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| Connecticut Water Trails Association |
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Connecticut Water Trails Program Canoe Basics
How To Choose A Canoe -
Elements of Performance
Length
It is a question of physics. But you don't have to
be a whiz in physics to understand that a narrow and longer hull
generates less friction against the water and is easier to paddle. Some people say that the center half of a
well-designed hull provides 75% of its stability and carrying capacity.
The primary function of the bow and stern if to part the water at the
entry and the exit. In most cases, the greater the waterline length and the higher the ratio of length to width, the faster the canoe will go and the easier it will be to paddle. It is also said that the maximum speed equals 4.5
times the square root of the waterline length in depth water.
Hull Shape The hull views gives you an indication of the watercraft's utility. Was it built primarily to be used on a lake, a flat river, or in whitewater? Can the canoe be used for trips, wilderness waters, or just for daily recreation? We all know that a canoe can be used for many purposes - it is a versatile craft - but if you think your canoe will be used primarily for a specific need, why not get immediately a canoe for this need? It is important to understand how a rounded-bottom and a flat-bottom canoe behave in waves and their overall stability.
Even if you're not an expert, you will certainly
appreciate the subtle changes of these basic forms. The way the
hull of a canoe is built has a major impact on speed, load,
maneuverability, tracking in water and stability.
Profile View The figures shown below span two extremes, from an
extreme rocker canoe to a straight keel line canoe.
Even if you're not an expert, you will certainly
appreciate the subtle changes of these basic forms. The way the
hull of a canoe is built has a major impact on speed, load,
maneuverability, tracking in water and stability.
As previously mentioned, each constituent in the
design has an impact on the maneuverability, speed, tracking, stability
and ease of paddling of the craft. For example, if you select an extreme rocker canoe,
which will give you optimal maneuverability, you will sacrifice tracking
and speed. Let's now discuss some canoe elements that can be
seen on the profile view above. Keel Line In looking at the keel line of a canoe, you can have
a good idea of its maneuverability, its speed and tracking. If you
imagine that you have a horizontal line at midpoint four (4) inches (10
cm) over the keel line that will give you an estimate of the waterline
length. An optimal waterline should give more speed and tracking even if
it has a high friction on water because the draught (traction) will be
minimized but less maneuverability to turn quickly in every direction
(except for a flat bottom hull). However, a rocker keel line will do the
opposite because the water line length will be shorter (see Figures
above), which means, more maneuverability, less speed and tracking. A
rocker keel line canoe is mainly used in whitewater because its shorter
waterline helps to turn on its midpoint and rises over waves (See
Rocker).
Keel or Not?? The keel is a subject of high controversy for the canoeist and manufacturers. We don't really think it helps tracking and maneuverability to an intermediate or experienced canoeist. It can maybe help a novice paddler on a wave less lake or quiet river. Furthermore, some people unfamiliar with a canoe, believe it helps stability for not keeling over. This statement is completely false. The main purposes of a keel are to stiffen and give some protection to the hull. But this has little impact when you cross a sandbank or a shallow. An aluminum canoe, as an example, is usually made in two (2) parts, and then the keel is necessary to keep parts together. As a keel can affect the maneuverability of a canoe,
we recommend using a canoe without a keel for high running water or
whitewater. Rocker The rocker is the longitudinal curve of the keel line from bow to stern. A canoe with a high rocker (see also keel line) can easily turn at midpoint and rise over waves. It is then an excellent choice for whitewater. However, it will be a poor choice for flat water because it will be slow (no waterline length) and difficult to track in straight-line. Before choosing a canoe, you should take into consideration the following: A canoe of 15 feet (4.5 meters) or less needs less rocker. The rocker should not exceed 1,5 inches (3.8 cm). A canoe more than 15 feet (4.5 meters), usually used for light tripping and recreation, needs more rocker then a short canoe. The rocker should not exceed 3 inched (7.6 cm). A canoe mainly used for running river or whitewater can have more
rocker than the former.
Stem Shape Many people prefer having a high-recurved stem
because it is graceful and eye appealing. It is a matter of personal
preference. Never forget that a high-recurved stem offers a large wind
surface, which can affect the tracking or maneuverability of a canoe
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