsion. For a given true wind velocity over

816-414: A line or a hook may pass, as on Bermuda mainsails. Fore-and-aft sails may have tell-tales —pieces of yarn, thread or tape that are affixed to sails—to help visualize airflow over their surfaces. The lines that attach to and control sails are part of the running rigging and differ between square and fore-and-aft rigs. Some rigs shift from one side of the mast to the other, e.g. the dipping lug sail and

918-439: A mast to support the airfoil and are beyond the scope of this article. Sailing craft employ two types of rig, the square rig and the fore-and-aft rig . The square rig carries the primary driving sails on horizontal spars , which are perpendicular or square , to the keel of the vessel and to the masts. These spars are called yards and their tips, beyond the lifts , are called the yardarms . A ship mainly so rigged

1020-423: A parachute, with drag predominantly propelling the craft. For craft with little forward resistance, such as ice boats and land yachts , this transition occurs further off the wind than for sailboats and sailing ships . Wind direction for points of sail always refers to the true wind —the wind felt by a stationary observer. The apparent wind —the wind felt by an observer on a moving sailing craft—determines

1122-420: A sail is defined by its edges and corners in the plane of the sail, laid out on a flat surface. The edges may be curved, either to extend the sail's shape as an airfoil or to define its shape in use. In use, the sail becomes a curved shape, adding the dimension of depth or draft . Sail characteristics derive, in part, from the design, construction and the attributes of the fibers, which are woven together to make

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1224-471: A sail to reinforce it, or to fix the sail into a groove in the boom, in the mast, or in the luff foil of a roller-furling jib. They may have stiffening features, called battens , that help shape the sail, when full length, or just the roach, when present. They may have a variety of means of reefing them (reducing sail area), including rows of short lines affixed to the sail to wrap up unused sail, as on square and gaff rigs, or simply grommets through which

1326-400: A sailboat, point of sail affects lateral force significantly. The higher the boat points to the wind under sail, the stronger the lateral force, which requires resistance from a keel or other underwater foils, including daggerboard, centerboard, skeg and rudder. Lateral force also induces heeling in a sailboat, which requires resistance by weight of ballast from the crew or the boat itself and by

1428-407: A sailing craft turns downwind, the more drag increases and lift decreases as propulsive forces, until a sail going downwind is predominated by drag forces. Sails are unable to generate propulsive force if they are aligned too closely to the wind. Sails may be attached to a mast , boom or other spar or may be attached to a wire that is suspended by a mast. They are typically raised by a line, called

1530-434: A sailing craft turns its stern past the eye of the wind so that the apparent wind changes from one side to the other, allowing progress on the opposite tack. This maneuver can be done on smaller boats by pulling the tiller towards yourself (the opposite side of the sail). As with tacking, the type of sailing rig dictates the procedures and constraints for jibing. Fore-and-aft sails with booms, gaffs or sprits are unstable when

1632-693: A sailing yacht may be either near-shore or passage-making out of sight of land and entails the use of sailboats that support sustained overnight use. Coastal cruising grounds include areas of the Mediterranean and Black Seas, Northern Europe, Western Europe and islands of the North Atlantic, West Africa and the islands of the South Atlantic, the Caribbean, and regions of North and Central America. Passage-making under sail occurs on routes through oceans all over

1734-400: A series of broad reaches, punctuated by jibes in between. It was explored by sailing vessels starting in 1975 and now extends to high-performance skiffs, catamarans and foiling sailboats. Navigating a channel or a downwind course among obstructions may necessitate changes in direction that require a change of tack, accomplished with a jibe. Jibing or gybing is a sailing maneuver by which

1836-582: A shape that does not lie flat. Conventional sail panels are sewn together. Sails are tensile structures, so the role of a seam is to transmit a tensile load from panel to panel. For a sewn textile sail this is done through thread and is limited by the strength of the thread and the strength of the hole in the textile through which it passes. Sail seams are often overlapped between panels and sewn with zig-zag stitches that create many connections per unit of seam length. Whereas textiles are typically sewn together, other sail materials may be ultrasonically welded ,

