Sailing
From Wikipedia, the free encyclopedia
Sailing is the skillful art of controlling the motion of a sailing ship or sailboat, across a body of water. The force of the wind on the sails propels sailing vessels. Today, for most people, sailing is recreation, an activity pursued for the joy of being on the water and pursuing the mastery of skills needed to maneuver a sailboat in varying sea and wind conditions. Recreational sailing can be further divided into Racing, Cruising and "Daysailing" or Dinghy sailing.
Throughout history sailing has been instrumental in the development of civilization. The earliest representation of a ship under sail appears on an Egyptian vase from about 3500 BC.[1]
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[edit] Introduction
A sailboat or sailing ship moves forward because of the reaction to the inertia of moving air on its sails. Since the dawn of history this vital technology has afforded mankind greater mobility and capacity for fishing, trade and warfare. From moving the stones of the great pyramids from Aswan to Giza to allowing man to migrate throughout Polynesia to Nelson's defeat of the French Navy at the Battle of Trafalgar, mankind's history has been intertwined with this seemingly simple technology.
[edit] The physics of sailing
The energy that drives a sailboat is harnessed by manipulating the relative movement of wind and water speed; if there is no difference in movement, such as on a calm day or when the wind and water current are moving in the same direction, there is no energy to be extracted and the sailboat will not be able to do anything but drift. Where there is a difference in motion, then there is energy to be extracted at the interface, and the sailboat does this by placing the sail(s) in the air and the hull(s) in the water.
Sails are airfoils and work by using an airflow set up by the motion of the boat. This is the apparent wind, which is the relative velocity of the wind relative to the boats motion . They generate lift using the air that flows around them. The air flowing at the sail surface is not the true wind[2].
The sail alone is not sufficient to drive the boat in any desired direction, as a sail by itself would only to push a boat in the same direction as the wind. Sailboats overcome this by having another physical object below the water line. These include, a keel, centerboard, or some other form of underwater foil or even the hull itself (as in catamarans without centreboard or in a traditional proa). Thus, you could think of the physical portion of the boat which is below water as functioning as a "second sail". Having two surfaces against the wind and water enables the sailor to travel in almost any direction and to generate an additional source of lift from the water. The flow of water over the underwater hull portions creates a hydrodynamic force. The combination of the aerodynamic force from the sails and the hydrodynamic force from the underwater hull section allows motion in almost any direction, except straight into the wind. This can be likened, in simple terms, to squeezing a wet bar of soap with two hands which causes it to shoot out in a direction perpendicular to both opposing forces. Depending on the efficiency of the rig, the angle of travel relative to the true wind can be as little as 35 degrees to over 80 degrees. This angle is called tacking angle [2]. With a 35 degree tacking angle on either side of the wind, it is possible for a sailboat to sail directly over 290 degrees of the compass.[3]
When sailing upwind, the sails, when correctly adjusted, will generate aerodynamic lift. When sailing downwind, the sails no longer generate aerodynamic lift and airflow is stalled, with the wind push on the sails giving drag only. As the boat is going downwind, the apparent wind is less than the true wind and this allied to the fact that the sails are not producing aerodynamic lift serves to limit the downwind speed.[4]
When moving, the motion of the boat creates its own apparent wind. Apparent wind is what is experienced onboard and is the wind that the boat is actually sailing by. Sailing into the wind causes the apparent wind to be greater than the true wind and the direction of the apparent wind will be forward [5] of the true wind. Some extreme design boats are capable of traveling faster than the true windspeed.
Some non-traditional rigs purportedly capture energy from the wind in a much different fashion are capable of feats that traditional rigs are not, such as sailing dead into the wind. One such example is the wind turbine boat, also called the windmill boat[3][4], which uses a large windmill to extract energy from the wind, and a propeller to convert this energy to forward motion of the hull. A similar design, called the autogiro boat, uses a wind turbine without the propellor, and functions in a manner similar to a normal sail[5]. None of the above theoretical concepts have moved from paper concepts to physically existing boats on the water and the physics described must be carefully examined for accuracy.
