A kayak (sometimes generalised as a canoe) is a small human-powered boat that traditionally has a covered deck, and one or more cockpits, each seating one paddler who strokes a double-bladed paddle. The cockpit is covered by a spraydeck (skirt) that keeps the inside of the boat (and the paddler's lower body) dry. The spraydeck or similar waterproof covering attaches securely to the edges of the cockpit, preventing the entry of water from waves or spray, and making it possible, in some boats, to roll the kayak, capsizing and righting the boat without it filling with water or ejecting the passenger. Some modern kayaks have modified the traditional design in a variety of way, such as eliminating cockpits, seating the paddler(s) on top of the boat, having inflated air chambers surrounding the boat, and replacing paddles with other propulsion methods.
Kayaks are generally differentiated from canoes by the sitting position of the paddler and the number of blades on the paddle. In a kayak the paddler faces forward, legs in front, using a double bladed paddle. In a canoe the paddler faces forward and sits or kneels in the boat, using a single bladed paddle. In some parts of the world, such as the United Kingdom, kayaks are considered a subtype of canoes. Continental European and British canoeing clubs and associations of the 19th Century used craft similar to kayaks, but referred to them as canoes. This explains the naming of the International and National Governing bodies of the sport of Canoeing.
The kayak was invented and first used by the native Ainu, Aleut and Eskimo hunters in sub-Arctic regions of northeastern Asia, North America and Greenland. Inuit/Eskimo Kayaks are a type of a generic class of boat of Canoe Shape.
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Kayaks (Inuktitut: qajaq, Inuktitut syllabics: ᖃᔭᖅ) were originally developed by indigenous Arctic people, who used the boats to hunt on inland lakes, rivers and coastal waters of the Arctic Ocean, North Atlantic, Bering Sea and North Pacific oceans. These first kayaks were constructed from stitched seal or other animal skins stretched over a wooden frame (made from driftwood, since many of their habitats were treeless). Kayaks are at least 4,000 years old.[1] The oldest existing kayaks are exhibited in the North America department of the State Museum of Ethnology in Munich.[2]
Native people made many types of boat for different purposes. The baidarka, developed by indigenous cultures in Alaska, was also made in double or triple cockpit designs, for hunting and transporting passengers or goods. An umiak is a large open sea canoe, ranging from 17 to 30 feet (5.2 to 9.1 m), made with seal skins and wood. It was originally paddled with single-bladed paddles and typically had more than one paddler.
Native builders designed and built their boats employing their experience in combination with knowledge orally–transmitted traditions. The word "kayak" means "man's boat" or "hunter's boat", and native kayaks were a personal craft, each built by the man who used it (with assistance from his wife, who sewed the skins) closely fitting his size for maximum maneuverability. A special skin jacket, Tuilik, was then laced to the kayak, creating a waterproof seal. This enabled the eskimo roll to become the preferred method of regaining posture after turning upside down (kayakers consider "capsize" to refer to separation of paddler and vessel) especially as few Eskimos could swim; their waters are too cold for a swimmer to survive for long.[3]
The modern version of a tuilik is a spraydeck made of waterproof synthetic material stretchy enough to fit tightly around the cockpit rim and body of the kayaker, which can be released rapidly from the cockpit to permit easy exit.
The builder used found materials to create a kayak measured to his own body. For example: the length was typically three times the span of his outstretched arms. The width at the cockpit was the width of the builder's hips plus two fists (and sometimes less). The typical depth was his fist plus the outstretched thumb (hitch hiker). Thus typical dimensions were about 17 feet (5.2 m) long by 20–22 inches (51–56 cm) wide by 7 inches (18 cm) deep. This measurement system confounded early European explorers who tried to duplicate the kayak because each kayak was a little different.
Traditional kayaks encompass three types of boat: Baidarkas, from the Alaskan & Aleutian seas, the oldest design, whose rounded shape and numerous chines give them an almost Blimp-like appearance; West Greenland kayaks, with fewer chines and a more angular shape, with gunwales rising to a point at the bow and stern; and East Greenland kayaks that appear similar to the West Greenland style, but often fit more snugly to the paddler and possess a steeper angle between gunwale and stem which lend maneuverability.
