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Revision as of 14:48, 1 October 2007

Template:Two other uses

A wood-and-canvas canoe evokes the heritage of canoeing in North America.

A canoe is a small narrow boat, typically human-powered, but also commonly sailed. Canoes usually are pointed at both bow and stern and are normally open on top, but can be covered.

In its human-powered form, the canoe is propelled by the use of paddles, with the number of paddlers depending on the size of the canoe (most commonly two). Paddlers face in the direction of travel, either seated on supports in the hull, or kneeling directly upon the hull. In this way paddling a canoe can be contrasted with rowing, where the rowers face away from the direction of travel. Paddles may be single-bladed or double-bladed.

Sailing canoes (see Canoe Sailing) are propelled by means of a variety of sailing rigs. Common classes of modern sailing canoes include the 5m² and the International 10m² Sailing canoes. The latter is otherwise known as the International Canoe, and is one of the fastest and oldest competitively sailed boat classes in the western world. The log canoe of the Chesapeake Bay is in the modern sense not a canoe at all, though it evolved through the enlargement of dugout canoes.

Design and construction

Parts of a canoe

View of a typical canoe from above
View of a typical canoe from above
  1. Bow
  2. Stern
  3. Hull
  4. Seat (whitewater canoes may have a foam 'saddle' in place of a seat)
  5. Thwart - a horizontal crossbeam near the top of the hull
  6. Gunwale (pronounced gunnel) - the top edge of the hull
  7. Deck (under which a flotation compartment or foam block may be located which prevent the canoe from sinking if capsized or swamped)

Optional features in modern canoes (not shown in diagram):

  1. Yoke - a thwart across the center of the boat to allow one person to carry the canoe, and is sometimes molded to the shape of the shoulders.
  2. Keel - runs along the bottom of the canoe's hull, from the bow to the stern, serving as the foundation or spine of its structure and, depending on its depth, provides some directional control and stability.
  3. Flotation bags - inflatable air bags to prevent swamping the canoe in rapids
  4. Spraydeck - cover to prevent water entering the canoe

The portion of the hull between the waterline and the top of the gunwale is called freeboard.

Canoe materials

A Malecite birchbark canoe built by Henri Vaillancourt, who was made famous by John McPhee in his book, Survival of the Bark Canoe

The earliest canoes were made from natural materials:

  • Early canoes were wooden [1], often simply hollowed-out tree trunks (see dugout). This technology is still practiced in some parts of the world. Modern wooden canoes may be wood strip (also, "stripper"), wood-and-canvas, stitch-and-glue, glued plywood lapstrake, or birchbark built by dedicated artisans. Such canoes can be very functional, lightweight, and strong, and are frequently quite beautiful works of art.
  • Many indigenous peoples of the Americas built canoes of tree bark, sewn with tree roots and sealed with resin. The indigenous people of the Amazon commonly used Hymenaea trees. In temperate North America, white cedar was used for the frame and bark of the Paper Birch for the exterior, with charcoal and fats mixed into the resin. A few modern canoe builders have revived and continued building birchbark canoes, including Henri Vaillancourt and Tom MacKenzie.

Modern technology has expanded the range of materials available for canoe construction.

