Short Peak HalyardPrimer   Posted By: George Haycraft PC#29 here are two wrinkles, the  too tight wrinkle (peak to tack) , and the  too loose wrinkle (throat to clew) . Neither  wrinkle means you're in the ball park with the peak halyard tension. Within the no wrinkle range of peak halyard  tension, which may only be a few inches, you have considerable control over the sail shape. In light air, tension the peak  until you see the too tight wrinkle, and back off until it just vanishes. That puts you on the "tight" side of the no wrinkle  range, and results in a fuller draft shifted forward, which is powerful for light air. In heavy air, loosen the peak until you  see the too loose wrinkle. Then tighten until it just disappears. This leaves you on the "loose" side of the no wrinkle range.  T  The sail is flatter, the draft is further aft, and the sail is less powerful, but faster, like fourth gear.  Too loose wrinkle  18