[edit] Basic sailing techniques
The article Points of sail defines several terms that identify a sailboat's movement relative to the wind direction.
[edit] 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:
- Heading up (or luffing up) means steering so the wind is closer to coming from directly in front (or "on the bow"). Heading closer to the wind requires trimming the sails, pulling them towards the vessel's center. Heading up so the wind is nearly or directly ahead causes sails to luff, to flutter without achieving lift. If the boat loses maneuverability because of this, it is said to be in irons. Tacking (or coming about), one of the basic turning techniques, requires bringing the bow of the boat through the wind so that the wind then comes across the opposite side of the boat, and the boat sails away on the opposite tack.
- Heading down, bearing away, falling off and freeing off mean steering so the wind comes from closer to the vessel's aft. This requires easing sails, letting them out away from the vessel's center. Gybing or Jibing is the turning maneuver in which the boat heads down past the point where the wind crosses the vessel's stern, which causes the sails and boom to swing to the opposite side, before the boat sails off on the opposite tack. The sail and boom can cross the centerline of the boat with significant speed, and misjudged gybing can easily capsize a small boat, harm inattentive crew, or damage the rig in a larger boat, especially in strong winds.
[edit] Trim
An important aspect of sailing is keeping the boat in "trim". To achieve this a useful mnemonic (memory aid) is the phrase:
Can This Boat Sail Correctly?
This helps the crew to remember these essential points;
- Course to Steer - Turn the boat using the wheel or tiller to the desired course to steer. See points of sail. This may be a definite bearing (e.g steer 270 degrees), or towards a landmark, or at a desired angle to the apparent wind direction.
- Trim - This is the fore and aft balance of the boat. The aim is to adjust the moveable ballast (the crew!) forwards or backwards to achieve an 'even keel'. On an upwind course in a small boat, the crew typically sit forward, when 'running' it is more efficient for the crew to sit to the rear of the boat. The position of the crew matters less as the size (and weight) of the boat increases.
- Balance - This is the port and starboard balance. The aim, once again is to adjust weight 'inboard' or 'outboard' to prevent excessive heeling.
- Sail - Trimming sails is a large topic. Simply put however, a sail should be pulled in until it fills with wind, but no further than the point where the front edge of the sail (the luff) is exactly in line with the wind.
- Centreboard - If a moveable centreboard is fitted, then it should be lowered when sailing "close to the wind" but can be raised up on downwind courses to reduce drag. The centreboard prevents lateral motion and allows the boat to sail upwind. A boat with no centreboard will instead have a permanent keel, some other form of underwater foil, or even the hull itself which serves the same purpose.
Together, these points are known as 'The Five Essentials' and constitute the central aspects of sailing.
[edit] Running
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 gybe accidentally, causing injury to the boat or crew. (A preventer can be rigged to prevent damage from an accidental gybe.) 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.
[edit] Reaching
When the boat is traveling approximately perpendicular to the wind, this is called reaching. A 'close' reach is halfway between beating and a beam reach, and a '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, that is boats with triangular sails, reaching is the fastest way to travel. The direction of the wind is ideal for reaching because it will maximize the lift generated on the sails in the forward direction of the boat, giving the best boat speed. Also when reaching, the boat can be steered exactly in the direction that is most desirable, and the sails can be trimmed for that direction.
Reaching however may put the boat on a parallel course with the waves. When the waves are steep, it may be necessary to sail closer to the wind to avoid waves directly on the beam.
[edit] Sailing upwind
A basic rule of sailing is that it is not possible to sail directly into the wind—at least not for long. 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 tacking (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. For a yacht beating upwind to a mark at a distance upwind of one mile, it will cover a distance through the water of over 1.42 miles, if it can tack through an angle of 90 degrees. An old adage describes beating as sailing for twice[6] the distance at half the speed and three times the discomfort.
How closely a boat can sail into 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, the vector sum of the actual wind and the reciprocal[7] of 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 a room and feeling the "wind" on your face. The faster you walk, the more wind you 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 ideal conditions. Those figures might translate into 45 degrees and 36 degrees relative to the actual wind, depending on boat speed.