  • Wood-and-canvas canoes are made by fastening an external waterproofed canvas shell to a wooden hull formed with white cedar planks and ribs. These canoes evolved directly from birchbark construction. The transition occurred in the 19th century, first, in Ontario, when canoe builders laid canvas instead of bark into a traditional building bed and, later, in Maine, when builders adapted English boat-building inverted-forms technology. In areas where birchbark either was scarce or where demand exceeded ready supply, other materials, such as canvas, had to be used as there had been success in patching birchbark canoes with canvas or cloth. Efforts were made in various locations to improve upon the bark design such as in Peterborough, Ontario, Canada where rib-and-plank construction was used by the Peterborough Canoe Company, and in Maine, in the U.S, where similar construction was used by various companies. Maine was the location of the development of commercial wood-and-canvas canoes. E. H. Gerrish, of Bangor, is now recognized as the first person to produce wood-and-canvas canoes commercially, but other Maine builders soon followed, including, B. N. Morris, of Veazie, E. M. White, of Old Town, and, of course, the Gray family of the Old Town Canoe Co. In the adjoining Canadian province of New Brunswick, from the late 1800s until being disbanded in 1979, the Chestnut Canoe Company, along with the Old Town Canoe Company in Maine, became the pre-eminent producers of wood-and-canvas canoes. American President Teddy Roosevelt purchased Chestnut canoes for a South American expedition. Wood-and-canvas canoes have undergone a resurgence in recent years, spurred in part by the Wooden Canoe Heritage Association [2]. Builders abound, including Jerry Stelmok, Rollin Thurlow, Ken Solway, Joe Seliga, and many others [3].
  • Aluminum canoes were first made by the Grumman company in 1944, when demand for airplanes for World War II began to drop off. Aluminum allowed a lighter and much stronger construction than contemporary wood technology. However, a capsized aluminum canoe will sink unless the ends are filled with flotation blocks. Moreover, an aluminum canoe is extremely noisy, rendering it unsuitable for viewing wildlife.
  • Plywood canoes are "stitched" together using cable-ties or copper wire, sealed with epoxy resin, or the inferior but cheaper polyester resin, and reinforced with glass fiber tape or cloth.
  • Composites of fiberglass, Kevlar and carbon fiber are used in synthetic canoe construction. Developed over 50 years ago, these materials are light, strong, and maneuverable. Easily portaged, these canoes allow experienced paddlers access to remote wilderness areas.
  • Acrylonitrile butadiene styrene or ABS , trademarked as "Royalex," is another synthetic composite material that makes an extremely flexible and durable hull. It is suitable, in particular, for whitewater canoes. ABS canoes have been known to pop back into their original shape with minimal creasing of the hull after having been wrapped around a rock in strong river currents.
  • Polyethylene is a cheaper and heavier material used for synthetic canoe construction with the benefit of superior abrasion resistance, primarily found in whitewater canoes.

Depending on the intended use of a canoe, the various kinds have different advantages. For example, a wood-and-canvas canoe is more fragile than an aluminum canoe, and thus less suitable for use in rough water; but it is much quieter — thus better for observing wildlife. However, canoes made of natural materials require regular maintenance without which they lack durability. A Kevlar canoe is tough and also light, good for wilderness tripping. Modern hybrids can combine the elgance and style of traditional wooden canoes with such benefits as modern materials can provide.

Shape

Many canoes are symmetrical about the centerline, meaning their shape can be mirrored along the center. When trimmed level (rarely the case) they should handle the same whether paddling forward or backward. Many modern designs are asymmetrical, usually having the widest beam slightly farther aft which improves efficiency and promotes more level fore and aft trim. A further improvement may be found in canoes with a straighter hull profile aft and rocker forward which improves tracking.

A traditionally shaped canoe, like a voyageur canoe, will have a tall rounded bow and stern. Although tall ends tend to catch the wind, they serve the purpose of shedding waves in rough whitewater or ocean travel.

Some canoes are made with squared sterns — "Y", "V", or "U" shaped — in order to permit the mounting of outboard motors. Very large freighter canoes can be powered with powerful motors, but canoes that are 18-feet-long or shorter would normally be propelled by motors of 3 horsepower or less. Side brackets can be mounted on canoes with pointed sterns to mount small outboard motors of about 1½-to-2 horsepower, which propel such canoes with surprising speed.

Cross section

The shape of the hull's cross section significantly influences the canoe's stability under differing conditions. Flat-bottomed canoes generally have excellent initial stability, which diminishes rapidly with increased heel. Their high initial stability causes them to have a more abrupt motion in waves from the side.

For a given beam, a rounded-bottom canoe will have less initial stability than its flatter bottomed cousin. Round sections have lower surface area for a given volume and have less resistance through the water. They are most often associated with racing canoes.

In between the flat and rounded bottom are the more common shallow-arc and "V" bottom canoes which provide a compromise between performance and stability. The shallow-vee bottom, where the hull centerline forms a ridge like a shallow "V", will behave similar to a shallow-arc bottom but its volume to surface ratio is worse.

