Windsurfing Boards Sails Competitions Olympic Windsurfing Class

Windsurfing (also called boardsailing) is a sport involving travel over water on a small 2-4.7 meter board powered by wind acting on a single sail, that is connected to the board via a flexible joint. The sport is a hybrid between sailing and surfing. The sail board might be considered the most minimalistic version of the modern sailboat, with the major exception that steering is accomplished by tilting the mast and sail rather than with a rudder.

Windsurfers can travel over flat water as long as there is enough wind; they can also cut into breaking waves and perform spectacular stunts. Windsurfing is very versatile by its relation to the sailor. It can mean a peaceful relaxed pastime on the water to some people, it can be a high-stress high-adrenalin sport to others, but it can also be a lifestyle of seeking the endless limits of perfection in skills and self-expression.

Windsurfing is particularly enjoyable at wind strengths of Beaufort 3 or, better, 4 to 5.

1 Boards

Boards used to be classified by length, i.e. shortboards and longboards. In recent years the sport has developed very quickly in materials and techniques. Modern boards are usually less than 3 metres, and are classified according to width and volume. These affect stability and performance.

Beginner boards generally have a daggerboard. Most short boards nowadays are designed to allow for planing, where the board is sliding over the surface of the water, rather than cutting through, and displacing the water. Planing is faster and gives more maneuverability, but requires a different technique from the displacing mode.

Most windsurfers don't even consider sailing if the wind is not enough to plane. All shortboards should be planing with adequate, well tuned sails at wind speeds of 12 knots. The aim of planing at lower winds has driven the development and spread of wider and shorter boards, that plane at wind speeds as low as 8 knots.

The original Windsurfer board invented by Jim Drake and Hoyle Schweitzer had a body made out of polyethylene filled with PVC foam. Later, hollow glass-reinforced epoxy designs were used. Most boards produced today have an expandable polystyrenePolystyrene Density1050 kg/m3 Electrical conductivity(σ)10-16 (m· ohm)-1 Thermal conductivity0. 08 W/(m·K) Polystyrene is a polymer made from styrene, a liquid that is commercially manufactured from petroleum, although it is also found in plants. foam core reinforced with a composite sandwich shell, that can include carbon fiberCarbon fiber is a strong, light and very expensive material. Generally the term "carbon fiber" is used to refer to carbon filament thread, woven carbon thread cloth. The fiber-epoxy composite made with woven carbon cloth is more properly termed carbon fib, kevlarKevlar (also produced by the Teijin Twaron company under the trade name Twaron is a type of high strength synthetic fiber first produced by the DuPont corporation in the early 1960s, following the work of Stephanie Kwolek. It is a registered trademark of, fiberglassThere is a disputed proposal to merge this article with glass-reinforced plastic. See the for discussion. Fiberglass or fibreglass is material made from extremely fine fibers of glass. It is widely used in the manufacture of insulation and textiles. It is, epoxyEpoxy or polyepoxide is an epoxide polymer that cures when mixed with a catalyzing agent or "hardener". The material was developed by I. Farben Industrie of Germany in 1939, and is used for coatings, adhesives and composite materials like glass-reinforced, PVC, veneer, even plywoodPlywood was the first type of engineered wood to be invented. It is made from thin sheets of wood veneer, called plies, which are stacked together with the direction of each ply's grain differing from its neighbors by 90°. The plies are bonded under heat and molded plastic. Racing and wave boards are usually very light (6 to 7 kg), and are made out of carbon sandwich. Such boards are very brittle, and veneer is sometimes used to make them more shock-resistant. Boards aimed at the beginners are heavier (8 to 15 kg) and more robust, contain more fiberglass, or even have an indestructible molded plastic shell.

2 Sails

A modern windsurfing sailA sail is a surface intended to generate thrust by being placed in a wind. Depending on the incident angle of the wind on the surface of the sail, one side of the sail will have a higher air pressure than the other one according to Bernoulli's principle. is made of monofilm (clear PVC film), dacron (woven polyesterSEM picture of a bend in a high surface area polyester fiber with a seven-lobed cross section Polyester is a category of polymers which contain the ester functional group in their main chain. Although polyesters do exist in nature, polyester generally ref) and mylar. Sensitive parts are reinforced with kevlar mesh.

Currently, two designs of a sail are predominant: camber induced and RAF (Rotating Asymmetric Foil). Cambered sails have 1-5 camber inducers, plastic devices at the ends of batten s which cup against the mast. They help to hold a rigid aerofoil shape in the sail, better for speed and stability, but at the cost of manouevrability and generally how light and easy to use the sail feels. The current trend is that only the large race sails have camber inducers. The rigidity of the sail is also determined by a number of batten s.

RAF sails have battens which protrude beyond the back aspect of the mast. They have to flip to the other side of the mast when tacking or jibing, hence the rotation in the name. RAF sails have aerofoil shape on the leeward side only when filled with wind. They can be absolutely flat and depowered when sheeted out. This feature is much appreciated in the freestyle and wave riding disciplines.

In comparison with cambered sails, RAF designs offer less power and stability when sailing straight, but are easier to handle when manoeuvering. Also, RAF sails are much easier to rig.

