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Old 01-19-2010
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Narrow fins with bulbs tend to generate more leeway than wider fin sections; although they carry more ballast deeper which helps them stand up and carry more sail area. The trade off is efficient in moderate winds when the boat can use the ballast weight as righting moment; but in heavy air this type of keel does not track as well as a wider fin section. (canting keels are outside the scope of this discussion)

A smaller headsail that can be sheeted closer to the centerline of the boat; sheets run inside the shrouds is better for pointing ability than a large headsail; but at the cost of reduced area. It would depend on the boat and the windspeeds that you would expect to normally sail or race in to determine if a close sheeted smaller headsail is better than a larger headsail and lower pointing angle.

If you are looking for a boat that points high and sails fast to windward you might research the PHRF ratings for upwind performance; there might be some variation in the numbers from the 'base' rating. A lower PHRF equates to a faster hull.

Nowadays most racing hulls are optimized for downwind sailing (Spinnaker) with a hull form that will plane while sailing downwind (ULDB); while still providing adequate upwind performance (with plenty of railmeat). That's not to say the VMG upwind is poor; it just is not optimal.

When a boat sails upwind at it's hull speed the apparent wind angle does move forward. It's how well the sails can produce lift (and how easily the hull is driven) at that shallower wind angle that determines how well the boat points. Heavier wider beam boats with full keels will not point as well as a lighter, narrow beam hull with a fin keel and close sheeted low stretch sails. But; the heavier built boat may be more comfortable in rough conditions and more able to withstand heavy conditions without any failure of the hull.

Last edited by KeelHaulin; 01-19-2010 at 05:23 AM.
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