Similar is the tumblehome hull which has the top potion of the hull curving back in slightly.

Many modern canoes combine a variety of cross sections to suit the canoe's purpose.

Keels

Keels on canoes improve directional stability (the ability to 'track' in a straight line) but decrease the ability to turn quickly. Consequently, they are better suited for lake travel, especially when traveling on open water with crosswinds. Conversely, keels and "Vee"-bottoms are undesirable for whitewater because often quick turns are required.

In aluminum canoes, small keels occur as manufacturing artifacts when the two halves of the hull are joined. In wood-and-canvas canoes, keels are rub-strips to protect the boat from rocks and as they are pulled up on shore. Plastic canoes feature keels to stiffen the hull and allow internal tubular framing to lie flush with the sole of the canoe.

Rocker

Curvature of the hull profile that rises up at the bow and stern is called "rocker". Increasing the rocker improves maneuverability at the expense of tracking. Specialized canoes for whitewater play have an extreme rocker and therefore allow quick turns and tricks. Rocker also has an immense effect on the stability of a Canadian canoe. By lifting the ends of the craft out of the water, rocker puts more of the wider center section of the boat into the water, contributing significantly to the overall stability of the craft. 35mm rocker at each end makes all the difference to how safe a novice will feel in a canoe.

Gunwales

Modern cedar-strip canoes have gunwales which consist of an inner and outer parts called "inwales" and "outwales". These two parts of the gunwale give rigidity and strength to the hull. The inwale will often have "scuppers" or slots cut into the inwale to allow water to drain when the canoe hull is turned upside down for storing.

Types of canoes

In the past, people around the world have built very different kinds of canoes, ranging from simple dugouts to large outrigger varieties. More recently, technologically advanced designs have emerged for particular sports.

Traditional designs

Early canoes have always incorporated the natural materials available to the local people. The different canoes (or canoe like) in many parts of the world were:

Modern designs

Modern canoe types are usually categorized by the intended use. Many modern canoe designs are hybrids (a combination of two or more designs, meant for multiple uses). The purpose of the canoe will also often determine the materials used. Most canoes are designed for either one person (solo) or two persons (tandem), but some are designed for more than two persons.

  • Touring canoe (or tripping canoe) In North America, a "touring canoe" is a straight tracking boat good for wind blown lakes etc. A "tripping canoe" has a larger capacity for wilderness travel and is designed with more rocker for better maneuverability on whitewater rivers but requiring some skill on the part of the canoeist in open windy waters, when lightly loaded. Often made of lighter materials and built for comfort and cargo space; usually a more traditional design.
  • Prospector canoe - A generic name for copies of the famed Chestnut model, a popular type of tripping canoe marked by a symmetrical hull and a relatively large amount of rocker; giving a nice balance for wilderness tripping, of the ability to carry large amounts of gear whilst being maneuverable enough for whitewater. This makes it a superb large capacity wilderness boat, but requires skill on windy, broad waters when lightly loaded. Made in a variety of materials. For home construction, 4mm plywood is commonly used, mainly marine ply, using the "stitch and glue" technique. Commercially built canoes are commonly built of fibreglass, HDPE, Kevlar, Carbon Fiber, and Royalex which is although relatively heavy, very durable.
  • Long Distance Touring canoe - A cockpit has many advantages: the gunwale can be made lower and narrower so the paddler can reach the water more easily, and the rim of the boat can be higher keeping the boat dryer. With a rounded hull shape and full ends there is less for turbulent water to work on.
  • Whitewater canoe (or river canoe) - typically made of tough man-made materials, such as ABS or Kevlar, for strength; no keel and increased rocker for maneuverability; often extra internal lashing points are present to secure flotation bags, harness, and spraydeck. Some canoes are decked and look very much like a kayak, but are still paddled with the paddler in a kneeling position and with a single bladed paddle.
  • Playboating open canoe - a subgroup of whitewater canoes specialized for whitewater play and tricks or for competitive whitewater slalom. Some of these canoes are short in length and have such extreme rocker that they are also known as banana boats.
  • Square stern canoe - asymmetrical canoe with a squared off stern for the mounting of an outboard motor; meant for lake travel or fishing.
  • Racing canoe (or sprint canoe) - purpose-built racing canoe for use in racing on flat water. To reduce drag, they are built long and with a narrow beam, which makes them very unstable. A one-person sprint canoe is 5.2 meters or 17 feet long. Sprint canoes are paddled kneeling on one knee, and only paddled on one side; in a C-1, the canoeist will have to j-stroke constantly to maintain a straight course. Marathon canoe races use a similar narrow boat.
  • Inflatable canoe - similar in construction and materials to other inflatable boats but shaped like a canoe. It is meant for serious whitewater and is usually difficult to use for flat water travel.

