A spinnaker is a special type of
sail that is designed specifically for
sailing off the wind from a reaching course to a downwind, i.e. with the wind 90°–180° off the bow. The spinnaker fills with wind and balloons out in front of the boat when it is deployed, called flying. It is constructed of very lightweight, usually
nylon, fabric, and is often brightly colored. It may be optimised for a particular range of wind angles, as either a reaching or a running spinnaker, by the shaping of the panels and seams. The spinnaker is often called a kite, or a chute (as in cruising chute) because it somewhat resembles a
parachute in both construction and appearance. This should not be confused with the
spinnaker chute which is a hull fitting sometimes used for launching and recovering the spinnaker.
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