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Old 01-04-2013
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Re: Beating to windward

Quote:
Originally Posted by rlltrash View Post
Can some sailboats point higher than others? I have heard that the Olympic class Star and Flying Dutchman sailboats can point higher (sail closer to the wind) than most other sailboats. I have also heard that catboats and catamarans usually do not point very well to windward.

Are these statements true? If so, is a boat’s pointing ability, or lack thereof, significant? (Is it a matter of just a degree or two, or ten to fifteen degrees?) Does good pointing ability mean good speed to windward, or are some boats faster to windward than others with only average pointing ability?

Can someone explain this to me?

Richard
It can vary by the design: some boats that look like tubs point just fine. Others that should be witches to weather are not. But as a general rule....

1. Long, narrow boats with fine entries point better than short, fat ones with bluff bows.

2. Deep hulls point better than flat-sectioned ones.

3. Boats with thin, blade-like appendages generate more lift (resisting leeway) than boats with long-chord keel & rudder.

4. Boats with inboard sheeting (usually fractional rig) point higher than boats with overlapping genoas.

5. Sloops point higher than ketches or yawls; cat(boat) rigs should (theoretically) point higher than sloops, but in practice turbulence behind the mast and lack of a slot effect cancels the benefits.

6. Slow boats point higher than fast boats; going too slow may cause leeway, tho.

7. Stiff boats point higher than tender boats.

Still. It's a package deal, and appearances may deceive. There are long, slender hulls betrayed by poor appendages or inefficient sailplans that don't point like they oughta (see Albin Vega). There are flat-sectioned beamy hulls like the Open60 that point quite high indeed: they ride on their hard chine, have incredibly good sails, deep narrow foils & ballast carried low, and maybe even daggerboards to increase lift. Tho chances are they will sail lower most of the time, just for the extra speed. But they CAN point high at need.

IOR boats are famous for good windward ability, yet they have outboard-sheeting genoas & moderate appendages. Just the ideal balance of righting moment, hull shape, and boat speed. OTOH, multis should point very high indeed (extreme L/B, high initial stability, blade jibs, powerful full-battened mains, etc), yet many struggle to achieve 45 degrees true. That's mostly because they are so fast, traveling up to 2x wind speed; they shift the apparent wind angle right onto the nose, so they have to crack off to keep the sails drawing. Odds are they'll still whup you to the weather mark, even tacking thru 100 degrees.

Finally, a given boat may see its pointing angles vary by 15 degrees due to conditions & the size of its 'groove.' Take our SJ21. Never the most weatherly craft (bluff entry, flat sections, swept keel, short waterline), there is a narrow window (8-11kts true) where that boat will tack thru 80 degrees, if you get the heel angle just so. Less wind, the foils stall and (being a light boat) boat speed is too high a percentage of wind speed, pushing apparent too far forward. More wind, the boat begins making leeway, chop knocks the bows off, and you need to ease sheets to prevent excess heeling. Narrowest groove of any boat I've ever sailed on: outside that ideal windspeed range, we are happy to tack thru 100 degrees & expect substantial leeway.

Etchells is a monster for pointing. Star, as you say, if you have crew that can droop-hike for two hours. Your Meter boats, even though their keels generally suck.
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