Most of the Eskimo peoples from the Aleutian Islands eastward to Greenland relied on the kayak for hunting a variety of prey — primarily seals, though whales and caribou were important in some areas. Skin on frame kayaks are still being used for hunting by Inuit people in Greenland. In other parts of the world homebuilders are continuing the tradition of skin on frame kayaks albeit with modern skins of canvas or synthetic fabric.
Contemporary kayaks trace their origins primarily to the native boats of Alaska, northern Canada, and Southwest Greenland. Wooden kayaks and fabric kayaks on wooden frames (such as the Klepper) dominated the market up until the 1950s, when fiberglass boats were first introduced in the US, and inflatable rubberized fabric boats were first introduced in Europe. Rotomolded plastic kayaks first appeared in 1973. The development of plastic and rubberized inflatable kayaks arguably initiated the development of freestyle kayaking as we see it today, since these boats could be made smaller, stronger and more resilient than fiberglass boats.
Kayak design is largely a matter of trade-offs: directional stability ("tracking") vs maneuverability; stability vs speed; and primary vs secondary stability.
As a general rule, a longer kayak is faster, but the higher potential speed is largely offset by increased friction. Kayaks that are built to cover longer distances such as touring and sea kayaks are longer, generally 16 to 19 feet (4.9 to 5.8 m). Whitewater kayaks, which generally depend upon river current for their forward motion, are short, to maximize maneuverability. These kayaks rarely exceed 8 feet (2.4 m) in length, and playboats may be only 5–6 feet (1.5–1.8 m) long. Recreational kayak designers compromise between tracking and maneuverability, ranging from 9–14 feet (2.7–4.3 m).
Primary (sometimes called initial) stability describes how much a boat tips, or rocks back and forth when displaced from level by water movement or paddler weight shifts. Secondary (final) stability describes how readily a boat capsizes. Primary stability is often a big concern to a beginner, while secondary stability matters more to experienced travelers who may frequent rougher waters. Primary stability increases as the boat's volume moves away from the centerline. For example, catamarans offer high primary stability and little secondary stability, given that their volume is on either edge of the boat.
The shape of the hull's cross–section affects both manueverability and stability. Hull shapes are categorized by roundness/flatness, whether it has a "V" shape at various points, and by the presence and severity of a chine, where the side and bottom of a hull meet at an angle, creating an edge below the gunwales. This cross–section may vary along the length of the boat. Kayaks with only moderate primary, but excellent secondary stability are, in general, considered more seaworthy, especially in challenging conditions.
A V-shaped hull tends to ease traveling straight (track), but makes turning harder. V-shaped hulls also have the greatest secondary stability.
Conversely, flat-bottomed hulls are easy to turn, but harder to direct in a constant direction. They have the greatest primary stability, and the least secondary stability.
The chine typically increases secondary stability by effectively widening the beam of the boat when it heels (tips). Sea kayaks, designed for open water and rough conditions, are generally narrower 22–25 inches (56–63 cm) and have more secondary stability than recreational kayaks, which are wider 26–30 inches (66–76 cm) have a flatter hull shape, and more primary stability.
Kayak hulls are categorized according to the shape from bow to stern
Common shapes include:
Length alone does not fully predict a kayak's maneuverability: a second design element is rocker, its lengthwise curvature. A heavily rockered boat curves more, shortening its effective waterline. For example, an 18-foot (5.5 m) kayak with no rocker is in the water from end to end. In contrast, the bow and stern of a rockered boat are out of the water, shortening its lengthwise waterline to only 16 ft (4.9 m). Rocker is generally most evident at the ends, and in moderation improves handling. Similarly, although a rockered whitewater boat may only be a few feet shorter than a typical recreational kayak, its waterline is far shorter and its maneuverability far greater. When surfing a heavily rockered boat is less likely to lock into the wave as the bow and stern are still above water. A boat with less rocker will cut into the wave and make it harder to turn while surfing.