1938-437: A smooth laminar flow , leading from one to the other in what is called the "slot effect". On downwind points of sail, power is achieved primarily with the wind pushing on the sail, as indicated by drooping tell-tales. Spinnakers are light-weight, large-area, highly curved sails that are adapted to sailing off the wind. In addition to using the sheets to adjust the angle with respect to the apparent wind, other lines control

2040-401: A technique whereby high frequency ultrasonic acoustic vibrations are locally applied to workpieces being held together under pressure to create a solid state weld . It is commonly used for plastics , and especially for joining dissimilar materials . Sails feature reinforcements of fabric layers where lines attach at grommets or cringles . A bolt rope may be sewn onto the edges of

2142-417: 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

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2244-575: A week on a fleet of over 80 boats, one of the largest among sailing non-profits anywhere. A four person full-time, year-round staff, expands to 40 during the sailing season, and serves a base of over 700 members and 600 youth participants annually. Members of the Milwaukee Community Sailing are able to participate in all programs the Sailing Center has to offer. Upon completion of appropriate courses and after successfully demonstrating basic sailing skills, individuals have no-charge access to

2346-423: A wider range of apparent wind angles than does an ice boat, whose speed is typically great enough to have the apparent wind coming from a few degrees to one side of its course, necessitating sailing with the sail sheeted in for most points of sail. On conventional sailboats, the sails are set to create lift for those points of sail where it's possible to align the leading edge of the sail with the apparent wind. For

2448-408: Is a maneuver by which a sailing craft turns its bow into and through the wind (referred to as "the eye of the wind" ) so that the apparent wind changes from one side to the other, allowing progress on the opposite tack. The type of sailing rig dictates the procedures and constraints on achieving a tacking maneuver. Fore-and-aft rigs allow their sails to hang limp as they tack; square rigs must present

2550-472: Is a private, non-profit agency that works to strengthen the sport of sailing through an active and safe educational program and on-the-water experience. The Milwaukee Community Sailing Center ( 43°02′42.76″N 87°53′12.0″W  /  43.0452111°N 87.886667°W  / 43.0452111; -87.886667 ) is located north of downtown in Veterans Park at McKinley Marina . The sailing area includes

2652-487: Is because the river's current flows from south to north, whilst the prevailing wind direction is north to south. Therefore, a boat of that time could use the current to go north – an unobstructed trip of 750 miles – and sail to make the return trip. Evidence of early sailors has also been found in other locations, such as Kuwait, Turkey, Syria, Minoa, Bahrain, and India, among others. Austronesian peoples used sails from some time before 2000 BCE. Their expansion from what

2754-412: Is called a square-rigger . A fore-and-aft rig consists of sails that are set along the line of the keel rather than perpendicular to it. Vessels so rigged are described as fore-and-aft rigged . The invention of the sail was a technological advance of equal or even greater importance than the invention of the wheel. It has been suggested by some that it has the significance of the development of

2856-480: Is governed by World Sailing with most racing formats using the Racing Rules of Sailing . It entails a variety of different disciplines, including: A saildrone is a type of unmanned surface vehicle used primarily in oceans for data collection. Saildrones are wind and solar powered and carry a suite of science sensors and navigational instruments. They can follow a set of remotely prescribed waypoints. The saildrone

2958-472: Is now Southern China and Taiwan started in 3000 BCE. Their technology came to include outriggers , catamarans , and crab claw sails , which enabled the Austronesian Expansion at around 3000 to 1500 BCE into the islands of Maritime Southeast Asia , and thence to Micronesia , Island Melanesia , Polynesia , and Madagascar . Since there is no commonality between the boat technology of China and

3060-432: 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

3162-413: Is on a broad reach. Boat velocity (in black) generates an equal and opposite apparent wind component (not shown), which combines with the true wind to become apparent wind. The speed of sailboats through the water is limited by the resistance that results from hull drag in the water. Ice boats typically have the least resistance to forward motion of any sailing craft. Consequently, a sailboat experiences

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3264-467: Is usually a "flow through" structure) and a number of intervisible islands create both an invitation to travel and an environment where advanced navigation techniques are not needed. Alongside this, the Nile has a northward flowing current with a prevailing wind in the opposite direction, so giving the potential to drift in one direction and sail in the other. Many do not consider sails to have been used before

