Ski - AbsoluteAstronomy.com

A ski is a long, flat device worn on the foot, usually attached through a boot, designed to help the wearer slide smoothly over snow

Snow

Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...

. Originally intended as an aid to travel

Travel

Travel is the movement of people or objects between relatively distant geographical locations. 'Travel' can also include relatively short stays between successive movements.-Etymology:...

in snowy regions, they are now mainly used for recreational and sporting purposes. Also, a ski may denote a similar device used for other purposes than skiing

Skiing

Skiing is a recreational activity using skis as equipment for traveling over snow. Skis are used in conjunction with boots that connect to the ski with use of a binding....

, for example, for steering snowmobile

Snowmobile

A snowmobile, also known in some places as a snowmachine, or sled,is a land vehicle for winter travel on snow. Designed to be operated on snow and ice, they require no road or trail. Design variations enable some machines to operate in deep snow or forests; most are used on open terrain, including...

History

The Nordic

Nordic countries

The Nordic countries make up a region in Northern Europe and the North Atlantic which consists of Denmark, Finland, Iceland, Norway and Sweden and their associated territories, the Faroe Islands, Greenland and Åland...

ski technology was adapted during the early twentieth century to enable skiers to turn at higher speeds. New ski and binding

Ski binding

A ski binding is an attachment which anchors a ski boot to the ski. There are different types of bindings for different types of skiing.-Universal designs:...

designs, coupled with the introduction of ski lift

Ski lift

The term ski lift generally refers to any transport device that carries skiers up a hill. A ski lift may fall into one of the following three main classes:-Lift systems and networks:...

s and snowcat

Snowcat

A snowcat is an enclosed-cab, truck sized, fully tracked vehicle designed to move on snow. Snowcats are often referred to as 'trail groomers' because of their use for grooming ski trails or snowmobile trails...

s to carry skiers up mountains, enabled the development of alpine skis. Meanwhile advances in technology in the Nordic camp allowed for the development of special skis for skating and ski jumping.

Construction

Skis were originally wooden planks made from a single piece of wood. They are now usually made from a complex assembly of components including glass fibre

Glass-reinforced plastic

Fiberglass , is a fiber reinforced polymer made of a plastic matrix reinforced by fine fibers of glass. It is also known as GFK ....

, Kevlar

Kevlar

Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

, aluminum, other polymer

Polymer

A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

s, and composite material

Composite material

Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or...

s such as carbon fiber

Carbon fiber

Carbon fiber, alternatively graphite fiber, carbon graphite or CF, is a material consisting of fibers about 5–10 μm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in crystals that are more or less aligned parallel to the long axis of the fiber...

, though many contain wood cores. Nearly all modern skis use a running base of high-molecular-weight polyethylene, and alpine skis use carbon-steel edges. These components are put together through a variety of ski manufacturing techniques

Ski manufacturing techniques

Ski manufacturing techniques include: Laminated construction, torsion-box construction, and single-shell construction. Laminated skis are constructed by layering and compressing various materials together, such as steel and plastic. Torsion-box manufacturing involves wrapping a soft inner core with...

.

Most skis are long and thin and curve upwards at the front to prevent digging into the snow. The skier is attached by binding

Ski binding

A ski binding is an attachment which anchors a ski boot to the ski. There are different types of bindings for different types of skiing.-Universal designs:...

s which latch ski boots to the skis. Beginning in the early 2000s, many ski manufacturers began designing skis and bindings

Ski binding

A ski binding is an attachment which anchors a ski boot to the ski. There are different types of bindings for different types of skiing.-Universal designs:...

together, creating an integrated binding system. These systems serve three purposes. Firstly, they often use a railroad track design, to allow the toe and heel pieces to slide, which in turn allows the ski to flex deeply, without a non-flexing spot underfoot due to the binding .Secondly, it gives the skier a better control on his skis, since the binding is not only screwed on the ski, but integrated in the ski core via inserts. Thirdly, it requires the consumer to purchase both skis and bindings from the same manufacturer due to the proprietary nature of the system, thus increasing sales.

Types

Many types of skis exist, designed for different needs, of which the following are a selection.

