ADJUSTING SAIL SHAPE


Sails are not flat. They have curvature (called draft) built into them. The amount and position of this draft can be adjusted to match the wind speed. In light winds, you want a full sail shape and in stronger winds a flatter shape. This will keep the boat under control and sailing well. Any surplus energy does not contribute to boat speed but only increases heel and makes steering more difficult.


The Cunningham adjusts mailsail luff tension. As wind speed increases and the sailcloth stretches, the position of the draft moves aft in the mainsail. Tightening the Cunningham moves the draft forward, back to its proper position.


Tightening the outhaul depowers the mainsail by flattening the lower (and largest) portion of the mainsail.


Power-up for Light Wind A fuller sail shape adds power.


Increased Draft


Depower for Stronger Winds A flatter sail shape reduces power.


Reduced Draft


Ease the outhaul


Ease the Cunningham 73 Table of Contents


Tighten the outhaul


Tighten the Cunningham


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