### Glossary of Terms

Beam: This is always taken at the widest point of the hull at the Load Waterline and should not be confused with arbitrary measurements such as 3-inch waterlines, which are meaningless in terms of hull resistance.

Beam/Draft Ratio: Beam divided by the draft.

Coefficient of Friction: A constant varying with the speed, length of surface and condition of surface. This is usually determined experimentally and applied as if it was constant over the full length of the hull. It isn't, of course, but the difference is slight.

Deadwood: Profile area below the waterline at the bow and stern.

Designed Displacement: This is the displacement at which the canoe is intended to be loaded for best performance at its intended purpose.

Displacement: The total weight of the canoe, passengers and gear.

Displacement/Length Ratio (D/L): The displacement in long tons (2240 lbs.) divided by (.01 x length)^3. This is a measure of the "fineness" of the hull. It produces an easily handled number that facilitates comparison of a variety of hull shapes.

Frictional Resistance (Rf): Resistance caused by the passage of water across the hull surface.

Laminar Flow: Apparently random flow that is not random but defies our ability to analyze it at this time.

Longitudinal Co-efficient (Cl): A measure of the distribution of volume along the hull's length determined by dividing the volume displacement by the volume of a parallel-sided solid having the same maximum section and waterline length. This is sometimes called the Prismatic Co-efficient.

Mid-Ship Section Co-Efficient (Cx): The area of the largest hull section divided by a rectangular section having the same beam and draft. This is a measure of the section fullness that provides easy comparison between hulls of difference sizes.

Residual Resistance (Rr): All resistance affecting a body's motion through the water excepting friction.

Section: The shape of a place passing through the hull normal to the centerline.

Section Coefficient: The ratio of the area of a section divided by the area of a rectangular section having the same beam and draft. It is a measure of the relative fullness of a section, and permits the comparison of hulls of differing sizes and shapes.

Speed/Length Ratio: The velocity (usually in knots) divided by the square root of the length in feet. This ratio permits the performance comparison of hulls of differing lengths.

Turbulent Flow: Apparently random flow that is not random but defies our ability to analyze it at this time.

Volume (Vp): Volume of the parallel-sided solid used in determining the Longitudinal Co-efficient.

Waterline Beam: The beam at the waterline when loaded at the Designed Displacement.

Wetted Surface: That part of the hull in contact with the water when the hull is loaded to its Designed Displacement.

Yaw: The angle of the hull centerline relative to the true course of the hull.