3366-433: Is very little stress at the tack, whereas head sails (spinnakers and jibs) are more likely to be tri-radial, because they are tensioned at their corners. Higher performance sails may be laminated, constructed directly from multiple plies of filaments , fibers , taffetas , and films , instead of woven textiles that are adhered together. Molded sails are laminated sails formed over a curved mold and adhered together into

3468-474: 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 scheduled services that ran at higher average speeds than sailing vessels. Large improvements in fuel economy allowed steam to progressively outcompete sail in, ultimately, all commercial situations, giving ship-owning investors

3570-470: The River Tyne to London – which was already being carried out in the 14th century and grew as the city increased in size. In 1795, 4,395 cargoes of coal were delivered to London. This would have needed a fleet of about 500 sailing colliers (making 8 or 9 trips a year). This quantity had doubled by 1839. (The first steam-powered collier was not launched until 1852 and sailing colliers continued working into

3672-564: The caravel in Northern European waters from about 1440 made lateen sails familiar in this part of the world. Additionally, lateen sails were used for the mizzen on early three-masted ships, playing a significant role in the development of the full-rigged ship . It did not, however, provide much of the propulsive force of these vessels – rather serving as a balancing sail that was needed for some manoeuvres in some sea and wind conditions. The extensive amount of contemporary maritime art showing

3774-399: The linear mass density of fibers). Cross-cut sails have the panels sewn parallel to one another, often parallel to the foot of the sail, and are the least expensive of the two sail constructions. Triangular cross-cut sail panels are designed to meet the mast and stay at an angle from either the warp or the weft (on the bias ) to allow stretching along the luff, but minimize stretching on

3876-409: The motive power for sailing craft. The waves give an indication of the true wind direction. The flag gives an indication of apparent wind direction. True wind velocity ( V T ) combines with the sailing craft's velocity ( V B ) to give the apparent wind velocity ( V A ), the air velocity experienced by instrumentation or crew on a moving sailing craft. Apparent wind velocity provides

3978-500: The saildrones completed the mission, traveling 12,500 miles (20,100 km) over the seven month journey while collecting a detailed data set using on board environmental monitoring instrumentation. In August 2019, SD 1021 completed the fastest unmanned Atlantic crossing sailing from Bermuda to the UK, and in October, it completed the return trip to become the first autonomous vehicle to cross

4080-504: The 11th into the 19th centuries. Materials used in sails, as of the 21st century, include nylon for spinnakers, where light weight and elastic resistance to shock load are valued and a range of fibers, used for triangular sails, that includes Dacron , aramid fibers including Kevlar , and other liquid crystal polymer fibers including Vectran . Woven materials, like Dacron, may specified as either high or low tenacity , as indicated, in part by their denier count (a unit of measure for

4182-424: The 1870s to 1900, when steamships began to outpace them economically because of their ability to keep a schedule regardless of the wind. Steel hulls also replaced iron hulls at around the same time. Even into the twentieth century, sailing ships could hold their own on transoceanic voyages such as Australia to Europe, since they did not require bunkerage for coal nor fresh water for steam, and they were faster than

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4284-428: The 20th century.) The earliest image suggesting the use of sail on a boat may be on a piece of pottery from Mesopotamia , dated to the 6th millennium BCE. The image is thought to show a bipod mast mounted on the hull of a reed boat – no sail is depicted. The earliest representation of a sail, from Egypt, is dated to circa 3100 BCE. The Nile is considered a suitable place for early use of sail for propulsion. This

4386-599: The 5th millennium BCE. Others consider sails to have been invented much earlier. Archaeological studies of the Cucuteni-Trypillian culture ceramics show use of sailing boats from the sixth millennium BCE onwards. Excavations of the Ubaid period (c. 6000–4300 BCE) in Mesopotamia provide direct evidence of sailing boats. Sails from ancient Egypt are depicted around 3200 BCE, where reed boats sailed upstream against

