I see early tris Piver etc seem to have essentially triangular sections and often no or very small keels centreboards - presumably the sharp hull form provides sufficient sideways resistence in this case.

Trimaran hull shape. It also adds to the interior room especially at shoulder level. 5 ft 6 in Displacement. The outlines of cross sections 919 change gradually.

The effectiveness of this hull shape is ideal for cruising cats as well as racing boats and we have been using it on a wide range of designs including the new Raku series of cats. As for original hull the outlines of cross sections 08 are composed of two straight lines and the width of the knuckle line is the same. So fine hulls are only an advantage if your boat is light and has enough sail area to ensure youre travelling at speeds where form resistance is greater than skin resistance.

LEEN hulls A specially developed design for high-performance vessels. 30 ft 10 in Beam. The Shuttle 39 is a high performance trimaran designed for offshore sailing and fast cruising.

Hull length-to-beam ratio LwlBh This ratio is the measure of hull slimness at the waterline which is significant for performance. However in more modern tris the hull forms seem to get more rounded. Optimization of the hull shape increases hull efficiency and speed of a vessel.

Amas are the outer hulls of a trimaran sometimes referred to as outriggers or the smaller hull of a proa. 1 ft 4 in Maximum Draft. If we widen the hull at the bottom the sides can become more vertical and this more box-like section can further lower the wave-making compared to the Vee-section we started out with as it.

22 ft 5 in LWL. 6 ft 2 in Dry Weight. This means that its Lb Length to waterline beam ratio will typically be up in the 7 to 10 range and with a cruising tri often needs to spread out on both sides above the.