Information AboutSailing |
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Sailing is the skillful art of controlling the motion of a Sailing Ship or smaller Boat , across a body of water. Sailing vessels are propelled by the force of the Wind on Sails . Today, for most people, sailing is recreation, an activity pursued for the joy of being on the water and pursuing the mastery of the skills needed to maneuver a sailboat in varying sea and wind conditions. Recreational sailing can be further divided into Racing , Cruising and "Daysailing." Introduction A boat moves as wind pushes on its sails. This is obvious when the boat is sailing downwind. The keel of a boat keeps it from strafing to the sides. This allows a boat to sail downwind but at an angle. The wind that blows on a sail is deflected off the sail, and that wind pushes against the sail too. The result is that the sail is not just pushed straight downwind, no matter which way it faces; but rather, it is pushed in the direction that it bows. This lets a boat point upwind, though at an angle and not straight upwind, to move forward as long as the sail is able to bow forward. If the sail is pointed just as the boat, then the boat will only be pushed sideways, yet if the sail is pointed into the wind, then it will not catch the wind at all. So, the sail must be pointed somewhere between.
When sailing downwind, a boat catches up to the wind, so the wind cannot push as hard on the sails. When sailing at an angle to the wind, however, although the boat may move fast, it is not catching up to the wind, so the wind continues to push the boat faster. Of course, eventually the boat cannot move faster because of the water, but not before speeding along much faster than if it had been sailing directly downwind.
The physics of sailing The force of the wind is used to create motion by using one or more sails. When sailing downwind (away from the wind source) the vessel's motion is derived from the simple force of the wind pushing the sail. When sailing upwind (towards the wind source) the movement of air over the sails acts in the same way as air moving over an aircraft's wing. Air flowing over the sail generates lift. This pulls the sail (and the boat) ahead, but also pushes it downwind rather strongly. The downwind, or leeward, component is offset by an underwater Hydrofoil whose shape resists lateral movement while offering little resistance to forward motion. Some hydrofoils even convert some of the leeward movement into forward motion. Without this hydrofoil, sailing upwind or across the wind would be virtually impossible. Sailing hydrofoils include Keels , centerboards, and particularly in small sailboats the rudder acts as a hydrofoil also, reducing leeway. The lifting force of the sails also acts to lean the boat over to one side, which is called heeling. Heeling is counteracted by ballast, either in the form of dense material located deep in the bilge or externally in the keel, usually lead or iron. In ancient times ships used following or rear-quarter winds. Therefore, they had to either row or wait in port or at sea for the right wind directions. Basic sailing techniques The article Points Of Sail defines several terms that identify a sailboat's movement relative to the wind direction. Steering and turning When steering a sailboat, the method for changing direction depends on the direction of the wind. Thus, all direction changes or turns are described by one of the following terms:
Trim An important aspect of sailing is keeping the boat in " Trim ". To achieve this a useful Mnemonic (memory aid) is the phrase: '' Can '''T'''his '''B'''oat '''S'''ail Correctly? '' This helps the crew to remember these essential points;
Running running downwind with a Spinnaker .]] Sailing the boat within roughly 30 degrees either side of dead downwind is called a run. This is the easiest point of sail in terms of comfort, but it can also be the most dangerous. When sailing upwind, it's easy to stop the boat by heading into the Wind , a sailor has no such easy out when running. Severe rolling is more likely as there is less rolling resistance provided by the sails, which are eased out. And loss of attention by the helmsman could lead the boat to Jibe accidentally, causing injury to the boat or crew. It's always a good idea to use a Preventer to prevent an accidental jibe. Alternately, if there is a sudden increase in wind strength, the boat can round up very suddenly and heel excessively, often leading to a capsize in smaller boats. This is called Broaching . Reaching When the boat is traveling approximately perpendicular to the wind, this is called reaching. A 'close' reach is somewhat toward the wind, and 'broad' reach is a little bit away from the wind (a 'beam' reach is with the wind precisely at right angles to the boat). For most modern sailboats, reaching is the fastest way to travel. Sailing upwind A basic rule