Clew Board Meaning in Sailing

A clew board consists of a rigid reinforcement plate located at the rear corner of a sail. This flat piece of metal or plastic spreads the high tension across the fabric. It provides a strong attachment point for the lines that pull the sail toward the rear. Without this plate the corner of the sail would easily tear under heavy wind pressure. Most modern racing sails feature these boards to maintain a perfect aerodynamic shape during travel. One example occurs when a sailor clips a heavy rope to the metal board on a mainsail. This allows the crew to pull the sail flat for better speed in a breeze. The board often features multiple holes for adjusting the height and the angle of the pull. Using this hardware increases the lifespan of the sail by protecting the delicate fabric fibers. This structural component is essential for the high performance of every modern and efficient sailing rig.