Differences from other paddled boats

  • Kayak - A kayak differs from a canoe in that the kayak typically has a covered deck (an extension of the hull), a cockpit covered by a water-tight spraydeck, and is propelled by a sitting paddler with a double-bladed (one on each end) paddle (most canoers use a single bladed paddle). A double-bladed paddle allows for more efficient propulsion (fewer correction strokes, etc.), but is more difficult to use effectively in a wider craft (canoes tend to be wider than kayaks). The spraydeck (also known as a skirt) is used to seal the gap between the deck and the paddler, making it possible to recover from a capsize without flooding the interior of the hull with water.
  • Rowboat - Not considered a canoe. It is propelled by oars resting in pivots on the gunwales or on 'riggers' that extend out from the boat. A rower may use one (sweep-oar) or two oars (sculling). A rower sits with his or her back toward the direction of travel. Some rowboats, such as a McKenzie River dory or a raft outfitted with a rowing frame are suitable for whitewater.
  • Adirondack guideboat - a rowboat that has similar lines to a canoe. However the rower sits closer to the bilge and uses a set of pinned oars to propel the boat.
  • Dragon boat - while it handles similar to and is paddled the same way as a large canoe, a dragon boat is not considered a canoe since its construction is markedly different.

Use

Canoes have a reputation for instability, but this is not true if they are handled properly. For example, the occupants need to keep their center of gravity as low as possible. Canoes can navigate swift-moving water with careful scouting of rapids and good communication between the paddlers.

When two people occupy a canoe, they paddle on opposite sides. For example, the person in the bow (the bowman) might hold the paddle on the port side, with the left hand just above the blade and the right hand at the top end of the paddle. The left hand acts mostly as a pivot and the right arm supplies most of the power. The sternman would paddle to starboard, with the right hand just above the blade and the left hand at the top. For travel straight ahead, they draw the paddle from bow to stern, in a straight line parallel to the gunwale.

Tandem Canoe Steering

The paddling action of two paddlers will tend to turn the canoe toward the side opposite that on which the stern paddler is paddling. Thus, steering is very important, particularly because canoes have flat-bottomed hulls and are very responsive to turning actions. Steering techniques vary widely, even as to the basic question of which paddler should be responsible for steering.

Among experienced white water canoeists, the stern paddler is primarily responsible for steering the canoe, with the exception of two cases: The bow paddler will steer when avoiding rocks and other obstacles that the stern paddler cannot see. Also, in the case of back ferrying, the bow paddler is responsible for steering the canoe using small correctional strokes while back paddling with the stern paddler.

Among less-experienced canoeists, the canoe is typically steered from the bow. The advantage of steering in the bow is that the bow paddler can change sides more easily than the stern paddler. Steering in the bow is initially more intuitive than steering in the stern, because to steer to starboard, the stern must actually move to port. On the other hand, the paddler who does not steer usually produces the most forward power or thrust, and the greater source of thrust should be placed in the bow for greater steering stability.