4488-622: The Age of Discovery, sailing ships figured in European voyages around Africa to China and Japan; and across the Atlantic Ocean to North and South America. Later, sailing ships ventured into the Arctic to explore northern sea routes and assess natural resources. In the 18th and 19th centuries sailing vessels made Hydrographic surveys to develop charts for navigation and, at times, carried scientists aboard as with

4590-591: The Atlantic in both directions. The University of Washington and the Saildrone company began a joint venture in 2019 called The Saildrone Pacific Sentinel Experiment, which positioned six saildrones along the west coast of the United States to gather atmospheric and ocean data. A sailing craft's ability to derive power from the wind depends on the point of sail it is on—the direction of travel under sail in relation to

4692-468: The Austronesians, these distinctive characteristics must have been developed at or some time after the beginning of the expansion. They traveled vast distances of open ocean in outrigger canoes using navigation methods such as stick charts . The windward sailing capability of Austronesian boats allowed a strategy of sailing to windward on a voyage of exploration, with a return downwind either to report

4794-518: The McKinley mooring basin, the harbor behind Milwaukee's break wall, and for sailors who demonstrate proficiency and earn appropriate ratings and endorsements, Milwaukee Bay to one mile off the breakwall. The fleet at the Milwaukee Community Sailing Center includes 35 22-foot (6.7 m) Pearson Ensigns , 7 J-24s , 4 Solings and two larger cruising sailboats (a C&C 29 and a Catalina 27). Youth and adults aspiring to centerboard sailing will experience

4896-569: The River Nile 's current. Ancient Sumerians used square rigged sailing boats at about the same time, and it is believed they established sea trading routes as far away as the Indus valley . Greeks and Phoenicians began trading by ship by around 1200 BCE. V-shaped square rigs with two spars that come together at the hull were the ancestral sailing rig of the Austronesian peoples before they developed

4998-414: The Sailing Center has put together to provide services for the needs of those interested in the joys and benefits of sailing. 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 , windsurfer , or kitesurfer ), on ice ( iceboat ) or on land ( land yacht ) over a chosen course , which

5100-411: The Sailing Center offers three course levels; Basic, Intermediate and Advanced. The Milwaukee Community Sailing Center has a variety of outreach programs that provide access to Lake Michigan through sailing and water safety training. Through coordinated efforts with many community service organizations, the Sailing Center is able to provide experiences to many individuals. The following are programs that

5202-488: The angle of a fore-and-aft sail with respect to the apparent wind is controlled with a line, called a "sheet". On points of sail between close-hauled and a broad reach, the goal is typically to create flow along the sail to maximize power through lift. Streamers placed on the surface of the sail, called tell-tales , indicate whether that flow is smooth or turbulent. Smooth flow on both sides indicates proper trim. A jib and mainsail are typically configured to be adjusted to create

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5304-412: The availability, strength and direction of the wind is key to using its power along the desired course. Ocean currents, tides and river currents may deflect a sailing vessel from its desired course. If the desired course is within the no-go zone, then the sailing craft must follow a zig-zag route into the wind to reach its waypoint or destination. Downwind, certain high-performance sailing craft can reach

5406-400: The boat for the night, and cruising, where one stays aboard. Day-sailing primarily affords experiencing the pleasure of sailing a boat. No destination is required. It is an opportunity to share the experience with others. A variety of boats with no overnight accommodations, ranging in size from 10 feet (3.0 m) to over 30 feet (9.1 m), may be regarded as day sailors. Cruising on

5508-623: The course. This combination of forces means that it is possible to sail an upwind course as well as downwind. The course with respect to the true wind direction (as would be indicated by a stationary flag) is called a point of sail . Conventional sailing craft cannot derive wind power on a course with a point of sail that is too close into the wind. Throughout history, sailing was a key form of propulsion that allowed for greater mobility than travel over land. This greater mobility increased capacity for exploration, trade, transport, warfare, and fishing, especially when compared to overland options. Until

5610-479: The delivery by sailing ships of the large amounts of grain needed. It has been estimated that it cost less for a sailing ship of the Roman Empire to carry grain the length of the Mediterranean than to move the same amount 15 miles by road. Rome consumed about 150,000 tons of Egyptian grain each year over the first three centuries AD. A similar but more recent trade, in coal, was from the mines situated close to

