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  #1  
Old 02-12-2011
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Polars, PHRF, boat speed, boat shopping

Why don't more manufacturers, or even more accurately, why doesn't the general public demand more information on boat performance?

Since my current boat is rather slow, I've been shopping for a much faster boat. However determining speed performance has been nearly impossible. About the only rating common to most boats for comparison purposes has been PHRF, which seams to give some indication of performance but not much. SA/D doesn't seam to tell you much, as my current boat has a pretty good SA/D ratio, but is still pretty slow, even in light winds.

A comment made to me by the manufacturer's rep concerning the Hunter Edge was that anything under 20 feet with a keel will be slow, however from what little bit I have seen, the Edge seams like it would be slow as well, even though it is a pretty long boat. But its difficult to know for sure. Why can't one find polars, or even some indication in the boat reviews, some sort of indication like on a beam reach, with ~10 knots of wind, the boat was moving X knots. Then what angle at a close reach does the speed really start to fall off. But no one ever seams to want to publish that. Beneteau seems to be about the only company that publishes polars, which seems very useful for shopping.

Last question, can one sail a water ballasted boat with no ballast in light winds? In other words, if the wind is under 10mph, or maybe even 8 mph, can one just leave the ballast out, and make the boat perform much better, or even partial ballast? In theory, an adjustable ballast would be very desirable if it worked.

( I started looking at tirmorans, but they are all way out of my budget league)
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Sailing a large boat on a small lake is very tacky.

Last edited by Daveinet; 02-12-2011 at 09:11 AM.
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Old 02-12-2011
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Quote:
Originally Posted by Daveinet View Post
Why don't more manufacturers, or even more accurately, why doesn't the general public demand more information on boat performance?
Most people don't care all that much. If the opening shot in an advertisement is a boat's interior--common to Hunter's--performance isn't the selling point. Some class and owner's associations compile Polars.

Quote:
Originally Posted by Daveinet View Post
...Last question, can one sail a water ballasted boat with no ballast in light winds? In other words, if the wind is under 10mph, or maybe even 8 mph, can one just leave the ballast out, and make the boat perform much better, or even partial ballast? In theory, an adjustable ballast would be very desirable if it worked.
Yes
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Old 02-12-2011
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I haven't even found a boat that comes with a decent owners manual. I believe that boat manufacturers don't even know the basics, let alone all the customized commissioning that is commonly done.
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Old 02-12-2011
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Quote:
Originally Posted by Daveinet View Post
Why don't more manufacturers, or even more accurately, why doesn't the general public demand more information on boat performance?
...
You can ask and if they think you are really interested in the boat they should provide you with a boat polar and a stability curve. If they don't its because they don't want (the designer should have made both) and that is a bad sign, if you are interested in a fast boat.

What is the size of boat you are looking and your budget?

Regards

Paulo
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Old 02-12-2011
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What is the size of boat you are looking and your budget?

Regards

Paulo
Size limits are to what is trailer-able. Budget should be limited to around $10K used. In theory, I could go much higher on budget if the sailing concept was more palatable to the rest of the family. In other words, I could afford more, but for something that only I enjoy, it should not consume that high of a % of available funds. DW sort of got interested in the concept of a power sailor because she does not like to be so dependent on something so fickle as the wind. But if it is a dog under sail, what is the point? Anything moving less than ~4.5 knots gets pretty boring for the rest of the family. Trimoran could be perfect, but way beyond the budget unless I got real lucky. Boat needs to have at least a cabin where one can sit fully upright. (not that I was interested, but a Capri22 cabin is too short)

I had been previously interested in the smaller Beneteau's Firsts, but after seeing a larger First at a show, I was very unimpressed with the quality of the interior. Don't have enough experience about boats to judge the exterior and rigging, but if the interior construction was any indication, I was disappointed. Was made like a cheap RV.
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Sailing a large boat on a small lake is very tacky.
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Old 02-12-2011
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Size limits are to what is trailer-able. Budget should be limited to around $10K used. ...

...
The only one I know that comes close to that price (new) is the Varianta 18.

Varianta Segelyachten - from Dehler with love

It is made by Dehler, now Hanse group and is sold exclusively by internet.

It is a fast and amusing boat that has made a big success in Europe for its Price/Performance.

I don't know if Hanse is going to import it for the States.
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Old 02-12-2011
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It's a shame that you can't find a multihull in your price range. That seems to be the answer to all of your problems.
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Old 02-12-2011
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Quote:
Originally Posted by Daveinet View Post
Why don't more manufacturers, or even more accurately, why doesn't the general public demand more information on boat performance?
Most people don't care much about this as said previously, so the manufacturers generally don't have the numbers.