of sailing is that it is not possible to sail directly into the wind. Generally speaking, a boat can sail 45 degrees off the wind. When a boat is sailing this close to the wind, it is close-hauled or beating (beating to weather). Since a boat cannot sail directly into the wind, but the destination is often upwind, one can only get there by sailing close-hauled with the wind coming from the port side (the boat is on port tack), then Tack ing (turning the boat through the eye of the wind) and sailing with the wind coming from the starboard side (the boat is on starboard tack). By this method, it is possible to reach that destination directly upwind. The heavier the wind, the rougher the seas, thus boat movement can be more uncomfortable. This can feel like the boat is beating its hull into the waves, hence the term beating. How close a boat can sail to the wind depends on the boat's design, sail trim, the sea state and the Wind Speed , since what the boat "sees" is the Apparent Wind , i.e., the Vector Sum of the actual wind and the boat's own velocity. The apparent wind speed is what the Anemometer on top of the mast shows. A good analogy to this would be walking through an indoor room and feeling the "wind" on your face. The faster you walk, the more wind your feel. The apparent wind angle while sailing close hauled will be less than the true wind angle. A good, modern sloop can sail within 25 degrees of the apparent wind. An America's Cup racing sloop can sail within 16 degrees, under the right conditions. Those figures might translate into 45 degrees and 36 degrees relative to the actual wind, depending on boat speed. Reducing sail An important safety aspect of sailing is to adjust the amount of sail to suit the wind conditions. As the wind speed increases the crew should progressively reduce the amount of sail. On a small boat with only jib and mainsail this is done by Furling the jib and by partially lowering the mainsail, a process called 'reefing the main'. Reefing means reducing the area of a sail without actually changing it for a smaller sail. Ideally reefing does not only result in a reduced sail area but also in a lower center of effort from the sails, reducing the heeling moment and keeping the boat more upright. There are three common methods of reefing the mainsail:
Mainsail furling systems have become increasingly popular on cruising yachts as they can be operated shorthanded and from the cockpit in most cases, however, the sail can become jammed in the Mast or boom slot if not operated correctly. Mainsail furling is almost never used while racing because it results in a less efficient sail profile. The classical slab-reefing method is the most widely used. Mainsail furling has an additional disadvantage in that its complicated gear may somewhat increase weight aloft. However, as the size of the boat increases, the benefits of mainsail roller furling increase dramatically. Sail trimming As noted above, sail Trim ming is a large subject. Basic control of the mainsail consists of setting the sail so that it is at an optimum angle to the wind, (i.e. no flapping at the front, and tell tales flowing evenly off the rear of the sail). Two or more sails are frequently combined to maximise the smooth flow of Air . The sails are adjusted to create a smooth laminar flow over the sail surfaces. This is called the "slot effect". The combined sails fit into an imaginary aerofoil outline, so that the most forward sails are more in line with the wind, whereas the more aft sails are more in line with the course followed. The combined efficiency of this sail plan is greater than the sum of each sail used in isolation. More detailed aspects include specific control of the sail's shape, e.g.:
Heeling When a boat rolls over to one side under wind pressure, it's called 'heeling'. As a sailing boat heels over beyond a certain angle, it begins to sail less efficiently. Several forces can counteract this movement. in round Anglesey race 1998 ]]
Most of the above effects can be used to right a heeling boat and to keep the boat sailing efficiently: if however the boat heels beyond a certain point of stability, it can capsize. A boat is said to have capsized when the tip of the mast is in the water. Sailing safety First and foremost: # Stay on the boat! # Wear a life vest! # Learn to swim! Sailing requires respect for the risks of being on the water. All sailors therefore should be sensibly prepared. Most jurisdictions have certain minimum regulations that must be met as to equipment. When engaged in publicly organized activities they may be required to take additional precautions, as detailed by the authority which regulates the training or racing. Safety measures may include:
Aside from what may be required by law or a sailing organization, real safety on the water comes from an informed awareness of risks involved and the exercise of reasonable steps to avoid dangers.