5712-411: The destination more quickly by following a zig-zag route on a series of broad reaches. Negotiating obstructions or a channel may also require a change of direction with respect to the wind, necessitating changing of tack with the wind on the opposite side of the craft, from before. Changing tack is called tacking when the wind crosses over the bow of the craft as it turns and jibing (or gybing ) if

5814-462: The early steamers, which usually could barely make 8 knots (15 km/h). Ultimately, the steamships' independence from the wind and their ability to take shorter routes, passing through the Suez and Panama Canals , made sailing ships uneconomical. Until the general adoption of carvel -built ships that relied on an internal skeleton structure to bear the weight of the ship and for gun ports to be cut in

5916-408: The fleet during Open Sailing. Members are allowed to bring guests to sail and are able to participate in the Sailing Center's racing program. Members participate in social events, take advantage of the Sailing Center's grounds, which provide volleyball courts and a picnic area, meet new people and have a great time, which is what being a member of the Sailing Center is all about. For adults and youth,

6018-444: The force component in the direction of the apparent wind and lift , the force component normal (90°) to the apparent wind. Depending on the alignment of the sail with the apparent wind, lift or drag may be the predominant propulsive component. Total aerodynamic force also resolves into a forward, propulsive, driving force, resisted by the medium through or over which the craft is passing (e.g., through water, air, or over ice, sand) and

6120-440: The fore-and-aft crab claw , tanja and junk rigs . The date of introduction of these later Austronesian sails is disputed. Lateen sails emerged by around the 2nd century CE in the Mediterranean. They did not become common until the 5th century, when there is evidence that the Mediterranean square sail (which had been in wide use throughout the classical period ) was undergoing a simplification of its rigging components. Both

6222-404: The free end points into the eye of the wind and must be controlled to avoid a violent change to the other side; square rigs as they present the full area of the sail to the wind from the rear experience little change of operation from one tack to the other; and windsurfers again have flexibly pivoting and fully rotating masts that get flipped from side to side. Winds and oceanic currents are both

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6324-447: The full frontal area of the sail to the wind, when changing from side to side; and windsurfers have flexibly pivoting and fully rotating masts that get flipped from side to side. A sailing craft can travel directly downwind only at a speed that is less than the wind speed. However, some sailing craft such as iceboats , sand yachts , and some high-performance sailboats can achieve a higher downwind velocity made good by traveling on

6426-518: The heeling moment and keeping the boat more upright. There are three common methods of reefing the mainsail: 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

6528-423: The hull's resistance to heeling, yawing or progress through the water. In their most developed version, square sails are controlled by two each of: sheets, braces, clewlines , and reef tackles, plus four buntlines , each of which may be controlled by a crew member as the sail is adjusted. Towards the end of the Age of Sail, steam-powered machinery reduced the number of crew required to trim sail. Adjustment of

6630-480: The increasing popularity of the lateen and the changes to the contemporary square rig are suggested to be cost saving measures, reducing the number of expensive components needed to fit out a ship. It has been a common and erroneous presumption among maritime historians that lateen had significantly better sailing performance than the square rig of the same period. Analysis of voyages described in contemporary accounts and also in various replica vessels demonstrates that

6732-432: The islands of Maritime Southeast Asia , then later sailed further onwards to Micronesia , Island Melanesia , Polynesia , and Madagascar , eventually settling a territory spanning half the globe. The proto- Austronesian words for sail, lay(r) , and some other rigging parts date to about 3000 BCE when this group began their Pacific expansion. Austronesian rigs are distinctive in that they have spars supporting both

6834-430: The lake, year-round boat and dinghy storage, mast stepping boat launching and haul out services. Each summer the Sailing Center partners with local organizations to provide sailing opportunities to thousands of at-risk and economically disadvantaged youth, the physically challenged and others. The Sailing Center also provides social activities and volunteer opportunities to members. The Milwaukee Community Sailing Center