Alpine

Like all skis, the original alpine "downhill" skis were little more than wood planks. Early alpine skis, developed in Switzerland and Austria during the 1890s, were wider, shorter versions of the standard Huitfeldt Telemark model, meant to be more agile in steep terrain and in deeper snow. Rudolf Lettner of Salzburg began marketing steel edges in 1928, enabling the ski to grip on hard snow ice. The following year Guido Reuge introduced the Kandahar binding, providing for heel lock-down and improved control for downhill skiing. Downhill ski construction has evolved into much more sophisticated technologies. The use of composite materials, such as carbon-Kevlar

Kevlar

, made skis stronger, lighter, and more durable.

By the late 1980s World Cup giant slalom skiers were getting race-stock skis with deeper sidecuts. In 1991, designers at Elan

Elan (company)

Elan is a Slovenian company, located in Begunje, specializing in the production of sporting goods. It is best known for its skis and snowboards. Other products include sailboats from 30 to 50 ft length, motor yachts, apparel , equipment for sports facilities...

produced a very exaggerated version of this race ski, and in 1993 introduced a recreational version described by the company as offering a "parabolic" turn shape. This became the prototype of modern "shaped" skis

Sidecut

The sidecut is a general term for the inner curvature of a ski, snowboard, or skiboard. The sidecut depth is measured as the distance between the waist of the board and an imaginary straight line that strikes both of the contact points at the tip and tail. The sidecut radius is the radial...

(when viewed from above or below, the centre or "waist" is significantly narrower than the tip and tail). Virtually all modern skis are made with some degree of side cut. The more dramatic the difference between the widths of the tip, waist and tail, coupled with the length, stiffness and camber of the ski, the shorter the "natural" turning radius.

Skis used in downhill race events are longer, with a subtle side cut, built for speed and wide turns. Slalom skis—as well as many recreational skis—are shorter with a greater side cut to facilitate tighter, easier turns. Many ski manufacturers label their skis with the turning radius on the top. For a racing slalom ski, this can be as low as 12 metres and for Super-G they are normally at 33 metres. For off-piste

Piste

A piste is a marked ski run or path down a mountain for snow skiing, snowboarding, or other mountain sports. The term is European, from the French for trail or track, synonymous with trail, slope, or groomed run in North America....

skis the trend is towards wider skis that better float on top of powder snow.

The ski is turned by applying pressure, rotation and edge angle. When the ski is set at an angle the edge cuts into the snow, the ski will follow the arc and hence turn the skier; a practice known as carving a turn. While old fashioned "straight skis" which had little side cut could carve turn

Carve turn

A carve turn is a skiing term, used to refer to a turning technique in which the ski shifts to one side or the other on its edges. In this case, the ski turns itself and is driven by the sidecut geometry while losing no speed, unlike a normal parallel turn....

s, great leg strength was required to generate the enormous pressure necessary to flex them into a curved shape, a shape called reverse camber. When a modern ski is tilted on to its edge, a gap is created between the ground and the middle of the ski (under the binding) as only the sides near the tip and the tail touch the snow. Then, as the skier gently applies pressure, the ski bends easily into reverse camber.

Influenced by snowboarding

Snowboarding

Snowboarding is a sport that involves descending a slope that is covered with snow on a snowboard attached to a rider's feet using a special boot set onto mounted binding. The development of snowboarding was inspired by skateboarding, sledding, surfing and skiing. It was developed in the U.S.A...

, during the 1990s the side cut

Sidecut

became significantly more pronounced to make it easier for skiers to carve turns. Such skis were once termed carving skis, shaped skis, or parabolic skis to differentiate them from the more traditional straighter skis, but nearly all modern recreational skis are produced with a large degree of side cut.

Reverse Camber

Reverse Camber is a term that describes skis with something other than the traditional camber shape. Reverse camber skis have tips and tails that curve up while the length between them is flat. This allows the ski tip to remain above soft powder snow. The first production ski to feature reverse camber was the Volant Spatula

Volant Spatula

The Spatula was a ski manufactured by Volant skis from 2001 to 2003. It was the first production ski to feature reverse camber as well as reverse side cut. The ski was initially envisioned by professional freeskier Shane McConkey as early as 1996, and he convinced the company to manufacture the...

which premiered in the 2002–2003 season. Since then, many manufacturers have experimented with the concept and today rocker and reverse camber can be found in dozens of ski models.

