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Old 05-23-2012
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Re: Overlapping versus Blade headsails which is quicker ?

When you are talking about modern boats, they are typically fractionally rigged and designed with very large SA/D's with the intent that they will not be sailed with overlapping headsails. The thinking is that this sail plan is more efficient that way and much easier to handle. These rigs are much easier to power up and down (not the same as reefing) and compared with older designs these new boats have a huge amount of stability as relative to thier drag and so can carry this large SA/D in a very wide wind range.

If there is a short coming to this rig proportion, it is at very deep reaching angles and dead runs in light to moderate wind, where nothing beats raw sail area. In racing, this is completely offset by the use of assymetric deep reaching spinnakers and to a lesser extent, code zeros. Cruising with these boats, you almost never head dead downwind in light to moderate conditions and so can usually get by with reaching at hotter reaching angles and building your own apparent wind when it does not make sense to fly a chute.

The problem with the Hanses is that they are surprisingly high drag for a modern design, and do not have all that much standing sail area. They are also limited by their next to useless self-tacking set up which means that the normal jib is very small (90% or so), and does not set as well as might be ideal. It sounds like you have a custom set up which may let you use a 105-109% headsail.

The hot ticket if you are having a custom 'all-purpose' made is to have it made from lighter weight, high modulus- low stretch material, cut slightly full for slightly higher headstay sag, and with a lot of roach and furlable battens. The key is to have the sail maker take physical measurements on ypur boat to maximize the luff, roach and foot length. The design should assume that the jib car is placed as far aft as possible but not so far aft that sheet hits the shroud when power reaching.

If done properly this results in a sail with excellent performance across an extremely wide wind range. The light fabric, larger area of the roach, and fuller shape works well at the light end of the range. As the breeze picks up, the backtstay adjuster can be used to remove headstay sag and flatten the sail. The low stretch fabric allows the sail to be carried well into heavier conditions, increasing backstay tension to further flatten the sails and then reefing at the top of the wind range.

I had Quantum build a sail like that for my boat and it has a range from 3 knots well up into the mid to high 20 knot range. Its 3 years old and basically looks like new.
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Last edited by Jeff_H; 05-23-2012 at 11:50 AM.
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