question on sails
Hey Mark, the percentage values are relative to the size of your foretriangle. So a 100% would be the exact same square footage as your foretriangle. That measure is the distance from headstay foot to the mast(perpendicular to the mast) * the height of the mast, all divided by 2. To find the area of a jib or genoa, you have two triangles, the one above the LP(luff perpendicular), which is the line from the clew to the luff, perpendicular to the luff. Use the triangle area formula(1/2 base * height) to figure out these triangles, and add them together. It sounds tricky, but it isnt. This number is your total area. Divide it by the foretriangle area, and you will have some value around 1.10, or 1.35, or 1.50. Thats 110%, 135%, 150%... get it? Good luck. And choosing the right sail, depends on the prevailing conditions, what you are trying to to, and how you are trying to do it, and some voodoo, for good measure.