Sail Area of new boats?

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J

Justin Wolfe

This has been bugging me, and recent comments about new Hunters sailing better than Legends made me look again. If you look at the sail areas listed for new boats on this site it would appear that the sail area is much greater on new boats than the similar sized Legend boats. AND in general the boats are lighter. Sounds really good... The problem I have is that traditionally sail area on spec sheets has been just the sail area of the triangles formed by I,J,P&E. The Legend boats and the rest of the world do this, but the new Hunters, sans backstay, do not. They use the actual sail area of the sails, which because of the roach, and the slight jib overlap gives a much higher (as in 100+ sq. ft) number. Does this make for a fair comparison? Granted the new numbers are actual, but now we aren't comparing apples to apples. Sure the Legends don't have all that roach, but they have some, AND they always have an overlapping jib. The overlap in the jib should be roughly equivalent to the extra roach in the new mainsail. To me this is deceitful. If not that, it sure makes it difficult to compare a new Hunter to the rest of the world. If you're interested in the numbers simply reading the specs doesn't give you a fair answer. Also, I mentioned that the new Hunters are generally lighter than the Legends. Sounds good, except in almost every case a significant amount of the weight savings is in the BALLAST. What's the deal? Take the 320 for example, compare it to a Catalina 320, J32, and Beneteau First 33.7. I think you'll find the Hunter is about 1500 lighter than the rest, but it has 1000 lbs (25% less ballast). Someone got it wrong and someone got it right here. That is a drastically different design philosophy. So which is it? Are Catalinas, J's, and Benny's overballasted (ie too stiff)? Or? Does Hunter know something the rest of the yacht design world doesn't know?
 
B

Been there

Sail area matters only to extent

That the boat has the stability to stand up to its canvass, without presenting too much freeboard and beam to air and waves. The J/32 has a PHRF of 126, according to the J boats website, and is rated 114 on San Francisco bay. Compared to the Hunter 340, it is lighter while having the same ballast. It's waterline is 6" longer while its beam is 8" less. I don't have stats on freeboard, but it looks to me that the J/32's decks are lower and that its cabin trunk covers less of the boat. As a result, and even though the H340 has more sail area, the J/32 is faster. And I suspect it is easier to sail and more comfortable under way. But it doesn't have an aft cabin, so it will never sell as well.
 
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Justin Wolfe

37.5 vs. 376

Sure only to an extent, but if you compare otherwise very similar, same purpose boats like the 37.5 and 376 it would be nice to be able to compare the two boats with similar information. In this case sail area should make a difference in performance (the boats are otherwise similar). When you look at the specs. you find the 37.5 has 704 sq.ft of sail and the IJPE gives 703.75. When you look at the 376 it says 847 sq.ft!, but the IJPE gives only 683.6. That's a difference of 164 sq.ft!!! My point? If you include the sail are of the 135%? standard jib on the 37.5 you get 817 sq.ft. So instead of the 376 looking like it has a much higher SA/Disp ratio what you find is that The 376 has slightly more sail area, and slightly less ballast. Translation, these boats are going to perform very similar, the 376 probably better in light air, the 37.5 better in heavy air, but overall very close. Again, if you looked at the brochures you would not get that impression. To me Hunter is doing a disservice to buyers by using misleading information (ie not following spec conventions). It would appear that a 376 or 380 has much higher sail area/displacement ratio than "older" "crabcrushers", when in fact the difference is actually very slight when you compare apples to apples. P.S. I'm not shooting the messenger, Phil, as I imagine he's taken the numbers right off of Hunter brochures.
 
D

Don Alexander

11% overclaim in SA

I too found it hard to accept the sail areas quoted in the literature and, charged with the job of handicapping the UK fleet, I measured my own sails. The main by taking the length of each batten and, as they are equi-spaced it was a simple job to put the dimensions into a drawing program. Next the jib on the lawn. The total I get for the UK sails on my 376 is 784 sq ft so the 874 sq ft claimed in the leaflet is 11% higher than my measerements. The roach on the main accounts for an extra 27% area over P x E /2 whereas for a normal (IOR) sail it is only 10%. Nevertheless I feel that the sail area is appropriate for the ballast and beam and we reef at about 18 knots true windspeed. The beam and powerful stern allow the extra area to be carried. Also she is very good in light winds. Indeed there are plenty of motorsailers which do not come on song until the windspeed approaches limits where I would rather be at home. As suggested the B & R rigged boats are a little faster overall. Any 376 owner wanting my details can mail me on donalex@compuserve.com Regards.
 
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Bryan

Keel weight and capsize screen

I'd probably want that extra 1000 pounds in the keel if I was in a big storm where there was a danger of getting rolled. Your observation, Justin, of keel weight made me curious. Look at the spec and performance ratios of the midsized (30-35) boats list here in the HOW. In the specs area, one notices a trend of lighter and lighter keels. Then look at the capsize screen ratios in the performance ratios. A general trend towards higher ratios. Goes from around 2 in the 80s to 2.10 for the more modern boats. I'm not an expert in this stuff, but from what I've read a ratio over 2 indicates a boat more likely to capsize and less likely to right itself. Maybe I don't understand the ratio, but I'd be nervous about getting caught in a Gulf stream storm in a 340 with a 2.10 capsize ratio. Having all that extra canvas wouldn't help either if a sqall snuck up on you. Maybe the newer designs have other factors that make them more capsize proof than the capsize ratio suggests. I'd hate to think that Hunter was saving a few bucks on lead cost at the expense of making boats that are more at risk of turning and staying turtle.
 
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Geoff Kloster

It's your choice

Don't worry about what the manufacture says. The important sail area is the sail area you put up.
 
B

Been there

Not entirely your choice

With one stick, you can't raise more upwind sail than a full main and a large genoa, say, a 180. To do even that, you have to carry multiple headsails, and swap them as light air turns to a breeze and back. Cruisers like roller furled jibs, they don't like to swap headsails, and they don't like big genoas, so modern cruising designs are moving to a SA/D of 18, 19, or higher, measured as 100% triangles, not counting roach or overlap. Working sail is then good even for light air. It means putting a reef in the main earlier, but that is easier than taking one jib down and putting another up.
 
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