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Reach (sailing NA)

B1. Naval Architecture

Definition

Geometric parameter in stability calculations.

Reaching is the point of sail with the apparent wind roughly on the beam, between close-hauled and running, the band over which a sailing yacht develops the most driving force and reaches its highest boat speeds. The reaching arc divides into a close reach (apparent wind forward of the beam), a beam reach (apparent wind abeam), and a broad reach (apparent wind abaft the beam). The sails work partly as lifting foils and partly as drag surfaces across this arc, and the apparent wind shifts forward as the boat accelerates because boat velocity adds to true wind in the apparent-wind triangle. Heeling force and the matching side force on the lateral plane are largest on a beam reach.

Source: Marchaj, Aero-Hydrodynamics of Sailing