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Old 11-08-2013
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Quote:
Originally Posted by EricKLYC View Post
How about this :



Best regards,

Eric
This time they seems to go faster but only with three guys as ballast with one I don't see it going fast. That project is a study for a a big boat. I don't get it. It has not the advantages of a monohull in what regards safety and I don't see any advantage over a multihull.

A monohull is much more forgiving to sail than a multihull because the RM that is utilized for sailing (at 30º) is not the max RM . Max RM on most monohulls is between 50 and 70º. That means if the boat catches a strong gust it will heel and not only the wind pressure will be less (sail heeled) as the RM of the boat will be considerably bigger than at 30º, putting again the boat on its feet.

This one is made to have max sail performance with Max RM. That is nice in what regards performance but what will happen in a gust? The boat will heel more and with more heel the boat will have a smaller RM. It can work on a dinghy where the guys can compensate that moving the body and acting quickly on the sails but what will happen on a a huge yacht, the original project?

Not a good idea on a bigger boat.


Interesting anyway but I think the project developed by Defline is more interesting in what regards bigger boats.

Also, I know the bow is supposed to be wave piercing but even without almost no waves and two guys trying to lift the bow it seems it tends to go underwater a lot. It seems to me that there is not enough fluctuation there.

Good time to review what I have said about this interesting project:

"This is indeed an interesting idea but it seems that it is not working out at least on the first boat. They don't seem to have enough RM. The conditions seem pretty soft, with not too much wind and they have to balance the boat with the weight of the body. Contrary to what I think Murnikov expected, when the keels comes out of water the boat seems to lose quickly stability.

I guess that it is because the keel work as a foil and creates stability even if it was not maximized for that, like on the DSS project.

Maybe we can combine both projects: Maximizing ballast effect maintaining it at the better angle to provide Max RM while profiling that keel to aerodynamically make a downward force. Maybe it is not much difficult to make a variable profile with small servo electric engines (like on an airplane).

That way it could be possible to maintain the keel always in the better position (slightly inside the water) adjusting the profile to give more or less downwind force according with wind intensity.

For working that way that bulb has to be modified, giving it a much more elongated form, diminishing drag. Like it is, it was made to be out of the water and now it would be inside the water all times.

It seems that they don't go that way and I don't like the way they are going. It seems to me that those wings on the new modified boat will be just to provide more RM trough the displacement of the weight of the crew. That would not work out on a bigger model.

In fact if they want to test for a bigger model the way they are doing it makes no sense. The RM provided by the weight of the crew will have in the smaller model a completely disproportionated effect providing much more RM than it would be possible on the bigger boat where the crew will weight proportionally a lot less regarding the total weight of the boat."


Quote:
Originally Posted by PCP View Post
For years I have been seeing designs from Vlad Murnikov about his vision of the fastest monohull, a boat that could be as faster as a multihull, a huge boat (100ft) with the looks of a space ship. Well the designs were nice but the guy is not a leading NA and I guess it was just some dreamer with interesting ideas:





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Then, some time a go I heard that Roger Martin (a leading American NA) was involved in hull and deck shaping, general layout and detail design, that Hugh Welbourn (the one from DSS technologie) was part of the team and that Computational Fluid Dynamics (CFD) and sails was been developed by Tyler Doyle from Doyle Sails while SP-High Modulus was taking care of the structural engeniere. I thought to myself, jesus this is for real now.

When I heard that Lyman Morse was making a small prototype with 27ft I got really excited about it. After all they are promising the fastest monohull ever built, a boat with:

Delta-shaped hull, almost triangular in plan view, with a very narrow, wave-piercing bow to reduce resistance and improve seaworthiness.

Maximum stability and sail carrying capacity due to the innovative Ultimate Canting Keel with a bulb that comes out of water to provide the highest possible Righting Moment while completely eliminating drag.

Telescoping keel that retracts to reduce draft while in harbor and extends while sailing to maximize Righting Moment.

Stabilizing foils to further improve stability and reduce drag by partially offsetting boat weight. Similar to the DSS foils pioneered by Hugh Welbourn, SpeedDream wings are used in combination with canting keel and, in addition to lift, provide lateral resistance.

The resulting stability is far superior to all current keel boats while requiring only fraction of the ballast, thereby significantly reducing the total boat displacement.

The innovative and practical deck layout and superstructure styling that keeps crew safe and deck free of excess water even at high speed.


Well, the prototype is on the water. The images are not spectacular and I start to have some doubts. I truly hope they will be soon posting more spectacular movies and that this one is just not showing the full boat potential.

To follow closely







Regards

Paulo
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Last edited by PCP; 11-08-2013 at 10:15 AM.
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