6936-454: The lateen mizzen on 16th and 17th century ships often has the sail furled. Practical experience on the Duyfken replica confirmed the role of the lateen mizzen. Austronesian invention of catamarans , outriggers , and the bi-sparred triangular crab claw sails enabled their ships to sail for vast distances in open ocean. It led to the Austronesian Expansion . From Taiwan, they rapidly settled

7038-401: The lateen. The lines can be categorized as those that support the sail, those that shape it, and those that control its angle to the wind. Fore-and-aft rigged vessels have rigging that supports, shapes, and adjusts the sails to optimize their performance in the wind, which include the following lines: Square-rigged vessels require more controlling lines than fore-and-aft rigged ones, including

7140-422: The luff and foot, where the fibers are aligned with the edges of the sail. Radial sails have panels that "radiate" from corners in order to efficiently transmit stress and are typically of higher performance than cross-cut sails. A bi-radial sail has panels radiating from two of three corners; a tri-radial sail has panels radiating from all three corners. Mainsails are more likely to be bi-radial, since there

7242-402: The mid 19th century. Sail plans with just fore-and-aft sails ( schooners ), or a mixture of the two ( brigantines , barques and barquentines ) emerged. Coastal top-sail schooners with a crew as small as two managing the sail handling became an efficient way to carry bulk cargo, since only the fore-sails required tending while tacking and steam-driven machinery was often available for raising

7344-416: The motive power for the sails on any given point of sail. It varies from being the true wind velocity of a stopped craft in irons in the no-go zone, to being faster than the true wind speed as the sailing craft's velocity adds to the true windspeed on a reach. It diminishes towards zero for a craft sailing dead downwind. Sailing craft A is close-hauled. Sailing craft B is on a beam reach. Sailing craft C

7446-408: The myth that sailing is an elitist sport. With seed money from Ted Seaver, Doug Drake, and Milwaukee County, a maintenance facility was built. Completed in 1980, and the Sailing Center opened with lessons and boat rentals with a seasonal staff of 10 and a small fleet of Tech Dinghies, Volants and a safety boat. Twelve students graduated from sailing courses in the first year and gained access to sail

7548-475: The neolithic lifestyle or the first establishment of cities. Yet it is not known when or where this invention took place. Much of the early development of water transport is believed to have occurred in two main "nursery" areas of the world: Island Southeast Asia and the Mediterranean region. In both of these you have warmer waters, so that use of rafts is possible without the risk of hypothermia (a raft

7650-576: The performance of square rig and lateen were very similar. Lateen provided a cheaper rig to build and maintain, with no degradation of performance. The lateen was adopted by Arab seafarers (usually in the sub-type: the settee sail ), but the date is uncertain, with no firm evidence for their use in the Western Indian Ocean before 1500 CE. There is, however, good iconographic evidence of square sails being used by Arab, Persian and Indian ships in this region in, for instance, 1519. The popularity of

7752-531: The rest of Austronesia , crab claw sails were mainly for double-outrigger ( trimarans ) and double-hulled ( catamarans ) boats, which remained stable even leeward. In western Island Southeast Asia , later square sails also evolved from the crab claw sail, the tanja and the junk rig , both of which retained the Austronesian characteristic of having more than one spar supporting the sail. Aerodynamic forces on sails depend on wind speed and direction and

7854-416: The result of the sun powering their respective fluid media. Wind powers the sailing craft and the ocean bears the craft on its course, as currents may alter the course of a sailing vessel on the ocean or a river. Trimming refers to adjusting the lines that control sails, including the sheets that control angle of the sails with respect to the wind, the halyards that raise and tighten the sail, and to adjusting

7956-443: The sail cloth. There are several key factors in evaluating a fiber for suitability in weaving a sail-cloth: initial modulus , breaking strength (tenacity) , creep , and flex strength . Both the initial cost and its durability of the material define its cost-effectiveness over time. Traditionally, sails were made from flax or cotton canvas , although Scandinavian, Scottish and Icelandic cultures used woolen sails from

8058-404: The sailing ships during this time period were the merchant ships. By 1500, Gun ports allowed sailing vessels to sail alongside an enemy vessel and fire a broadside of multiple cannon. This development allowed for naval fleets to array themselves into a line of battle , whereby, warships would maintain their place in the line to engage the enemy in a parallel or perpendicular line. While