Paddle strokes

Paddle strokes are important to learn if the canoe is to move through the water in a safe and effective manner. Categorizing strokes makes learning them easier. After the strokes are mastered, they can be combined or modified so that maneuvers are accomplished in an efficient, effective, and skillful manner. Here are the primary strokes:

  • The cruising stroke or forward stroke is the easiest stroke and is considered to be the foundation of all the other strokes. The paddle blade is brought forward along the side of the canoe, dipped into the water, and drawn back. The paddle should be drawn straight back rather than following the gunwale's curvature. In a tandem canoe, it is used mainly by the bowman to simply propel the canoe forward without turning.
  • The back stroke is essentially the same movement as the forward stroke, but done in reverse. The back face of the blade is used in this case. This stroke is used to make the canoe go backward or to stop the canoe.
  • The J-stroke is so named because, when done on the port side, it resembles the letter J. It begins like a standard stroke, but towards the end the paddle is rotated and pushed away from the canoe with the power face of the paddle remaining the same throughout the stroke. This conveniently counteracts the natural tendency of the canoe to steer away from the side of the stern man's paddle. Advocates of steering in the stern of tandem canoes often use this stroke, and it is also used in reverse by the bowman while backpaddling or back ferrying in white water.
  • The Superior stroke is a less elegant but more effective stroke which is used in the stern of tandem canoes. It is more commonly referred to as the goon or rudder stroke. Unlike the J-stroke in which the side of the paddle pushing against the water during the stroke (the power face) is the side which is used to straighten the canoe, this stroke uses the opposite face of the paddle to make the steering motion. It is somewhat like a stroke with a small pry at the end of it. This stroke uses larger muscle groups, is preferable in rough water and is the one used in white water. It is commonly thought to be less efficient than the J-stroke when paddling long distances across relatively calm water.
  • The Indian stroke may be used to paddle a straight course like the J. It can be useful against strong winds or running rapids. Move the paddle forward, rotate the grip of the paddle in the palm of your upper hand. Then you are ready for the next power stroke without taking the blade out of the water. If done carefully, there is no sound from the paddle, making it possible to paddle in calm water without sound.
  • The pry stroke begins with the paddle inserted vertically in the water, with the power face outward, and the shaft braced against the gunwale. A gentle prying motion is applied, forcing the canoe in the opposite direction of the paddling side.
  • The push-away stroke has an identical purpose to the pry stroke, but is performed differently. Instead of bracing the paddle against the gunwale, the paddle is held vertically, as in the draw stroke, and pushed away from the hull. This is more awkward and requires more force than the pry, but has the advantage of preventing damage to the paddle and canoe due to rubbing on the gunwale. It also uses force more efficiently, since the paddle is pushing straight out, instead of up and out.
  • The running pry can be applied while the canoe is moving. As in the standard pry, the paddle is turned sideways and braced against the gunwale, but rather than forcing the paddle away from the hull, the paddler simply turns it at an angle and allows the motion of the water to provide the force.
  • The draw stroke exerts a force opposite to that of the pry. The paddle is inserted vertically in the water at arm's length from the gunwale, with the power face toward the canoe, and is then pulled inward to the paddler's hip. A draw can be applied while moving to create a running or hanging draw. For maximum efficiency, if multiple draw strokes are required, the paddle can be turned 90° and sliced through the water away from the boat between strokes. This prevent the paddler from having to lift the paddle out of the water and replace it for each stroke.
  • The scull, also known as a sculling draw is a more efficient and effective stroke where multiple draw strokes are required. Instead of performing repeated draw strokes, the paddle is "sculled" back and forth through the water. Beginning slightly in front of the paddler, the paddle is angled so that the power face points at a 45° angle toward the hull and astern. The paddle is drawn straight backward, maintaining the angle, and then the angle is rotated so that the power face is pointing 45° toward the hull and the bow. The paddle is pushed straight forward, and the whole process is repeated. The net effect is that the paddler's end of the canoe is drawn toward the paddling side.
  • The reverse scull (sometimes sculling pry or sculling push-away) is the opposite of the scull. The stroke is identical, but with the paddle angles reversed. The net effect is that the paddler's end of the canoe is pushed away from the paddling side.
  • The cross-draw stroke or cross-bow draw is a stroke that exerts the same vector of force as a pry, by moving the blade of the paddle to the other side of the canoe without moving the paddler's hands. The arm of bottom hand crosses in front of the bowman's body to insert the paddle in the water on the opposite side of the canoe some distance from the gunwale, facing towards the canoe, and is then pulled inward while the top hand pushes outward. The cross-draw is much stronger than the draw stroke, but normally can't be used by the stern paddler in a tandem canoe.
  • The sweep is unique in that it steers the canoe away from the paddle regardless of which end of the canoe it is performed in. The paddle is inserted in the water some distance from the gunwale, facing forward, and is drawn backward in a wide sweeping motion. The paddler's bottom hand is choked up to extend the reach of the paddle. In the case of the bowman, the blade will pull a quarter-circle from the bow to the paddler's waist. If in the stern, the paddler pulls from the waist to the stern of the canoe. Backsweeps are the same stroke done in reverse.