Also, know the 'rules of the road':
Sailing hulls and hull shapes ]] Sailing boats can have one, two, or three Hull s. Boats with one hull are known as monohulls, while those with two or more are known as Multihull s. Multihulls can be further subdivided into Catamaran s (two hulls), and Trimaran s (three hulls). A sailing boat is turned by a Rudder which itself is controlled by a Tiller or a wheel. Smaller sailing boats often have a stabilising, raisable, underwater fin called a centreboard (or daggerboard); larger sailing boats have a fixed (or sometimes canting) Keel . As a general rule, the former are called dinghies, the latter yachts. However, up until the adoption of the Racing Rules Of Sailing , any vessel racing under sail was considered a yacht, be it a multi-masted ship-rigged vessel (such as a sailing frigate), a sailboard (more commonly referred to as a Windsurfer ) or remote-controlled boat, or anything in between. (see Dinghy Sailing ) Multihulls use flotation and/or weight positioned away from the centre line of the sailboat to counter the force of the wind. This is in contrast to heavy ballast that can make up to 1/3 of the weight of a monohulled sailboat. In the case of a standard catamaran there are two similarly sized and shaped narrow hulls connected by beams which are sometimes overlaid by a deck superstructure. Another catamaran variation is the Proa . In the case of trimarans, which have an unballasted centre hull similar to a monohull, two relatively smaller Ama s are situated parallel to the centre hull to resist the sideways force of the wind. The advantage of multihulled sailboats is that they do not suffer the performance penalty of having to carry heavy ballast, and their relatively smaller hulls reduce the amount of drag caused by friction and inertia when moving through the water. Types of sails and layouts A traditional modern yacht is technically called a " Bermuda Sloop " (sometimes a "Bermudan sloop"). A sloop is any boat that has only a single mast. The Bermuda designation refers to the fact that the sail which has its forward edge (the "luff") against the mast (the main sail) is a sail roughly triangular in shape. Addionally, Bermuda sloops only have a single sail behind the mast. Other types of sloops are gaff-rigged sloops and Lateen sloops (sometimes called a junk-rig). Gaff-rigged sloops have quadrilateral mainsails with a Gaff (a small boom) at their upper edge (the "head" of the sail). Gaff-rigged vessels may also have another sail, called a topsail, above the gaff. Lateen sloops have triangular sails with the upper edge attached to a gaff, and the lower edge attached to the boom, and the boom and gaff are attached to each other via some type of hinge. It is also possible for a sloop to be square rigged (having large square sails like a Napoleonic Wars -era Ship Of The Line ). Note that a " Sloop Of War ," in the naval sense, may well have more than one mast, and is not properly a sloop by the modern meaning. If a boat has two masts, it may be either a Schooner , a Ketch , or a Yawl , if it is rigged fore-and-aft on all masts. A schooner may have any number of masts provided the second from the front is the tallest (called the "main mast"). In both a ketch and a yawl, the foremost mast is tallest, and thus the main mast, while the rear mast is shorter, and called the mizzen mast. The difference between a ketch and a yawl is that in a ketch, the mizzen mast is forward of the rudderpost (the axis of rotation for the rudder), while a yawl has its mizzen mast behind the rudderpost. In modern parlance, a Brigantine is a vessel whose forward mast is rigged with square sails, while her after mast is rigged fore-and-aft. A Brig is a vessel with two masts both rigged square. As one gets into three or more masts the number of combinations rises and one gets Barque s, Barquentine s, and three-masted Brig s. A Spinnaker is a large, full sail that is only used when sailing off wind either reaching or downwind, to catch the maximum amount of wind. See also Sail and Sail-plan . Sailing terminology Sailors use many traditional nautical terms for the parts of or directions on a vessel; Starboard (right), Port (left), forward or fore (front), aft (rearward), bow (forward part of the hull), stern (aft part of the hull), beam (the widest part). Vertical spars are masts, horizontal spars are booms (if they can hit you), gaffs (if they're too high to reach) or poles (if they can't hit you). Rope and lines ''Rope'' is the term used only for raw material; once a section of rope is designated for a particular purpose on a vessel, it generally is called a ''line,'' as in ''outhaul line'' or ''dock line''. A very thick line is considered a ''cable.'' Lines that are attached to sails to control their shapes are called ''sheets'', as in ''mainsheet'' (line that controls the mainsail) or ''spinnaker sheets.'' Lines (generally steel cables) that support masts are stationary and are collectively known as a vessel's Standing Rigging , and individually as ''shrouds'' or ''stays'' (the stay running forward from a mast to the bow is called the ''forestay'' or ''headstay''). Moveable lines that control sails or other equipment