Racing shells

In watercraft, a racing shell (also referred to as just a fine boat (UK) or just shell) is an extremely narrow, and often comparatively long, rowing boat specifically designed for racing or exercise. It is outfitted with long oars, outriggers to hold the oarlocks away from the boat, and sliding seats. The boat's long length and semicircular cross-section reduce drag to a minimum. This makes the boat both fast and unstable. It must be actively balanced by the rowers to avoid tipping. Being able to balance, or "set" the boat while putting maximum effort into the oars is therefore an essential skill of sport rowing.

The racing shell evolved from the simple working rowboat. Boats with longer hulls and narrower in beam were developed in the early 19th century specifically for team racing. These dedicated boats were the first boats that could be called racing shells, and they have since evolved into the highly specialized forms used today.

A narrower boat provides a sharper angle to the bow and a smaller cross-sectional area reducing drag and wave drag, and avoiding hull speed limitations at race speed. The first racing shells, while narrower than working rowboats, were limited by the width necessary to mount the oarlocks on the boat's sides ("gunwales"). By attaching outriggers to the gunwales, the oarlocks could be placed farther out, two things happened: oars got much longer, providing more length to the strokes, and hulls got narrower, until they were as narrow as it was possible while still retaining sufficient buoyancy and balance.

Originally made from lapstrake wood, shells are now almost always made from a composite material for strength and weight advantages. The first composite shells were made from a form of papier-mâché and became popular in the 1870s. These paper shells were sold world-wide by the Waters Paper Boat Factory of Troy, New York. Modern shells are usually made of carbon-fibre reinforced plastic in a honeycomb structure. They are manufactured by either cold laying up of the carbon, which is then left to set, or by using heat curing, which ensures that the carbon fibre composite is properly set. The best shells are characterized by their "stiffness", as the lack of flexing means none of the force exerted by the rower is wasted in twisting the boat.

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Wikipedia