Small trimarans under 20'

Discussion in 'Multihulls' started by Doug Lord, Jun 24, 2012.

  1. Doug Lord
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    Doug Lord Flight Ready

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    I know all about Monkey-what does that have to do with anything I've suggested? It doesn't use the advanced foil system I've suggested.
    I only sailed a few hours last year. But I have thousands of hours sailing and racing,designing and building boats since I was 9 years old.(57 years)
    Again, what does the Monkey have to do with anything?
     
  2. waynemarlow
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    waynemarlow Senior Member

    Probably more in relation to this thread than the GC32
     
  3. Doug Lord
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    Doug Lord Flight Ready

    ---------------------------------
    Comparing the wand system on a foiling Moth to the wand system I have suggested for a trimaran is ridiculous. Completely invalid comparison. Pitch coupling with Moth wands is notorious. I've often criticized the Moth wand system because it is located way forward on the bow -therefore it responds to pitching as well as but not necessarily including altitude changes. If the boat pitches up or sails in short steep waves the wand is bound to come "loose" resulting in a crash. My wand system does not respond separately to pitching -only to altitude changes. Same was true of Dr. Bradfields wand systems on the Rave, Osprey and Skat-they are mounted midships like mine and they never come "loose".
    It's all a matter of design-Bradfield pioneered wand systems that worked-inshore or in the ocean-and their position on the boat wasn't accidental.

    Pictures-1) shows Moth with ward wand subject to pitch coupling and coming "loose" if boat pitches up or in short, steep chop. 2) Midship wand-no pitch coupling, no coming "loose"- picture shows windward wand, of dual wand system, that is never immersed. Wake of lee wand visible behind main foil:
     

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  4. Doug Lord
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    Doug Lord Flight Ready

    ================
    Again, I mentioned the GC32- after you dissed Martin Fishers A Cat work- to illustrate one of his greatest successes.
     
  5. 2far2drive
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    2far2drive Senior Member

    He always fails to say or acknowledge this part. He's not much of a "variable" type of guy, especially that very large variable.

    Ohh dont forget, they are all foil assist. not full flying. :D
     
  6. Richard Woods
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    Richard Woods Woods Designs

    So Doug, when you say "wand" or "foil" you actually mean "my wand", "my foils" rather than making comments about foils in general. Maybe in future you could make sure you say they are your ideas when you talk about foils. Maybe call them "DL foil" or "DL wand" so we know what you are talking about.

    And if your system is the only safe, easy one, then you really do sail your model more. Maybe get a trailer or inflatable roof rack so you can get the boat to the beach without help. Or use a headcam camera as I believe Ian from Perth does, so you don't need a cameraman

    RW
     
  7. Doug Lord
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    Doug Lord Flight Ready

    ---------------------------------
    That's not true, Richard. BUT when you or anybody else uses an example comparing the Moth wand system to my or Dr. Sams multihull wand systems I'll speak up.
    Give me a break, Richard!
     
  8. waynemarlow
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    waynemarlow Senior Member

    Wand or no wand, DL Wand or Moth Wand, at the moment the only wand systems that seem to be working in numbers are the moths and these have evolved into a fast but difficult little boat to sail well. The Whisper system seems to be working well. But each of these two boats are totally reliant on having very low weight combined with state of the art foils which rely on constant maintainence of the foil surfaces.

    In a racing / cruising Tri of 20ft, neither of those attributes are going to be feasible and practical, so where does that leave any practical further development, I would suggest rigs and a lessor degree, hull forms.
     
  9. Doug Lord
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    Doug Lord Flight Ready

    Sorry, Wayne but trying to say that the only wand systems that matter are on the Moth and Whisper is just completely wrong and poorly informed. Bradfields systems have been around for 20 years or more and are proven well designed systems and are MUCH less expensive to build than Moth* systems. Their application to a cruiser/racer tri(sport trimaran) is a perfect marriage of technology that has incredible benefits like flying the main hull in light air, flying the main hull above waves, controlling the angle of heel, automatic gust response and, with the rudder T-foil, allowing much greater pitch authority than on a "normal" same old same old tri.
    These advantages allow tri's with square and/or over square beam to be practical. Further, using a wand controlled main foil allows the technology to be extended down to very small tris.
    * The new foils being developed by the premier Moth builder for a new one design foiler called Waszp are 20% of the cost of the Mach II foils. And foils do NOT require constant maintenance.
     
  10. rcnesneg
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    rcnesneg Senior Member

    So why don't moths use them if they have been around that long?
     
  11. Doug Lord
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    Doug Lord Flight Ready

    The thing that is so cool about this era is that proven foil systems are almost everywhere. And, in designing a small sport trimaran, adding an advanced foil system to the main hull and amas is simpler than ever because there are 100% proven systems available from a design standpoint. Combining a wand controlled foil on the daggerboard with a rudder T-foil and "C" or UptiP foils on the ama is a natural using proven designs that any well qualified designer can use.
    There will be more experienced designer/builders that realize how good these combinations can be and more small tris built using them as time goes by. These are not experimental, unproven systems-they are well proven offering tremendous advantages to small trimaran design.
    The combinations of foil systems are new but based on well proven technology with significant sailing, comfort and handling advantages.
     
  12. Doug Lord
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    Doug Lord Flight Ready

    ===============
    Why don't Moths use what? The Moth wand system started out as a copy of the Bradfield system with the wand moved forward so that only a single wand would be needed. There is still a slight difference in altitude in some Moths from tack/gybe to tack/gybe because the wand is on one side of the bow. The pitch coupling and wands coming "loose" are disadvantages of a system that works well in a great majority of conditions.
    The Bradfield system doesn't have these disadvantages because the wand contacts the water close to the position of the F&A CG of the boat. And the Bradfield system on some cats or tris allows the wand(s) to be retracted when the daggerboard is pulled up-something not possible on a Moth. Most Moth builders consider the Bradfield system impractical because it would require two wands-one on each side though that arrangement has been used on a few Moths and on the giant monofoiler Mirabaud. The new one design Waszp Moth will have retractable foils and possibly a way to retract the wand as well.
    In my opinion, there is no better system than versions of the Bradfield system with particular attention paid to the fore and aft position of the wands. The new Whisper foiler uses wands that touch the water just aft of the daggerboards.
     
  13. Richard Woods
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    Richard Woods Woods Designs

    I am sure you do, but others may not. "you" is a plural as well as a singular word

    RW
     
  14. Doug Lord
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    Doug Lord Flight Ready

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  15. Skyak
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    Skyak Senior Member

    I saw lots of crashing in a high wind race at the Moth worlds and was wondering if anyone did any 'suspension' adjustment. Some adjustable damping should do the trick on choppy days. Judging by the repeated crashes they had a low frequency resonance they could not get though. A damper could raise that.
     
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