Modern kayaks differ greatly from native kayaks in every aspect—from initial conception through design, manufacturing and usage. Modern kayaks are designed with CAD (Computer Aided Design) software, often in combination with CAD customized for naval design; in some cases a free stitch and glue package is available for kayak design.[4]
Modern kayaks serve diverse purposes, ranging from slow and easy touring on placid water, to racing and complex maneuvering in fast-moving whitewater, to fishing and long-distance ocean excursions. Modern materials and construction techniques make it possible to effectively serve these needs while continuing to leverage the insights of the original Arctic inventors.
Kayaks are long—19 feet (5.8 m), short—6 feet (1.8 m), wide—36 inches (91 cm), or as narrow as the paddler's hips. They may attach one or two stabilizing hulls (outriggers) , have twin hulls like catamarans, inflate or fold. They move via paddles, pedals that turn propellers or underwater flippers, under sail, or motor. They're made of wood/canvas, wood, carbon fiber, fiberglass, Kevlar, polyethylene, polyester, rubberized fabric, neoprene, Nitrylon, polyvinyl chloride, polyurethane, Carbon Fibre and aluminum. They may sport rudders, fins, bulkheads, seats, eyelets, foot braces and cargo hatches. They accommodate 1-3 or more paddlers/riders.
Fiberglass hulls are stiffer, lighter, and less readily scratched than plastic hulls, though they are more prone to damage from impact. Most modern kayaks have steep V sections at the bow and stern, and a shallow V amidships.
Major Kayak Types |
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Sea Kayak |
Whitewater kayak |
Recreational kayak |
Surf skis |
Racing kayak |
Modern kayaks have evolved into specialized types that may be broadly categorized according to their application as sea or touring kayaks, whitewater (or river) kayaks, surf kayaks, and racing kayaks, and hybrids, broadly labeled recreational kayaks. The label "kayak" is often misapplied to other small, human-powered vessels not descended from the kayak tradition, including multi-hull or outrigger boats and those which elevate above the water on hydrofoils.
Recreational kayaks are designed for the casual paddler interested in fishing, photography, or a peaceful paddle on a lake or flatwater stream. They presently make up the largest segment of kayak sales. Compared to other kayaks, recreational kayaks have a larger cockpit for easier entry and exit and a wider beam (27–36 inches (69–91 cm) for more stability. They are generally less than 12 feet (3.7 m) in length and have limited cargo capacity. Less expensive materials like polyethylene and fewer options keep these boats inexpensive (USD 300–580). Most canoe/kayak clubs offer introductory instruction in recreational boats. They do not perform as well in the sea. The recreational kayak is usually a type of touring kayak.[5]
Sea kayaks are typically designed for travel by one or two paddlers on open water and in many cases trade maneuverability for seaworthiness, stability, and cargo capacity. Sea-kayak sub-types include open-deck "sit-on-top" kayaks, recreational kayaks, and collapsible "skin-on-frame" boats.
The sea kayak, though descended directly from traditional types, is implemented in a variety of materials. Sea kayaks typically have a longer waterline, and provisions for below-deck storage of cargo. Sea kayaks may also have rudders or skegs (fixed rudder) and upturned bow or stern profiles for wave shedding. Modern sea kayaks often have two or more internal bulkheads. Sea kayaks often accommodate two or sometimes three paddlers.
Sealed-hull (unsinkable) craft were developed for leisure use, as derivatives of surfboards (e.g. paddle or wave skis), or for surf conditions. Variants include planing surf craft, touring kayaks, and sea marathon kayaks. Increasingly, manufacturers build leisure 'sit-on-top' variants of extreme sports craft, typically using polyethylene to ensure strength and affordability[6], often with a skeg for directional stability. Water that enters the cockpit drains out through scupper holes—tubes that run from the cockpit to the bottom of the hull.