8160-459: The sails and the anchor. Iron-hulled sailing ships represented the final evolution of sailing ships at the end of the Age of Sail. They were built to carry bulk cargo for long distances in the nineteenth and early twentieth centuries. They were the largest of merchant sailing ships, with three to five masts and square sails, as well as other sail plans . They carried bulk cargoes between continents. Iron-hulled sailing ships were mainly built from

8262-413: The shape of the boat, especially with a catamaran. As the boat points off the wind, lateral force and the forces required to resist it become less important. On ice boats, lateral forces are countered by the lateral resistance of the blades on ice and their distance apart, which generally prevents heeling. Wind and currents are important factors to plan on for both offshore and inshore sailing. Predicting

8364-614: The shape of the sail, notably the outhaul , halyard , boom vang and backstay . These control the curvature that is appropriate to the windspeed, the higher the wind, the flatter the sail. When the wind strength is greater than these adjustments can accommodate to prevent overpowering the sailing craft, then reducing sail area through reefing , substituting a smaller sail or by other means. Reducing sail on square-rigged ships could be accomplished by exposing less of each sail, by tying it off higher up with reefing points. Additionally, as winds get stronger, sails can be furled or removed from

8466-556: The shared fleet. In the summer of 2023, MCSC offered over 1200 instructional sessions and members sailed almost 7000 times. In 1985, MCSC began "Prams in the Park", a program designed to bring sailing and water safety kids from 8-11 years old in Milwaukee County Park lagoons. Today, MCSC offers entry-level, intermediate and advanced sailing instruction, regattas, expeditions, volunteer instructor opportunities and open sailing seven days

8568-440: The side, sailing ships were just vehicles for delivering fighters to the enemy for engagement. Early Phoenician, Greek, Roman galleys would ram each other, then pour onto the decks of the opposing force and continue the fight by hand, meaning that these galleys required speed and maneuverability. This need for speed translated into longer ships with multiple rows of oars along the sides, known as biremes and triremes . Typically,

8670-444: The significant improvements in land transportation that occurred during the 19th century, if water transport was an option, it was faster, cheaper and safer than making the same journey by land. This applied equally to sea crossings, coastal voyages and use of rivers and lakes. Examples of the consequences of this include the large grain trade in the Mediterranean during the classical period . Cities such as Rome were totally reliant on

8772-402: The spars, entirely until the vessel is surviving hurricane-force winds under "bare poles". On fore-and-aft rigged vessels, reducing sail may furling the jib and by reefing or partially lowering the mainsail, that is reducing the area of a sail without actually changing it for a smaller sail. This results both in a reduced sail area but also in a lower centre of effort from the sails, reducing

8874-445: 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 ( V A ), the wind speed and direction as measured on the moving craft. The apparent wind on the sail creates a total aerodynamic force, which may be resolved into drag ,

8976-434: The speed between the starting and ending points of the route is called the speed made good and is calculated by the distance between the two points, divided by the travel time. The limiting line to the waypoint that allows the sailing vessel to leave it to leeward is called the layline . Whereas some Bermuda-rigged sailing yachts can sail as close as 30° to the wind, most 20th-Century square riggers are limited to 60° off

9078-551: The surface, a sail can propel a craft to a higher speed, on points of sail when the entry point of the sail is aligned with the apparent wind, than it can with the entry point not aligned, because of a combination of the diminished force from airflow around the sail and the diminished apparent wind from the velocity of the craft. Because of limitations on speed through the water, displacement sailboats generally derive power from sails generating lift on points of sail that include close-hauled through broad reach (approximately 40° to 135° off

9180-416: 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, the arc spanning 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 "close-hauled". At 90° off

9282-539: The upper and lower edges of the sails (and sometimes in between). The sails were also made from salt-resistant woven leaves, usually from pandan plants. Crab claw sails used with single-outrigger ships in Micronesia , Island Melanesia , Polynesia , and Madagascar were intrinsically unstable when tacking leeward. To deal with this, Austronesians in these regions developed the shunting technique in sailing, in conjunction with uniquely reversible single-outriggers. In