[edit] 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:
- Slab reefing, which involves lowering the sail by about one-quarter to one-third of its luff length and tightening the lower part of the sail using an outhaul or a pre-loaded reef line through a cringle at the new clew, and hook through a cringle at the new tack.
- In-mast (or on-mast) roller-reefing. This method rolls the sail up around a vertical foil either inside a slot in the mast, or affixed to the outside of the mast. It requires a mainsail with either no battens, or newly-developed vertical battens.
- In-boom roller-reefing, with a horizontal foil inside the boom. This method allows for standard- or full-length horizontal battens.
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.
Remember the old sea dog saying "the first time you think of reducing sail you should"
[edit] Sail trimming
As noted above, sail trimming 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.:
- reefing, or reducing the sail area in stronger wind
- altering sail shape to make it flatter in high winds
- raking the mast when going upwind (to tilt the sail towards the rear, this being more stable)
- providing sail twist to cope with gusty conditions
[edit] Hull Trim
Hull Trim is the adjustment of a boat's loading so as to change its fore-and-aft attitude in the water. In small boats, it is done by positioning the crew. In larger boats the weight of a person has less effect on the hull trim, but it can be adjusted by shifting gear, fuel, water, or supplies. Different hull trim efforts are required for different kinds of boats and different conditions. Here are just a few examples. In a lightweight racing dinghy like a Thistle, the hull should be kept level, on its designed water line for best performance in all conditions. In many small boats, weight too far aft can cause drag by submerging the transom, especially in light to moderate winds. Weight too far forward can cause the bow to dig into the waves. In heavy winds, a boat with its bow too low may capsize by pitching forward over its bow (pitch-pole) or dive under the waves (submarine). On a run in heavy winds, the forces on the sails tend to drive a boat's bow down, so the crew weight is moved far aft.
[edit] Points of Sail
The points of sail are the most important parts of sail theory to remember. The wind, or no go zone, is about 45° either side of the true wind, for a racing hull and sail plan optimized for upwind work. More commonly and on cruising sailplans, the best angle achievable upwind is 50° to 55° to the true wind. A boat cannot sail directly into the wind; attempting to do so is called luffing. There are 5 main points of sail. In order from the edge of the no go zone to directly downwind they are:
- close haul (22° to the apparent wind)
- close reach (half way between close hauled and a beam reach)
- beam reach (90° to the apparent wind)
- broad reach (22.5° away from directly downwind sailing)
- running (directly downwind)
The sail trim (and, on smaller boats, centre board/dagger board position) on a boat is relative to the point of sail you are on: on a beam reach sails are half way out, on a run sails are all the way out, and close hauled sails are pulled in very tightly. A large proportion of the skill of sailing is in trimming the sails correctly for direction and strength of the wind.
[edit] 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.
- The buoyancy of that part of the hull which is being submerged tends to bring the boat upright.
- Raising the centreboard can paradoxically increase leeway, and therefore reduce heeling.
- A weighted keel, which can in larger boats be canted from side to side, provides additional force to right the boat.
- The crew may move onto the high (upwind) side of the boat, called hiking, changing the centre of gravity significantly in a small boat. They can trapeze if the boat is designed for this (see Dinghy sailing).
- The underwater shape of the hull relative to the sails can be designed to make the boat tend to turn upwind when it heels excessively: this reduces the force on the sails, and allows the boat to right itself. This is known as rounding up.
- The boat can be turned upwind to produce the same effect.
- Wind can be spilled from the sails by 'sheeting out', i.e. loosening the sail.
- The sail shape can be altered to reduce its efficiency e.g. tightening the downhaul (see list of nautical terms)
- Lastly, as the boat rolls farther over, wind spills from the top of the sail and the angle of attack lessens the wind's force.
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 capsized when the tip of the mast is in the water.
[edit] Sailing safety
First and foremost:
- Stay on the boat
- Wear a personal floatation device
- Learn to swim
- Learn how to recover someone who has fallen overboard
- respect other seamen and the rules of sailing
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:
- Appropriate floatation aids, including life preservers
- Provision of a safety boat for rescue purposes
- Appropriate first-aid and firefighting equipment
- Carry a knife suitable for cutting rigging or netting in an emergency
- Install jacklines and have the crew wear harnesses connected to them, to secure the crew to the vessel.