Twin-tip

Twin-tip ski

A modified version of their alpine counterparts, twin-tip skis are designed to enable a skier to take off and land backward while jumping and to ski backwards down a slope. The name "twin-tip" comes from the shape of the ski...

s are skis with turned-up ends at both the front and rear. They make it easier to ski backwards, allowing reversed take-offs and landings when performing aerial maneuvers. The turned-up tail allows less application of aft pressure on the ski, causing it to release from a turn earlier than a non-twin-tip ski. Twin-tip skis are generally wider at the tip, tail, and underfoot and constructed of softer materials to cushion landings. Bindings are typically mounted closer to the centre of the ski to facilitate the balance of fore and aft pressure while skiing backwards or "switch", and built lower to the ski for easy rail sliding. Some skis are also manufactured with special materials or a different side cut design under and close to the foot to facilitate rail sliding.

In the past five years twin tips have become popular among youth skiers, ages 14–21. The popularity explosion of twin-tip skis created a push for the inclusion of more terrain park elements at ski areas. Once considered a passing fad, twin-tip skis have become a staple in the product line of all major ski-producing companies worldwide, with a few specializing in twin tips. Line Skis, started by Jason Levinthal, was the first company to market only twin-tip skis. The first twin-tip ski was the Olin Mark IV Comp introduced in 1974. The first company to successfully market a twin-tip ski was Salomon, with their Teneighty ski. While the first person to first introduce the Twin-tip to Salomon was famous Freeskier "Michael Douglas". These skis are used by freestylers also known as freeskiers.

Alpine touring ski

The Alpine touring ski

Ski touring

Ski touring is a form of backcountry skiing involving traveling over the winter landscape on skis under human power rather than through the assistance of ski lifts or snow vehicles. It can take place in terrain ranging from perfectly flat to extremely steep...

is a modified lightweight downhill ski with an alpine touring binding. Like the backcountry ski, it is designed for unbroken snow. For climbing steep slopes, skins (originally made of seal fur, but now made of synthetic materials) can be attached at the base of the ski. The heel of the ski boot can be clamped to the ski when skiing downhill and released when climbing. The type of ski is mainly used with alpine touring boots, which are rigid but lighter than downhill skiing boots, but may be fixed with a binding suitable for skiing in technical mountaineering boots.

Monoski

The monoski

Monoski

The term monoski may refer to either of two unrelated pieces of ski equipment. It is the device used in the sport of monoskiing.The monoski, invented in the 1960s and popularized in the 1970s and '80s by monoskiers like Mike Doyle, is similar to a snowboard in that both feet are attached to one...

is wide enough to attach both boots to a single ski. After a brief boom in the 1980s, only a few thousand enthusiasts continue to use it. Due to its extra width and flotation in deep snow, enthusiasts claim it to be a superior powder ski. The monoski is produced by a half dozen companies worldwide in limited quantities.

Telemark

The Telemark ski

Telemark skiing

Telemark skiing is a form of skiing using the Telemark turn. Unlike alpine skiing equipment, the skis used for telemarking either have a binding that only connects the boot to the ski at the toes, just as in cross-country skiing, or may be released to only connect there.Telemark turns are led with...

is a downhill or touring

Ski touring

ski, where the binding attaches only at the toe. The Telemark ski was the first ski with a significant side cut, and evolved in the Telemark region of southern Norway early in the 19th century. It was popularized by Sondre Norheim

Sondre Norheim

Sondre Norheim, born Sondre Auverson, was a Norwegian skier and pioneer of modern skiing. Sondre Norheim is known as the father of Telemark skiing.-Background:...

of Morgedal in Telemark, when he demonstrated the ski and the Telemark style of skiing to the public at Christiana, Norway beginning in 1868. The fact that the foot is only attached to the ski at the toes means that flexible ski boots are worn. The primary turning technique involves pushing one foot forward and lifting the heel of the other foot.