Sit-on-top kayaks come in 1-4 paddler configurations. Sit-on-top kayaks are particularly popular for fishing and SCUBA diving, since participants need to easily enter and exit the water, change seating positions, and access hatches and storage wells. Ordinarily the seat of a sit-on-top is slightly above water level, so the center of gravity for the paddler is higher than in a traditional kayak. To compensate for the higher center of gravity, sit-on-tops are often wider and slower than a traditional kayak of the same length.
An umbrella term, Skin on Frame boats are more traditional in design, materials, and construction. They are often the lightest kayaks, and were traditionally made of driftwood pegged or lashed together and stretched seal skin, as those were the most readily available materials in the Arctic regions. Today, seal skin is usually replaced with canvas or nylon cloth covered with paint, neoprene, or a hypalon rubber coating and the wood skeleton is replaced with aluminum.
A special type of skin-on-frame kayak is the folding kayak. It is the closest descendant of the original Arctic kayak. A folder is a modern kayak with a collapsible frame, of wood, aluminum or plastic, or a combination thereof, and a skin of water-resistant and durable fabric. Many types have integral air sponsons inside the hull, increasing secondary stability and making the kayaks virtually unsinkable.
Folders are known for durability, stability, and longevity. The Klepper Aerius I, a single–seater, has also been used successfully for whitewater kayaking, due to its durability and excellent maneuverability, often survives frequent use for more than 20 years.
Specialty surf boats typically have flat bottoms, and hard edges, similar to surf boards. The design of a surf kayak promotes the use of an ocean surf wave (moving wave) as opposed to a river or feature wave (moving water). They are typically made from rotomolded plastic, or fiberglass.
Surf kayaking comes in two main varieties, High Performance (HP) and International Class (IC). HP boats tend to have a lot of nose rocker, little to no tail rocker, flat hulls, sharp rails and up to four fins set up as either a three fin thruster or a quad fin. This enables them to move at high speed and maneuver dynamically. IC boats have to be at least 3 meters (10 ft) long and until a recent rule change had to have a convex hull; now flat and slightly concave hulls are also allowed, although fins are not. Surfing on international boats tends to be smoother and more flowing, and they are thought of as kayaking's long boarding. Surf boats come in a variety of materials ranging from tough but heavy plastics to super light, super stiff but fragile foam–cored Kevlar. Surf kayaking has become popular in traditional surfing locations, as well as new locations such as the Great Lakes.
Surf skis, are specialized narrow and long boats for racing, surfing breaking waves and surf-zone rescues.
A variation on the closed cockpit surf kayak is called a waveski. Although the waveski offers dynamics similar to a sit–on–top, its paddling technique and surfing performance and construction can be similar to surfboard designs.
Plastic whitewater kayaks are rotomolded in a semi-rigid, high impact plastic, usually polyethylene. Careful construction ensures that the boat remains structurally sound when subjected to fast-moving water. The plastic hull allows these kayaks to bounce off rocks without leaking, although they scratch and eventually wear through with enough use. Whitewater kayaks range from 4 to 10 feet (1.2 to 3.0 m) long. There are two main types of whitewater kayak: most experienced paddlers own one of each.
One type, the playboat, is short, with a scooped bow and blunt stern. These trade speed and stability for high maneuverability. Their primary use is performing tricks in individual water features or short stretches of river. In playboating or freestyle competition (also known as rodeo boating), kayakers exploit the complex currents of rapids to execute a series of tricks, which are scored for skill and style.
The other primary type is the creek boat, which gets its name from its purpose: running narrow, low-volume waterways. Creekboats are longer and have far more volume than playboats, which makes them more stable, faster and higher-floating. Many paddlers use creekboats in "short boat" downriver races, and they are often seen on large rivers where their extra stability and speed may be necessary to get through rapids.