The leading edge of a sail is called the luff. The mast is in the luff tube. The rear edge is called the leech. The front bottom corner of the sail, where the mast foot protrudes, is called the tack, and the rear corner, to which the boom is attached, is called the clew. The bottom edge, between the clew and the tack, is called the foot.

A windsurfing sail is tensioned at two points: at the tack (by downhaul), and at the clew (by outhaul). There is a set of pulleys for downhauling at the tack and there's a grommet at the clew. Most shape is given to the sail by a very strong downhaul, bending the mast in the luff tube. The outhaul tension is relatively weak, mostly just to keep the sail from flapping.

The sail is tuned by adjusting the downhaul and the outhaul. Generally, the sail has to be trimmed more for stronger winds. More downhaul tension loosens the upper part of the leech, "spilling" the wind at the gusts and shifting the center of effort of the sail down. In contrary, releasing the downhaul tension shifts the center of effort up. More outhaul makes the sail flatter, easier to control, but less powerful, and less outhaul brings more camber, more low-end power, shifts the center of effort to the front, and limits the speed by increasing the aerodynamic resistance.

Different sails are used for various disciplines of windsurfing: wave, freestyle, freeride, race. The main features of wave sails are that they reinforced to survive the surf, and are absolutely flat when depowered to allow riding the waves like the surfers do. Freestyle sails are also flat when depowered, and have high low-end power to allow quick accelerations. Freeride sails are all-rounders that are comfortable to use and are meant for recreational windsurfing. Racing sails, obviously, provide speed at the expense of qualities like comfort or maneuverability.

The size of the sail is measured in square metres and it can be anything from 3m² to 6.5m² for wave sails and from 6m² to 12.5m² for racing sails, with ranges for freestyle and freeride sails spanning somewhere between these extremes. There might be exceptions to these ranges, though, learning sails for children being as small as 1.7m² and world-record speed racing sails being up to 15m² large.

3 Competitions

In windsurfing competitions, there are the following disciplines:

Olympic Windsurfing Class
Formula Windsurfing Class
Slalom
Super X
Speed Racing
Freestyle
Wave

Freestyle and Wave are judged competitions, the sailor with best technique and diversity wins. Olympic Boardsailing, Formula windsurfing, Slalom and SuperX are races where many sailors compete on a course, and Speed Racing is a race where sailors compete on a straight 500 m course in turns.

3.1 Olympic Windsurfing Class

In Olympic Windsurfing 'one design' boards are used. All sailors use the same long boards with daggerboards and the same relatively small sails. This choice of equipment is motivated by the requirement that the board could be used in a wide range of sailing conditions, both planing and non-planing. This is especially important for its use in the Olympic Games, as the event has to take place regardless of whether there is enough wind for planing.

Currently Mistral One Design is the olympic class. It was introduced in the 1996 Summer Olympics. Before that, Lechner design was used in 1992 and 1988, and Windglider design was used for the Olympic boardsailing event in 1984 Summer Olympics. Mistral One Design will be replaced by Neil Pryde RS:X in the 2008 Summer Olympics.

3.2 Formula Windsurfing Class

Formula windsurfing is quite a recent development aiming to revolutionise windsurfing by making the competitions more spectacular and less dependent on high winds. Formula is a class of boards about 1 m wide. They have fins or skegs as long as 70 cm and carry sails up to 12.5 m². Contrary to the olympic class, sailors can choose boards of different models, as long as they are certified as Formula boards, and fit fins and sails of different sizes.

Large sails in combination with the 'wide-style' design allow planing in very low wind conditions. However, if these requirements are not met, the boards cannot be used and events will not take place, as non-planing sailing is very difficult with this design. Formula boards are only used on flat water.

Formula boards have excellent upwind and downwind ability, but are not very comfortable on a beam reach . This explains why the course is usually a box with longer upwind and downwind legs, or just a simple upwind-downwind loop.

3.3 Slalom

Slalom is a fast funboard race in a course shaped like a figure of eight. Most of the course goes on a beam reach with floating marks that have to be jibed around. Slalom boards are small and narrow, and require high winds. Funboard class racing rules require the wind of 9-35 knots for the slalom event to take place.

3.4 Super X

This is a relatively new discipline in windsurfing competitions. It is a cross between freestyle and slalom. The competing sailors are racing on a short downwind slalom course, have to use duck jibe s on all turns, and are required to perform several tricks along the way, such as jump over an obstacle, body drag or even front loop . The sailors are required to wear protective equipment in these competitions.

3.5 Speed Racing

Speed racing competitions take place on a straight 500 m course. The sailors have additional 300 m to accelerate before their time is measured on the speed course. The sailors race in turns, and their time of course completion is measured.

3.6 Freestyle

Freestyle is a timed event which is judged. The surfer who has the greatest repertoire, or manages to complete most stunts, wins.

3.7 Wave

Similar to freestyle (though wavesailing preceded freestyle) except that the stunts are generally performed in surf.

4 Records

World speed sailing record : 46.82kts (54 mp/h or 24 m/s) by Finian Maynard (irish) on the 13th November 2004 at Les Saintes Maries de la mer (France).

5 External links

Water sports Boardsports Sailing

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