are known collectively as a vessel's Running Rigging . Lines that raise sails are called '' Halyards '' while those that strike them are called ''downhauls'' or ''cunninghams''. Lines that adjust (trim) the sails are called ''sheets'' . These are often referred to using the name of the sail they control (such as ''main sheet'', or ''jib sheet''). Sail trim may also be controlled with smaller lines attached to the forward section of a boom; such a line is called a ''vang'', or a ''kicker'' in the United Kingdom. Lines used to tie a boat up when alongside are called ''docklines'', ''docking cables'' or ''mooring warps''. Some lines are referred to as ropes: A bell rope (to ring the bell), a bolt rope (attached to the edge of a sail for extra strength), a foot rope (on old square riggers for the sailors to stand on while reefing or furling the sails), and a tiller rope (to temporarily hold the tiller and keep the boat on course). A ''rode'' is what keeps an anchor attached to the boat when the anchor is in use. It may be chain, rope, or a combination of the two. Other terms Walls are called 'bulkheads' or 'ceilings', while the surfaces referred to as 'ceilings' on land are called 'overheads'. Floors are called 'soles' or 'decks'. The toilet is traditionally called the 'head', the kitchen is the 'galley'. In sailing lines are rarely tied off, they are almost always 'made fast' or 'belayed.' Sails in different sail plans have unchanging names, however. For the naming of sails, see Sail-plan . Sailing terms have entered popular language in many ways. "Broken up" was the fate of a ship that hit a "rocky point" or was simply no longer wanted. "Poop" refers to the aftermost deck of a ship, taken from "puppis" the Latin word for "stern". "Pooped" refers to a wave breaking over the stern and filling the cockpit with water. "In the doldrums" referred to being becalmed, windless, especially in the narrow band of hot windless water "the doldrums", near the equator. "Adrift" meant literally that a ship's anchor had come loose, and the ship was out of control near land and therefore in serious danger. "Keel-hauled and hung out to dry." was the rather nasty process of attaching a sailor to a rope, and drawing him under the sailboat while underway, and then hanging him from a yard-arm (under his shoulders usually, not by his neck), where officers and crew could mock him. This was a particularly unpleasant punishment; apart from the risk of drowning, the sailor would be lacerated by the barnacles on the ship's hull. Sailing regulations There are two very basic rules for avoiding a collision at sea: 1) Power gives way to sail 2) Port gives way to starboard. This second point means that boats who have their sails set for a breeze coming from the left hand side of the boat (port) must give way to boats that have their sails set for a breeze coming from the right side of the boat (starboard). If both boats have their sails set on the same side of the boat, then the boat closer to where the wind is coming from (the Windward boat) must give way to the Leeward boat. However there are many other rules besides and sailors are expected to know the essentials of boating safety which include;
Sailboat racing Sailboat racing ranges from single person Dinghy Racing to large boats with 10 or 20 crew and from small boats costing a few hundred dollars to multi-million dollar Americas Cup or Sydney To Hobart Yacht Race campaigns. The costs of participating in the high end large boat competitions make this type of sailing one of the most expensive sports in the world. However, there are relatively inexpensive ways to get involved in sailboat racing, such as at community sailing clubs, and in some relatively inexpensive dinghy and small catamaran classes. Under these conditions, sailboat racing can be comparable to or less expensive than sports such as golf and skiing. Sailboat racing is one of the few sports in which people of all ages can regularly compete with and against each other. Although most sailboat racing is done in sheltered coastal or inland waters, in terms of endurance and risk to life, ocean racing, from 100 mile races between two ports to around the world races such as the Volvo Ocean Race , the solo VELUX 5 Oceans Race and the non-stop solo Vendée Globe , rate as some of the most extreme and dangerous sporting events. Not only do participants compete for days with little rest, but an unexpected storm, a single equipment failure, or collision with an ice flow could result in the sailboat being disabled or sunk hundreds or thousands of miles from Search And Rescue . The sport of Sailboat racing is governed by the , which can be found on the ISAF web site. Sailing traditions and etiquette There are many more esoteric, etiquette rules, traditions, and customs that will demonstrate to others advanced knowledge of boating protocol. Fenders should be pulled up outside ports, the flag of the host country should be shown, a boat should fly the Yacht Ensign of its nation of registry, flags are to be taken down at night, boats are to be referred to as female, a boat should not be named twice, etc. See also
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