Notable open & development class racers....

[Paul B]

Originally Posted by Vega

About the boat, look at this detail on the bow. For having more lift for planning easily in weak winds?

No, that's the way many boats with very fine bows are built. The flat is a mounting point for a filler piece that will complete the shape into a normal looking bow.

This gives a bow knuckle that does not cause great structural damage if it contacts something at speed. A sort of crash box.

[Vega]

Thanks! That bow really looked strange

[Vega]

Originally Posted by Stephen Ditmore

What's "Class America"? Is that what they're calling the IACC now? How is that relevant to the comments of any of the people you quoted, Vega?

Sorry but I don't understand what you mean. I have said that it was not relevant, only interesting, and as I was translating an interview, I thought there would be any members interested in what Juan and Farr think about the actual America’s cup boats, and what they think they should be like, in the future.

They call Class America to the actual boats that race the America's Cup.

And the relevant part to the quotes is the blue part. About the Class America talk (the red part) I have said:

Originally Posted by Vega

All right, this has nothing to do with the above, but it’s very interesting:


Do you prefer to work with Class boats or Open boats?

Open boats. We are very happy, doing Open Boats (3). That’s much more exiting than Class America, an uninteresting and completely obsolete class. The boats have a monstrous ratio costs/performance.

In what direction would you like to see an evolution of the Class America?

That’s funny because that question was also made to Bruce Farr and our answer is very close: A little bit more of 600m2 of sail area, around 90/100 ft length, canting keels…and more liberty on the class rules (regarding design).

The problem is that Chris Dickson (BMW/Oracle) is very conservative. He likes heavy boats. I don’t expect big changes.

Edited: But as you can see, they are not the only ones that call them the
Class America. From the official America's cup site:

"The class of boat used for the 32nd America’s Cup is the America’s Cup Class "

http://www.americascup.com/en/acclop...ers/weapon.php

[SuperPiper]

Here is a photo of Derek Hatfield's finished bow:

[Stephen Ditmore]

Sorry if I got on your case, Vega. I was just back from a business trip, without enough sleep & under pressure to produce.

There's a feature of the rules governing some of the open monohull classes that I see as distorting in favor of wide beams. That's the rule limiting heeling moment induced by movable ballast based on righting moment at 10 degrees. If HM(movable) were based on RM(90) instead of RM(10) it would be a more even race between wide and narrow boats.

[Vega]

That’s alright Stephen, but I still have the impression that you think that I am trying to prove that beamier boats are faster than narrow boats. I am not. I am only interested in the outcome and in learning.

Fact is that if you go to the thread about cruising costs and boats, you are going to see that one of my final choices for a personal cruising boat is a narrow and fast sailing boat.

What I have posted is not my opinion, but Juan’s opinion. In fact I don’t know enough to have a relevant opinion, but I know enough to have an educated look at the subject.

I hope you don’t mind if I go out a little bit of the subject of this thread, to pursue better this discussion, I mean narrow versus beamy boat in what concerns sailing speed.

In this month edition of a well-known French magazine, they have published a sail test between too fast French daysailing boats. Two interesting boats with interesting particularities: One of them is a beamy boat, the “Malango” the other a narrow boat, the Daydream, both designed by well known French NA, both with a curriculum in racing boats.

They have tested the boats on the same day, in conditions that went from 5 to 20k and they were really surprised with the test results. The boats were very close in all sailing positions and wind speed.

As the hulls were completely different, this means the boats didn’t “function” the same way, but somehow the results were the same.

The interesting part for me, will be to understand the way each of them functions to get speed. I believe that a lot of things can be extrapolated from this example to bigger boats with the same kind of hulls. I mean, typically the narrower boat has to have more ballast because it relies less in the hull stability and more in the ballast to have stability to carry its sails. Typically the Max RM is substantially bigger on the beamier boat and that means it can carry more sail, but it seems that the less drag of the narrow boat can compensate its inferior sail area and its slightly superior weight. Amazingly, these two very different boats end up having very similar performances.

Malango: LOA 8.7m; LWL 8.5m; Beam 3.45m; Draft 1.8m” D 2.8T; B 0.85T; SA 48m2
Max RM 3.256T/m

Daydream : LOA 9.5m; LWL 8.6m; Beam 2.7m; Draft 1.8m” D 2.9T; B 1.2T; SA 40m2 Max RM 2.0T/m

Speed test : wind 10k Close to wind: Malango 3.8K; Daydream 3.9K.
wind 10k wind on the back (Spy): Malango 5.3K; Daydream 5.3K.