- Ensure visibility, use the required running lights and mount at least one radar reflector.
[edit] Man overboard
- For more details on this topic, see Man overboard.
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. A Man overboard situation is likely to be life threatening for any of several related reasons since the most likely cause is rough waters and weather conditions. These degrade the ability to maneuver easily, result in vastly different rates of drift caused by both wind and current to the boat and the unwilling swimmer, and in rough weather the reduced visibility makes fast and sure immediate action to be paramount as it is easy to lose sight of the swimming person. In many waters, including inland Lakes, hypothermia can be a major threat to life, so quick recovery of unwilling swimmers can be life-saving. This requires practice and situational awareness.
The guiding principle is to stop the boat or slow it, if stopping is impossible and immediately marking the location by tossing a PFD or Man Overboard Pole into the water. This is naturally achieved on a sailing boat if the helmsman releases the tiller and dumps the mainsheet so slowing dramatically.
A better approach is to heave-to. Again this will occur naturally if the helmsman pushes the tiller to leeward immediately and ignores the jib-sheets. He also dumps the mainsheet at the same time. (Spinnaker guy also dumped if applicable). The sailing boat will tend to come up to weather and the jib will back. When this backing happens, the tiller must be reversed to point towards the boom. The boat is now hove-to and sensibly close to the MOB. - At this stage the mainsail is loose and flapping and the jib is backed (or spinnaker floging) and the yacht is now nearly stopped and it is just scant seconds since the loss overboard. (A wheel steered boat would move the wheel to bring the yacht towards the wind and when the jib backs he reverses the wheel rotation promptly, while also dumping the mainsheet.)
This should be an instinctive reaction of all helmsmen. It works on all points of sailing. At that stage the helmsman can accomplish the launching of LifeSling, unless another crew member has previously done so. With a bit of luck the yacht will be within the range of the cordage on the recovery apparatus.
[edit] Rules of the road
The Rules of the Road as applied to yachts racing is covered by the Racing Rules of Sailing, governing the interaction of racing yachts with each other. Yachts otherwise under sail, while not racing are obliged to follow the Collision Regulations International Regulations for Preventing Collisions at Sea. Yachts racing after sunset are required to follow the International Rules and not the racing rules.
These regulations are extensive, covering many situations in detail, but the essential principles are:
- Port tack gives way to Starboard tack (when the paths of two boats on opposite tacks cross, the boat with its port side to windward must give way)
- Windward gives way to the leeward, or downwind boat (if on the same tack)
- Overtaking boat shall keep clear.
- Non-Commercial Powerboats usually give way to sailboats
- It is everybody's responsibility to 'avoid a collision', and avoiding action must be taken if these rules are not complied with by another vessel.
[edit] Sailing hulls and hull shapes
Sailing boats can have one, two, or three hulls. Boats with one hull are known as monohulls, while those with two or more are known as multihulls. Multihulls can be further subdivided into catamarans (two hulls), and trimarans (three hulls). A sailing boat is turned by a rudder, which itself is controlled by a tiller or a wheel, while at the same time adjusting the sheeting angle of the sails. 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 ⅓ of the weight of a monohull sailboat. In the case of a standard catamaran there are two similarly sized and shaped slender 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 amas 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 lesser draft reduces the amount of drag, caused by friction and inertia, when moving through the water.
[edit] 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 a single mast and a headsail (generally a jib) in addition to the mainsail. 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. Additionally, Bermuda sloops only have a single sail behind the mast. Other types of sloops are gaff-rigged sloops and lateen sloops. 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 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 barques, barquentines, and full-rigged ships.
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.
[edit] 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).
[edit] 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. If a rope is made of wire, it maintains its rope name as in 'wire rope' halyard.
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.
[edit] 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'. 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, barnacles on the ship's hull would lacerate the sailor.