Cross-country

Cross-country ski

Cross-country skiing

Cross-country skiing is a winter sport in which participants propel themselves across snow-covered terrain using skis and poles...

s are very light and narrow, and usually have slight sidecut

Sidecut

, though some newer skis are a sidecut more like an alpine ski. The boots attach to the bindings at the toes only. Three binding systems are popular: Rottefella's NNN, Salomon's SNS profil, and SNS pilot.

The ski bases are waxed to reduce friction during forward motion, and kick wax can also be applied for adhesion when walking uphill. Some waxless models may have patterns on the bottom to increase the friction when the ski slides backward.

The two major techniques are classical (traditional striding) and freestyle or skating, which was developed in the 1980s. Skating skis are shorter than classical skis and do not need grip wax. The skating technique is used in biathlon

Biathlon

Biathlon is a term used to describe any sporting event made up of two disciplines. However, biathlon usually refers specifically to the winter sport that combines cross-country skiing and rifle shooting...

s. V1 skating is done when going up a hill and one arm is the lead arm which poles ahead of the second with its side. V2 skating is done while going down a hill or on a flat area. It involves poling with every stride of the ski.

Backcountry

Skis for mountain/backcountry/cross-country free range skiing

Backcountry skiing

Backcountry skiing is skiing in a sparsely inhabited rural region over ungroomed and unmarked slopes or pistes, including skiing in unmarked or unpatrolled areas either within the ski resort's boundaries or in the backcountry, frequently amongst trees , usually in pursuit of fresh fallen powder...

are designed for skiing on unbroken snow where an established track is lacking. These skis are characteristically 10 cm or more in width and often fitted with cable binding

Ski binding

A ski binding is an attachment which anchors a ski boot to the ski. There are different types of bindings for different types of skiing.-Universal designs:...

s to provide general sturdiness, and to make it easier to extract one's feet from deep snow banks, in case it should be impossible to reach the bindings by hand. This is also the model used by military forces trained to fight in winter conditions, and the most closely related to the original ski. The widest backcountry skis are often called Big Mountain skis.

Mogul

These skis are specifically designed for moguls. They typically have a different flex pattern, are narrower and have a smaller sidecut than a common carving ski. The differences in the flex pattern of the ski are made to let the ski absorb the impact of the moguls with the tip, and to have a tail stiff enough to push on the last mogul, while not being as stiff as it won't bend on it.

Custom-built skis

Most skis are mass-produced in large factories, with runs of 50,000 pairs of a specific model and size to achieve economies of scale. Since 2004 a few small companies have emerged in the United States dedicated to crafting custom-made skis, one pair at a time, each pair custom-designed for a specific customer. Best know of these shops are Wagner Custom (Telluride, Colorado), Igneous (Jackson, Wyoming) and Folsom (Boulder, Colorado). The custom-design process typically begins with a detailed questionnaire and interview, which the designer uses to determine the skier's needs. The designer can change flex, materials and ski shape to suit the skier's skills, weight and target snow and terrain. Core materials, structural components, base and edge materials can be of superior quality and durability. Customers often design their own topsheets.

Use on vehicles

Skis are sometimes used in place of tires on vehicle

Vehicle

A vehicle is a device that is designed or used to transport people or cargo. Most often vehicles are manufactured, such as bicycles, cars, motorcycles, trains, ships, boats, and aircraft....

s intended to travel over snow. The best known example of this is the snowmobile

Snowmobile

, but larger vehicles such as aerosan

Aerosan

An aerosani is a type of propeller-driven snowmobile, running on skis, used for communications, mail deliveries, medical aid, emergency recovery and border patrolling in northern Russia, as well as for recreation...

s, snow coach

Snow coach

A snow coach is a specialized passenger transport vehicle, designed to operate over snow or ice, similar to alarge, multi-passenger snowcat that is equipped with bus style seating. These vehicles may have multiple sets of very large low pressure tires or they may have tracks...

es, and snow planes also employ skis.

Ski in modern art

As the water and mechanical sports, ski also was a subject of inspiration for the artists of the twentieth century.

External links

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

History

Construction

Types

Alpine

Reverse Camber

Twin-tip

Alpine touring ski

Monoski

Telemark

Cross-country

Backcountry

Mogul

Custom-built skis

Use on vehicles

Ski in modern art

See also

External links