Between the creekboat and playboat extremes is a category called river–running kayaks. These medium–sized boats are designed for rivers of moderate to high volume, and some, known as river running playboats, are capable of basic playboating moves. They are typically owned by paddlers who do not have enough whitewater involvement to warrant the purchase of more–specialized boats.
Squirt Boating involves paddling both on the surface of the river and underwater. Squirt boats must be custom-fitted to the paddler to ensure comfort while maintaining the low interior volume necessary to allow the paddler to submerge completely in the river.
Polyethylene has replaced fiberglass as a construction material for most types of kayaks. However, squirt boat and racing kayaks still perform better in the fiberglass versions.
White water racers combine a fast, unstable lower hull portion with a flared upper hull portion to combine flat water racing speed with extra stability in open water: they are not fitted with rudders and have similar manoeuvrability to flat water racers. They usually require substantial skill to achieve stability, due to extremely narrow hulls.
Whitewater racing kayaks, like all racing kayaks, are made to regulation lengths, usually of fibre reinforced resin (usually epoxy or polyester reinforced with kevlar, glass fibre, carbon fibre, or some combination). This form of construction is stiffer and has a harder skin than non-reinforced plastic construction such as rotomoulded polyethylene: stiffer means faster, and harder means fewer scratches and therefore also faster.
The three types of Canoe sprint kayaks (sometimes termed 'sprint boats') are K-1 (single paddler), K-2 (two paddlers) and K-4 (four paddlers). A flatwater racing K1's maximum length governed by the ICF is 17 feet (5.2 m). These boats are raced at the Olympic level by men and women over courses of 200, 500 and 1000 meters. Women compete on 1000 meters since 1997. World Championship events:
Olympic events (effective for 2012 Summer Olympics):
Flatwater racing kayaks are generally made out of extremely lightweight composites such as Kevlar, carbon fiber, or fiberglass. They are not intended for anything other than flat water. They are narrow, extremely unstable, and expensive. A competitive K1 or K2 runs in the USD–4,000 range. They require expertise to paddle well, but are fast in the hands of proficient users. The beam of a flatwater boat is typically barely wider than the hips of its paddlers, allowing for a long and narrow shape to reduce drag.
Due to their length (a K-1 is 5.2 meters (17 ft) and a K-2 is 6.2 meters (20 ft) long) sprint boats come equipped with a rudder to help with turning. The rudder is controlled by the feet of the paddler (the foremost paddler in multi–person designs). In spite of this, these boats have a fairly large turning radius.
Canoe sprint kayaks are closely related to sprint canoes, with both styles of boat usually at the same club or with the same team, although it is rare for paddlers to compete in both.
Downriver white water racers use a combination hull with a fast but unstable lower section similar to a flat water racer's hull, which flares into a wider section higher up, similar to a slalom hull, providing stability in big water.
A specialized variant of flatwater racing kayak called a Surf Ski has an open cockpit and can be up to 21 feet (6.4 m) long but only 18 inches (46 cm) wide, requiring expert balance and paddling skill. Surf Skis were originally created for surf and are still used in races in New Zealand, Australia, and South Africa. They have become popular in the United States for ocean races, lake races and even downriver races.
Slalom kayaks are flat–hulled, and—since the early 1970s—feature low profile decks. They are highly maneuverable, and stable but not fast in a straight line.
The term "kayak" increasingly applies to craft that look little like traditional kayaks.
Inflatables, also known as the ducky, can usually be transported by hand using a carry bag. They are made of hypalon (a kind of neoprene), Nytrylon (a rubberized fabric), pvc, or polyurethane coated cloth. They can be inflated with foot, hand or electric pumps. Multiple compartments in all but the least expensive increase safety. They generally use low pressure air, almost always below 3 psi.
While many inflatables are non-rigid, essentially pointed rafts, best suited for use on rivers and calm water, the higher end inflatables are designed to be hardy, seaworthy vessels. Recently some manufacturers have added an internal frame (folding-style) to a multi-section inflatable sit-on-top to produce a seaworthy boat.