[edit] Knots
Knots are among the most important things a sailor needs to know. Although only a few are required, the bowline in particular is essential. By also learning the clove hitch and "round turn and two half hitches," one can easily cope with all of the knot requirements of a boat. A more complete grasp of knot-tying includes mastery of the:
- bowline
- clove hitch
- round turn and two half hitches
- rolling hitch
- figure of eight
- reef knot
- sheet bend
- stopper knots
Additional knots are available List of knots
Even the most experienced sailors may forget their knots if they are not performed on a regular basis. For this reason, many sailors constantly practice. Forgetting how to tie an important knot can damage a boat or cause injury.
- http://www.tollesburysc.co.uk/Knots/Knots_gallery.htm (Here are some of the most important knots for beginners to learn)
[edit] Sailing regulations
There are three very basic rules for avoiding a collision at sea:
- Port gives way to starboard.
- The more maneuverable vessel gives way to the less maneuverable vessel. It is generally assumed that this means that power gives way to sail, but this is not normally the case. It is always prudent for a small sailing vessel to stay out of the way of large ships by making an early and obvious turn out of the way.
- If a collision is imminent both vessels must take immediate avoiding action even if they have the right of way according to normal rules. This means that if you have the right of way and a collision appears imminent that you must take avoiding action. Not to do so, if you have the opportunity, may make you the guilty party at an inquiry.
This first point means that boats that are on a possible collision course with boats approaching on their starboard bow give way. On sailing boats this extended to boats that 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 (boat away from the wind). If these rules are purposely not followed, a protest may be called by one of the skippers. The protest will be listened to by an arbitrator on land after the racing day much like a court house hearing, where one will diagram the situation and the other's fault, and the other will have input. Either a form/flyer will be given to diagram the situation, or more commonly with younger sailors, two wooden replicas of boats will be used. The arbitrator will decide who wins the protest.
However there are many other rules besides these, and sailors are expected to know the essentials of boating safety which include;
- The "rules of the road" or International Regulations for Preventing Collisions at Sea (COLREGS) set forth by the International Maritime Organization are particularly relevant to sailors because of their limited maneuverability compared to powered vessels.
- The IALA International Association of Lighthouse Authorities standards for lateral marks, lights, signals, and buoyage and various rules designed to support safe navigation.
- The SOLAS (Safety of Life at Sea) regulations place the obligations for safety on the owners and operators of any boat. These regulations specify the safety equipment needed and emergency procedures to be used.
- When racing, all sailing vessels are expected to follow the Racing Rules of Sailing promulgated by the International Sailing Federation as well as any prescriptions (additional rules) given by the national governing body. When a boat that is racing encounters one that is not, the racing boat must comply with the International Regulations for Preventing Collisions at Sea with respect to the non-racing boat.
[edit] 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. Additionally many high schools and colleges offer sailboat racing programs through the Inter-Scholastic Sailing Association (in the USA) and the Intercollegiate Sailing Association (in the USA and some parts of Canada). 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.
Most sailboat racing is done in sheltered coastal or inland waters. However, in terms of endurance and risk to life, ocean 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 floe 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 International Sailing Federation (ISAF), and the rules under which competitors race are the Racing Rules of Sailing, which can be found on the ISAF web site.
[edit] Sailing traditions and etiquette
There are many esoteric etiquette rules, traditions, and customs that will demonstrate to others advanced knowledge of boating protocol. Fenders are taken in outside ports, a boat flies the flag of its nation of registry, the flag of a host country is flown from the starboard yardarm and is the highest hoisted flag onboard other than a masthead burgee, flags are taken down at night, boats are referred to as female, a boat is not renamed (as superstition says it is bad luck to do so), bananas are considered bad luck aboard sailing vessels, nothing can be deposited into the head (toilet to landlubbers) that has not been digested at least once, etc.
