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  #256  
Old 09-21-2007, 11:16 PM
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Guillermo Guillermo is offline
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From Scuttlebutt:
"Ross Weene of Rodger Martin Design in Newport, RI sent this photo, announcing their latest launching, a Class 40, which is the first to be designed and built in the US. The official commissioning party is on Saturday, Sept. 22 at 4:00 PM at Newport Shipyard."
http://www.sailingscuttlebutt.com/photos/07/0921/
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Notable open & development class racers....-class40-usa.jpg  
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  #257  
Old 11-05-2007, 10:31 AM
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Vega Vega is offline
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Quote:
Originally Posted by CT 249 View Post


Vega, the Opens performance was good but as I understand it, the return leg was downwind. Also there was little light air beating, which the Opens do not like. The first Pogo 40 here, owned by a former National champion, has been performing very badly, as do some of our Open 60s. I'm not saying Opens are bad boats, but just pointing out that they and IRC boats are very different and seem to perform in very different ways (as successful Open designers have said to me).
[/quote]

CT, I am very interested in the discussion about different shapes of hull and performance (real time). I say real time because it is the only way you can separate real performance to the one that is artificially obtained by producing a boat that can do greatly under a certain set of handicap rules. A boat can be a winner on handicap and a poor performer if compared in real performance similar size boats, but not favored by that set of rules.

You have a lot of information that can be useful for a fruitful discussion on this issue and the Fastenet Race can provide more.

We can compare up-wind and down-wind times (till the Fastnet rock; From the Fastnet to the Finish).

I am very interested in that information about “your own Open60s” and the absolute performance compared with other boats of the same size.

I am also very interested on Information about the performance of that Pogo too.

Of what boats are you talking about? I don’t know of any new generation Open60’s racing in Australia.

If they are old ones, they just can compare with the new ones.

Take a look at this interesting post by Brian Eiland:

Quote:
Originally Posted by brian eiland View Post
...courtesy of Tim Jeffery
.....
.... in the last two years, the explosion of interest, budgets and sophistication in the class has been cataclysmic.
...
As Owen points out, old boats which were seemingly ageless now look redundant beside the latest in the class such as Michel Desjoyeaux's Foncia or Mike Golding's Ecover, the latter designed by Owen and Allen Clarke.

You can see the rate of progress in deck and sail systems, hull shapes and a staggering diversity of mast styles, ranging from fully rotating wings supported by great struts projecting from the hull to ruggedised versions of the normal.
...
Golding, one of the race favourites, can plot the progress of the class. The first of his three Open 60s he had over the last 10 years is now Dee Caffari's Aviva. ....It's a huge increase in sail area, a huge increase in power and in terms of sophistication of the boat," Golding says. Whereas Aviva has just a couple of inside ballast tanks to trim the boat, Ecover has 10. "You have more gears basically," he adds.
Note that as I have said on another thread I like narrow boats and I like large transom boats. I like all sailboats that excel in sailing, no matter the shape. If I many times defend boats like the Open 60’s or the Class40 is because sometimes we had in this forum ridiculous affirmations about their seaworthiness or about their ability to go upwind and because the development of the Open60’s in the last couple of years had been fantastic.
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  #258  
Old 11-08-2007, 04:54 AM
CT 249 CT 249 is offline
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"CT, I am very interested in the discussion about different shapes of hull and performance (real time). I say real time because it is the only way you can separate real performance to the one that is artificially obtained by producing a boat that can do greatly under a certain set of handicap rules."

But not all handicaps are artificial. In fact, what can be truly artificial is the claim that the "fastest" boat (as we normally assess it) is the best or most efficient.

This is largely because we tend to normally use speed for overall length as the main way to assess boats outside of "artificial" rules. However, this encourages designs that cram massive rigs onto fairly short LOAs. This is often not efficient in terms of speed for cost, speed for sail area, speed for ease of handling, etc.

Look at dinghies for a classic example. An International 14 is a wonderful boat, with about 200 ft2 of sail upwind and 500 ft2 downwind. It goes about 20% faster around the average course than an NS14 which has 100 ft2 of sail, or a 14 foot Merlin with about 120 ft of sail upwind and some 200 downwind.

Which is more efficient? Yacht sailors fixate on the boats that are faster for their LOA, but dinghy sailors are aware that a boat that goes 85% as fast on 20% of the sail area is actually more efficient in most ways.

Adding sail area tends to be a game of diminishing returns. Rating rules can reduce this tendency. I would say that a boat with a simple fixed fin, simple rig, decent accomodation and maybe 20% less sail but goes 10% slower is more efficient than a boat with a huge rig, complex sails, lots of foils to have to work on, and no interior.

The cost increases in Ecover's sophistication, "huge rig" and 7 extra ballast tanks must be considerable. I'd like to see a rule that discouraged large amounts of money (as much as that is possible).

"I am very interested in that information about “your own Open60s” and the absolute performance compared with other boats of the same size."

My information is a few years old. A couple of designers of succesful Opens (like the top 50 footer in the around the world) said that their Opens were not as good around short courses as conventional boats.

At the same time, Mini transat sailors said that their 22s with huge rigs were no faster around short courses than simple "family" sportsboats like the Elliott 7 which were a fraction of the cost. Sure, the Opens were better in some condtions but the "normal" boats were better at times too.

"I am also very interested on Information about the performance of that Pogo too."

I've given up offshore racing - too many big boats. I don't race against it and only see its results (It's called Krakatoa, it sails from Sydney, it did Hamilton Island and the Southport race; results are on the net.)

"Of what boats are you talking about? I don’t know of any new generation Open60’s racing in Australia. If they are old ones, they just can compare with the new ones."

But nor can 7 year old "conventional" boats compare with new ones. A Farr 52 (leading edge then) is nothing like as quick as a TP 52 (leading edge now).

I defend conventional boats for the same reason you defend Opens - because you feel the record should be kept straight.
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  #259  
Old 05-21-2008, 10:49 AM
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Stephen Ditmore Stephen Ditmore is offline
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  #260  
Old 06-27-2008, 12:25 PM
xarax xarax is offline
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Quote:
Originally Posted by CT 249 View Post
"
...a game of diminishing returns.
If we could somehow rephrase the well known Law of diminishing returns ( also known as the Law of diminishing marginal utility) of economics in sailing terms, we might say something like that:
In a sailboat of a given size, increasing one basic dimension ( beam or canoe body draft or mast height or total sail area or ballast) beyond some point, yields less and less additional boat speed.
So, if we could not achieve a substantially higher boat speed by, say, 25%, at the end, why should we have increased its beam by a proportionally equivalent amount in the first place? The same can be said about the total boat cost, if we are interested in keeping this cost within reasonable limits.
We can envision a sailboat class rule that, starting from a base open “box” rule of a given boat size, allows certain modifications (increments of the basic box dimensions) if, and only if, they are worth the trouble, i.e. if it can be shown that the specific increase in boat speed they yield is roughly proportional, in a way, of the modification involved. The proportionality factor may be different for each element of the base box rule we modify. For example, we may be ready to allow a 25% increase in beam if we could came up at the end with a 5% boat speed increase, or a 10% increase in sail area if we could come up with a 7% increase in boat speed, etc. Something like that may be considered for the cost of the boat. If we allow the use of a rotating two element wing mast, will the added cost be proportional, in any sensible means, to the added boat speed?
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