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Dan Dickison
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Can you please explain the classification of sails such as a 110-percent genoa vs. a 115-percent genoa? And what's the percentage figure about?

Dan Dickison responds:
Thanks for your question. If you've been around the sport for any length of time you've no doubt noticed that it has a lexicon all its own. Without knowing the confusion that they cause, veteran sailors tend to throw around arcane terms like a chef at Benihanas does food. But the meanings usually aren't that obscure, so don't let these folks or their terms intimidate you.

The terms you've been hearing in regard to headsails (150 percent, etc.) refer to the size of that particular sail as it relates to the boat's foretriangle measurements. Say you've got a 150 percent headsail (or a 130 percent, etc.), that figure designates the LP or luff perpendicular measurement as a percentage of the "J" dimension. The LP is measured from the clew of the sail to the closest point on the luff of the sail. If the sail is a 100-percent jib, then the LP dimension is equal to the J dimension. A 130 percent headsail has an LP dimension of 1.3 times that of the J measurement. The J measurement is the distance from the base of the mast forward to the base of the headstay.

Now if you're asking, OK, what's a foretriangle, let me back up a bit. The foretriangle of the boat is the measured area that falls within the borders of the boat's foredeck, its mast, and its forestay. Now, if you don't know those last three terms, then my advice is to look them up. If you need to do that, SailNet has an on line sailing dictionary that can assist you. Here's a direct link to it: Sailing Dictionary. Here's hoping that this information is helpful to you.

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