[edit] More Info
Classes of Keelboats (Worldwide List) | |
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10 Metre | 11 Metre | 12 Metre | 2.4 Metre | 5 Metre | 5.5 Metre | 6 Metre | 8 Metre | Achilles 24 | Aloha | Antrim 27 | Beachcomber (22 ft) | Catalina Yachts | Catalina 30 | Cabot 36 | Colin Archer | Contessa 32 | Didi26 | Downeaster | Dragon | Etchells | Farr 40 | Fife | Flying Fifteen | Flying Tiger 10 M | Freedom | Folkboat | Freedom Yachts | Guppy 13 | H-boat | Hallberg-Rassy | International 806 | International Americas Cup Class | IOD | J/22 | J/24 | J/105 |J-Class | Kendall 32 | Knarr |Laser SB3 | Maxi Yacht | Melges 24 | Melges 32 | Monark 540 | Moore 24 | Open 50 Monohull | Open 60 Monohull | Pearson Triton | Red Witch | Ross 930 | San Juan 24 | Sea Sprite 34 | Shark 24 | Shields | Soling | Sonar | Soverel 33 | Squib | Star | Stella | Sydney 38 | Tartan Ten | Tempest | Top Hat 25 | Triton | Vindö | Westsail 32 | Yngling |
Classes and types of catamarans, trimarans and multihulls (worldwide list) | |
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A-Catamaran | ARC 17 | ARC 21 | ARC 22 | Astus 16.1 | Astus 20.1 | Beachcat | Sprint 15 | Dart 16 | Dart 18 | Dragonfly 800 | Formula 16 | Formula 18 | Hobie | Mystere | Proa | RC 27 | RC 30 | Taipan 4.9 | Tornado | Open Ocean Performance Sixties | Unicorn |
[edit] See also
- Sailboat
- Catboat and Sloop
- Catamaran
- Cruising (maritime)
- Day sailer
- Dinghy sailing
- Dinghy racing
- Ketch
- Land sailing
- List of nautical terms
- Planing (sailing)
- Points of sail
- Sail
- Sail-plan
- Single-handed sailing
- Solar sail
- Trimaran
- Yachting
- Yacht charter
- Yacht racing
- History of ship transport
[edit] References
- ^ Casson, Lionel. 1971. Ships and Seamanship in the Ancient World
- ^ As would be seen by a wind in relation to the boat which also has a velocity. The curved surface of a sail serves to deflect the air. Deflecting the air results in a reaction force on the sail and rigging, which pushes the boat in a direction opposite to the deflection. It is often said that lift is generated by the pressure differential on the sails, but this is not entirely true--the pressure differential deflects the air, but it is the deflection that generates the force. Since the air behind the sailboat has been deflected, it now has less energy and is slower and is often called dirty air. Racing sailors try to avoid sailing in dirty air and attempt to give dirty air to opponents where possible. A common technique is trying to get upwind of an opponent, and make them sail in your dirty air, slowing them down
- ^ 360 - 2x35 = 290degrees
- ^ Large sails of big area, spinnakers serve to increase the sail area for more drag downwind
- ^ Forward of means making a smaller angle relative to the bow than the angle that the true wind makes relative to the bow
- ^ Each leg at 45 degrees to the true wind is 0.71miles, but in reality is longer as tacking angles greater than 45 degrees are the norm and leeway is significant also,
- ^ reciprocal. Dictionary.com. Dictionary.com Unabridged (v 1.0.1), Based on the Random House Unabridged Dictionary, © Random House, Inc. 2006. [1].
[edit] External links
- Learn to Sail Manual
- Sailing
- Practical advice on boat and gear purchases
- Learning to Sail Articles
- The Physics of Sailing
- How Sails Really Work Arvel Gentry was largely responsible for delineating the modern theory of Sails. Quoted extensively by Marchaj and others this is his website. Includes articles on how sails really work and the implications for design and trim.
- Sailing and the Tech Dinghy -- MIT's dinghy sailing instruction booklet
- Sailing Simulator from National Geographic
- International Sailing Federation
- Quest for the perfect sail shape
- Online glossary of sailing terms
- Speed sailing records.
- Speed sailing records.
- Another online glossary
- An Introduction to Fractional Sailing
- Sailing news
- Sailing Networks
- Crew Reunited
- Peter Lester NZ sailing commentator
- Sail Power Calculation Web Page
- Free Sailing Book By George D. O’Day
- Roboat - A Fully Autonomous Sailboat