In tandem canoes, complementary strokes are selected by the bow and stern paddlers in order to safely and quickly steer the canoe. It is important that the paddlers remain in unison, particularly in white water, in order to keep the boat stable and to maximize efficiency.

There are some differences in techniques in how the above strokes are utilized.

  • One of these techniques involves locking or nearly locking the elbow, that is on the side of the canoe the paddle is, to minimize muscular usage of that arm to increase endurance. Another benefit of this technique is that along with using less muscle you gain longer strokes which results in an increase of the power to stroke ratio. This is generally used more with the 'stay on one side' method of paddling.
  • The other technique is generally what newer canoeists use and that is where they bend the elbow to pull the paddle out of the water before they have finished the stroke. This is generally used more with the 'switch sides often' method of paddling.
  • The stay on one side method is where each canoeist takes opposite sides and the stern man uses occasional J-strokes to correct direction of travel. The side chosen is usually the paddlers' stronger side, since this is more comfortable and less tiring. Some canoeists do, however, switch sides after twenty to thirty minutes or longer as a means of lessening muscle fatigue.
  • The switch sides often method (also called hit and switch, hut stroke, or Minnesota switch) allows the canoeists to switch sides frequently (usually every 5 to 10 strokes, on a vocal signal, commonly "hut") to maintain their heading. This method is the fastest one on flat water and is used by all marathon canoeists in the US and Canada. The method works well with bent-shaft paddles. Racer/designer Eugene Jensen is credited with the development of both "hit and switch" paddling and the bent shaft paddle [citation needed].

Setting poles

On swift rivers, the stern man may use a setting pole. It allows the canoe to move through water too shallow for a paddle to create thrust, or against a current too quick for the paddlers to make headway. With skillful use of eddies, a setting pole can propel a canoe even against moderate (class III) rapids.

Gunwale bobbing

A trick called "gunwale bobbing" or "gunwaling" allows a canoe to be propelled without a paddle. The canoeist stands on the gunwales, near the bow or the stern, and squats up and down to make the canoe rock backward and forward. This propulsion method is inefficient and unstable; additionally, standing on the gunwales can be dangerous. However, this can be turned into a game where two people stand one on each end, and attempt to cause the other to lose balance and fall into the water, while remaining standing themselves.

Image gallery

External links

References

  • The Canoe, Its Selection, Care, and Use, The Macmillan Company, New York, 1914, by Robert E. Pinkerton
  • The Bark Cannoes and Skin Boats of North America, Smithsonian Institution Press, Washington, D.C., 1983, by Edwin Tappan Adney and Howard I. Chapelle
  • Pole, Paddle, & Portage, Van Nostrand Reinhold, New York, 1969, by Bill Riviere
  • The Complete Wilderness Paddler, ISBN 0-394-49347-8, by James West Davidson and Jon Rugge
  • North American Canoe Country, Macmillan Company, Toronto, 1964, by Calvin Rutstrum
  • Building the Maine Guide Canoe, ISBN 0-87742-120-X, by Jerry Stelmok
  • The Wood & Canvas Canoe, ISBN 0-88448-046-1, by Jerry Stelmok and Rollin Thurlow
  • The Survival of the Bark Canoe ISBN 0-374-27207-7, by John McPhee
  • Path of the Paddle ISBN 1-55209-328-X, by Bill Mason
  • Song of the Paddle ISBN 1-55209-089-2, by Bill Mason
  • Thrill of the Paddle ISBN 1-55209-451-0, by Paul Mason