Speed test : wind 20k Close to wind: Malango 5.7K; Daydream 5.7K.
wind 20k wind on the back (Spy): Malango 8.2K; Daydream 8.2K.
What do you think of it?

http://www.idbmarine.com/gb/malango.php

http://www.daydream300.com/e14cadrepont.htm

Note: the site only have the 300, this test was with the 310, a MKII version.

Regards

edited- data corrected

[Kiteship]

Originally Posted by Vega

Edited: But as you can see, they are not the only ones that call them the
Class America. From the official America's cup site:

"The class of boat used for the 32nd America’s Cup is the America’s Cup Class "

http://www.americascup.com/en/acclop...ers/weapon.php

Um, fellas? "IACC" stands for "International Americas Cup Class."

You're both right.

Dave

[Stephen Ditmore]

If I'm reading your numbers correctly, Vega, the Daydream wins walking away in 20 knots wind. I'm a little surprised, actually.... it's greater length should help, but I'm surprised it helps by that much. Where I would expect the narrow beam to help is going to windward in waves.... but the result seems to hold downwind as well. How do you explain it?

I haven't seen anything from Graal in a while. I like what I see of the Daydream.

Dave:
Yes, IACC stands for International America's Cup Class. It may be that they're calling thamselves something else these days, because (I think I read somewhere) they had a dispute with the ISAF that resulted in their pulling out. Apparently there is a question whether they should be using "International" as part of the class name if they are not an ISAF member class.

ISAF member keelboat classes are listed at http://www.sailing.org/default.asp?I...Y3DhnfU8U3z5~7.
I would assume the ORC GP classes are also recognised by the ISAF:
http://www.orc.org/index.php?id=86.
I think Transpac 52, Volvo 70, Class 40, and Mini 6.5 must be either independent or creatures of specific national authorities, and I think this is now the case with the America's Cup Class (by whatever name).

It was the construction "Class America" that threw me. I just wanted to clatify whether Vega, and those he was quoting, were talking about the America's Cup class or something else.

[Vega]

Originally Posted by Stephen Ditmore

If I'm reading your numbers correctly, Vega, the Daydream wins walking away in 20 knots wind. I'm a little surprised, actually.... it's greater length should help, but I'm surprised it helps by that much.

The data was not right, and didn't correspond with what I was saying. Sorry about that. Please take a look again.

Regards

Check this out -very interesting:
Sailormade Yachting from Berlin, Germany, recently launched their latest project
Address:http://www.sailinganarchy.com/innerv...elvolution.htm Changed:7:37 PM on Wednesday, July 28, 2004

[Vega]

Yes, very interesting. And the system seems to be a smart one. More information on their website:

http://www.sailormade.com/en/Yachten/Melvolution.php

[Stephen Ditmore]

Originally Posted by Vega

As the hulls were completely different, this means the boats didn’t “function” the same way, but somehow the results were the same.

That is interesting, Vega. Thanks for posting it. Can I assume neither boat used movable ballast in the test (aside from crew sitting on the rail)? Was the Malango in the test the keel version?

[Vega]

No movable ballast and yes, the Malango was the keel version.

[Stephen Ditmore]

So how far are Class 40 and GP 42 boats from competing on an even basis? Has anyone seen VPP results (polars, etc) or any other information that would give a clue? What are the factors that might make one faster than the other?

[Vega]

It is unfair to compare a 40class boat with a 42GP. The 42GP is an all carbon boat that is bigger and yet lighter. A 42GP would cost several times the price of a 40class boat. Only the GB42 sails would cost a good fraction of the 40class boat. The 40class boat has a limited choice of sails material (inexpensive), and the hull can not be carbon.

To be comparable we would have to compare the 42GP with an Open 42, and that boat doesn't exist.

Even if we persist in the comparison, it would only make sense if we put a 42GP racing with only one crewman. The crew of nine sitting in the rail would make quite a difference.

About the 40class boats, I will probably manage to have a Polar, but the max speed of those boats has to do with their extraordinary seaworthiness in bad weather. They are faster under extreme circumstances.

One of them has reached 32,4k, with over 45K of wind and in the middle of what the skipper has described, “The biggest waves he had ever seen”.

The boat was the one that was caught by a 8m breaking wave in the "Route du Rhum" and had, as a result broken the boom (I would like to have a boat that could get with a 8m breaking wave, and resist capsizing ).

The boat, after being repaired, was returning from Azores. They got 80k of wind, and finally, when the wind was blowing steady at 45K, with stronger gusts, they had fun and sailed at more than 30K (GPS).

That speed in an Ocean 40ft boat that cost US $250 000, is really amazing.

The boat is one of the two François Lucas design (the ones made of wood and with chines) and the skipper was Nick Bubb.