Quote:
Since my current boat is rather slow, I've been shopping for a much faster boat. However determining speed performance has been nearly impossible. About the only rating common to most boats for comparison purposes has been PHRF, which seams to give some indication of performance but not much. SA/D doesn't seam to tell you much, as my current boat has a pretty good SA/D ratio, but is still pretty slow, even in light winds.
SA/D is just one of many factors that goes into determining how fast a boat is. If two boats have the exact same SA/D but one is a longer, more modern design with a high-aspect bulb keel and high-aspect mast and sail plan, and the other is a shorter, full keel with gaff rig, the first is going to be a lot fast that the second because it will have a longer waterline, less underwater drag, and a more efficient sail plan.

Quote:
A comment made to me by the manufacturer's rep concerning the Hunter Edge was that anything under 20 feet with a keel will be slow, however from what little bit I have seen, the Edge seams like it would be slow as well, even though it is a pretty long boat. But its difficult to know for sure. Why can't one find polars, or even some indication in the boat reviews, some sort of indication like on a beam reach, with ~10 knots of wind, the boat was moving X knots. Then what angle at a close reach does the speed really start to fall off. But no one ever seams to want to publish that. Beneteau seems to be about the only company that publishes polars, which seems very useful for shopping.
Manufacturers often don't generate polars. Also, polars are a bit subjective. If you have a lousy sailor, the polars generated by the boat will be quite different that those by an excellent sailor. There are a lot of variables in how fast you can get a sailboat to move, beyond its design. The skill and quality of the captain and crew matter a lot, unlike on power boats. So does the maintenance of the hull cleanliness, etc.

Quote:
Last question, can one sail a water ballasted boat with no ballast in light winds? In other words, if the wind is under 10mph, or maybe even 8 mph, can one just leave the ballast out, and make the boat perform much better, or even partial ballast? In theory, an adjustable ballast would be very desirable if it worked.
No, you really don't want to do that. There are serious risks involved and there's also a good chance that your insurance won't cover you if you capsize the boat and damage it with empty or partially empty water ballast tanks.

Quote:
( I started looking at tirmorans, but they are all way out of my budget league)
Too bad, they're great boats, but my opinion might be a bit biased.
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  #9  
Old 02-13-2011
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Too bad, they're great boats, but my opinion might be a bit biased.
It may actually be your fault I started looking more seriously at them. Some post you made on another thread in contrast to a power sailor, suggesting a trimaran which if properly power would go just as fat as the power sailor or on a windy day, go that fast anyway. Just got me kind of thinking about my goals and the best way to achieve them. That and multi-hulls being familiar territory with the HobieCat. That may be some of the reason for the disappointment with my current boat.

Quote:
SA/D is just one of many factors that goes into determining how fast a boat is. If two boats have the exact same SA/D but one is a longer, more modern design with a high-aspect bulb keel and high-aspect mast and sail plan, and the other is a shorter, full keel with gaff rig, the first is going to be a lot fast that the second because it will have a longer waterline, less underwater drag, and a more efficient sail plan.
And that is the reason for the discussion, trying to really determine what to look for in a boat that you want to be fast. Even from you comments, I would not know the B235 was that much faster than the Hunter Edge.

I'm really amazed more people don't care more about speed. Its that effortless forward motion that makes sailing relaxing. If the boat always feels like its struggling to move, your brain struggles too. I remember the very first boat I ever road on as a kid. It was a large under powered cabin cruiser that struggled against the waves. I remember hating it, because the motor working hard, made me work hard. Later learned to sail on lightweight fast dingies and found it very relaxing as there was no effort. The boats just glide along. The cat does the same thing and just effortlessly glides along. My current boat just feels like I'm trying to sail a bowling ball. I've been on some larger boats that were nearly the same way, not as bad as my boat, but never got that gliding feeling either.
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Sailing a large boat on a small lake is very tacky.
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Old 02-13-2011
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"Why can't one find polars,"
BECAUSE THEY COST MONEY. You can in fact have any boat measured and have polars (a VPP profile) run on the boat, if you want to pay for it. And racers regularly DO pay for it.
But the pikers in the mass market only want to know that this boat costs $19,995 and can be financed for $299 a month, while that other boat costs, ooh, $20,495 and $319 a month, and that's way more money, way too much.
So they buy the cheaper boat and who cares about all those confusing NUMBERS on the POLARS?

That's reality in any mass market, Dave. Get used to it. You want facts, you want numbers, you don't want to buy what the nice man in the shiny suit is best for you? You're gonna have to spend money and do homework, because you're bucking The System and they won't stand for that.

You want a fast boat? That's easy to find. Go racing. Go hang on a committee boat and work with the RC, every one of them needs and welcomes help. See which boats are winning, see which boats have one design (OD) classes. See which boats are part of the "sail of the month club" where the owners buy new sails every month to keep their competitive edge. (Nice if you have the wallet for it.)

But don't expect the guys who are in the business strictly to make a profit, to make your life easy. They'd rather sell you the wrong boat four or five times than sell you just one. There's no money to be made in selling just one.
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