Chines

Defining the angle where the bottom meets the sides
When the side of a boat meets the bottom at a well-defined angle, rather than a rounded section, the

An early Ray Hunt–designed deep-V, the smoothest-riding planing boat of its day. Modern refinements missing here include chine flats and a padded keel, which would add form stability and planing efficiency. This hull became an early Bertram and is the paradigm for all modern planing hulls.

A Viking 52 profile with selected stations showing the change in shape from bow to stern. Viking uses double chines, which, when on plane at high speeds, reduce wetted surface by effectively narrowing the beam.

resultant “corner” is known as the chine. The more abrupt the angle, the harder is the chine.In a boat with a flat or V-bottom, the chine coincides with the turn of the bilge. Instead of one hard chine, a boat may have two or more softer chines, in which case it is known as a multichine hull.Chine construction is particularly suitable for building with metal or plywood, resulting in perfectly seaworthy craft, although to some they are not as pleasing to the eye as traditional round-bilged boats. Many small pram dinghies are also of hard-chine design, not only for ease of construction, but also because hard chines add greatly to stability. Some modern powerboats have deep-V designs featuring rows of thin longitudinal chines to give them a softer ride at high speed in choppy seas.See also Bilge.

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