The appeal of inflatable kayaks is their portability, their durability (they don't dent), and their easy storage. In addition, inflatable kayaks generally are stable, have a small turning radius and are easy to master, although some models take more effort to paddle and are slower than traditional kayaks.
A kayak with pedals allows the kayaker to propel the vessel with a propeller or underwater "flippers" rather than with a paddle. This allows the kayaker to keep hands free for steering, fishing and other activities.[7]
Traditional multi-hull vessels such as catamarans and outrigger canoes benefit from increased lateral stability without sacrificing speed, but these advantages cannot be successfully applied in all multi–hull kayaks. Outrigger kayaks attach one or two smaller hulls to the main hull to enhance stability, especially for fishing, touring and kayak sailing.
Twin–hull sit–on–top and sit–in kayaks have been on the market for many years. Inflatables are popular in whitewater and fishing applications.
While native people of the Arctic regions hunted rather than fished from kayaks, in recent years kayak sport fishing has become popular in both fresh and salt water, especially in warmer regions. Fishing kayaks are characterized by wide beams of up to 36 inches (91 cm) that increase lateral stability. Some are equipped with outriggers that are stable enough for paddling and fishing while standing. These kayaks are inexpensive and have few maintenance costs. Many kayak dealers have started customizing kayaks for fishing.
While paddling in the standing position has been practiced for centuries in canoes (including Umiaks, Pirogues, and native dugout canoes) recently kayakers have begun paddling while standing up. This is called striding, and involves paddling wide, inflatable kayaks down fast rivers while strapping both ankles to the kayak—similar to snow sports.
Kayaks were adapted for military use in the Second World War. Used mainly by British Commando and Special Forces, principally the Combined Operations Pilotage Parties (COPPs), the Special Boat Service (SBS, at that time an Army unit) and the Royal Marines Boom Patrol Detachment.
The latter made perhaps the best known use of them in the Operation Frankton raid on Bordeaux harbor.[8]
Following the war the SBS was reformed as a Royal Marines unit and the Klepper Aerius II folding kayak became a staple of its training and operations.
Kayaks made from thin wood sheathed in fiberglass have proven successful, especially as the price of epoxy resin has decreased in recent years. Two main types are popular, especially for the home builder: Stitch & Glue, and Strip-Built.
Stitch & Glue designs typically use modern, marine-grade plywood—quarter-inch 5 millimetres (0.20 in) thick. After cutting out the required pieces of hull and deck (kits often have these pre-cut), a series of small holes are drilled along the edges. Copper wire is then used to "stitch" the pieces together through the holes. After the pieces are temporarily stitched together, they are glued with epoxy and the seams reinforced with fiberglass. When the epoxy dries, the copper stitches are removed. The entire boat is then covered in fiberglass for additional strength and waterproofing. Construction is fairly straightforward, but because plywood does not bend to form curves, design choices are limited. This is a good choice for the first-time kayak builder as the labor and skills required (especially for kit versions) is considerably less than for strip-built boats.
Strip–-built designs are similar in shape to rigid fiberglass kayaks but are generally both lighter and tougher. Like their fiberglass counterparts the shape and size of the boat determines performance and optimal uses. The hull and deck are built with thin strips of lightweight wood, often Cedar, Pine or Redwood. The strips are edge-glued together around a form, stapled or clamped in place, and allowed to dry. Structural strength comes from a layer of fiberglass cloth and epoxy resin, layered inside and outside the hull. Strip–built kayaks are sold commercially by a few companies, priced USD 4,000 and up. An experienced woodworker can build one for about USD 400 in 200 hours, though the exact cost and time depend on the builder's skill, the materials and the size and design. As a second kayak project, or for the serious builder with some woodworking expertise, a strip–built boat can be an impressive piece of work. Kits with pre-cut and milled wood strips are commercially available.
Today almost all kayaks are commercial products intended for sale rather than for the builder's personal use. Nearly one of every three kayaks sold today is a sit–on–top (SOT), which is basically a paddleboard equipped with a seat.
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