CANOE Design the Elements of
The shape of a canoe defines its per-
formance characteristics and every canoe is a blend of individual elements brought together in one design. Any design incorporates an innumerable number of variables blended to pro- duce a canoe that meets a number of specific needs such as stability for bird- ing, manoeuvrability for whitewater or speed for marathon racing. Complicated? At a detailed level yes, truly
scientific.The basics,however, are not.
Length = Speed The overall performance of a canoe is most
affected by the length and width of the hull. Length is the primary factor in determining speed. Given two canoes of different lengths, with all other specifications the same, the longer canoe will be faster. It will also track bet- ter (tracking means going in a straight line), and have a greater potential for carrying more gear. Shorter canoes will be more manoeu- vrable, making them easier to turn, and will generally be lighter in weight.
Width + Cross Section = Stability Width is the primary factor in determining
stability. A wider canoe will be more stable. Width (beam as it is called) is given in two measurements: the beam at the gunwale and the beam at the four-inch waterline. The four- inch waterline beam has the greatest influence on performance because this area forms the footprint of the boat—or rather, the width of the boat actually in the water. Wide beamed canoes offer great stability but are slower. Narrow canoes may be less stable but afford
better efficiency through the water allowing for greater speed. Stability is often divided into initial (or pri-
mary) and final (or secondary). Initial stability is what you feel when you first get into the boat. If the boat feels unstable it probably has less pri- mary stability than a boat you’d feel comfort- able standing up and walking around in. Secondary stability refers to how difficult the boat is to actually tip over, or if you prefer, the resistance the boat has to capsizing. The shape of the bottom of the canoe and how it blends with the sides will influence its perform- ance. Stability of a canoe, while influenced by overall width is also affected greatly by its cross section. Flat bottom canoes offer great initial stabili-
ty. They feel very secure on calm water. Flat bottom canoes are great for the sportsmen and general recreationalists looking for the feeling of steadiness. But if tilted, this type of hull will quickly upset without much warning. Shallow arch or shallow V bottomed canoes have less initial stability but good secondary stability. As the canoe is tilted over, it balances on its side and resists further tipping. Shallow arch canoes work well in waves and whitewa- ter. Shallow arch bottomed canoes offer good all-around performance. Round bottomed canoes have even greater
secondary stability but very little initial stability. They are designed for speed and efficiency. Round bottom canoes are usually fast, spe- cialised canoes designed for competitive rac- ing.
A keel is a ridge or attached piece of mate- rial that runs the length of the keel line on the outside of the boat. It helps the canoe track and is often found on short, wider canoes. Keels help the canoe resist the influence of crosswinds. They also increase the overall drag of the boat reducing hull speed. Flare sheds water reducing the amount of water sloshing over the gunwales. Tumblehome gives a narrower beam at the
gunwales making it easier for the paddler to reach over the side of the canoe when pad- dling. Straight-sided canoes are a balance between the paddling efficiency of tumble- home and the dryness of flare. Canoe designs will incorporate one, two, or all three of these in different areas of the hull offering the advan- tages of each in appropriate areas on the hull.
Depth = Capacity and Dryness Depth refers to the distance between the bottom of the hull and the top of the gunwale. Canoe manufacturers may provide the depth at the bow, stern and centre of the boat. The amount of depth influences the freeboard. Freeboard is the amount of canoe above the waterline. Greater depth allows for increased carrying capacity and better water shedding ability in part because the amount of freeboard remains within an acceptable limit. Deeper
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