9384-427: The use of sailing vessels for commerce or naval power has been supplanted with engine-driven vessels, there continue to be commercial operations that take passengers on sailing cruises. Modern navies also employ sailing vessels to train cadets in seamanship . Recreation or sport accounts for the bulk of sailing in modern boats. Recreational sailing can be divided into two categories, day-sailing, where one gets off

9486-639: The various combinations of sail proposed for a sailing ship . Sail plans may vary for different wind conditions—light to heavy. Both square-rigged and fore-and-aft rigged vessels have been built with a wide range of configurations for single and multiple masts with sails and with a variety of means of primary attachment to the craft, including: High-performance yachts, including the International C-Class Catamaran , have used or use rigid wing sails , which perform better than traditional soft sails but are more difficult to manage. A rigid wing sail

9588-675: The voyages of James Cook and the Second voyage of HMS Beagle with naturalist Charles Darwin . In the early 1800s, fast blockade-running schooners and brigantines— Baltimore Clippers —evolved into three-masted, typically ship-rigged sailing vessels with fine lines that enhanced speed, but lessened capacity for high-value cargo, like tea from China. Masts were as high as 100 feet (30 m) and were able to achieve speeds of 19 knots (35 km/h), allowing for passages of up to 465 nautical miles (861 km) per 24 hours. Clippers yielded to bulkier, slower vessels, which became economically competitive in

9690-406: 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 passes along its surface, just as an airplane wing generates lift , which predominates over aerodynamic drag retarding forward motion. The more that the angle of attack diverges from the apparent wind as

9792-402: The wind passes over the stern. A sailing craft can sail on a course anywhere outside of its no-go zone. If the next waypoint or destination is within the arc defined by the no-go zone from the craft's current position, then it must perform a series of tacking maneuvers to get there on a zigzag route, called beating to windward . The progress along that route is called the course made good ;

9894-405: The wind). Because of low friction over the surface and high speeds over the ice that create high apparent wind speeds for most points of sail, iceboats can derive power from lift further off the wind than displacement boats. Each rig is configured in a sail plan , appropriate to the size of the sailing craft. A sail plan is a set of drawings, usually prepared by a naval architect which shows

9996-419: The wind, a craft is on a "beam 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". In points of sail that range from close-hauled to a broad reach, sails act substantially like a wing, with lift predominantly propelling the craft. In points of sail from a broad reach to down wind, sails act substantially like

10098-540: The wind. Fore-and-aft rigs are designed to operate with the wind on either side, whereas square rigs and kites are designed to have the wind come from one side of the sail only. Because the lateral wind forces are highest when sailing close-hauled, the resisting water forces around the vessel's keel, centerboard, rudder and other foils must also be highest in order to limit sideways motion or leeway . Ice boats and land yachts minimize lateral motion with resistance from their blades or wheels. Tacking or coming about

10200-673: The world. Circular routes exist between the Americas and Europe, and between South Africa and South America. There are many routes from the Americas, Australia, New Zealand, and Asia to island destinations in the South Pacific. Some cruisers circumnavigate the globe. Sailing as a sport is organized on a hierarchical basis, starting at the yacht club level and reaching up into national and international federations; it may entail racing yachts , sailing dinghies , or other small, open sailing craft, including iceboats and land yachts. Sailboat racing

10302-471: Was invented by Richard Jenkins , a British engineer, founder and CEO of Saildrone, Inc. Saildrones have been used by scientists and research organizations like the National Oceanic and Atmospheric Administration (NOAA) to survey the marine ecosystem, fisheries, and weather. In January 2019, a small fleet of saildrones was launched to attempt the first autonomous circumnavigation of Antarctica. One of

10404-424: Was used by Stars and Stripes , the defender which won the 1988 America's Cup , and by USA-17 , the challenger which won the 2010 America's Cup . USA 17' s performance during the 2010 America's Cup races demonstrated a velocity made good upwind of over twice the wind speed and downwind of over 2.5 times the wind speed and the ability to sail as close as 20 degrees off the apparent wind. The shape of

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