Small trimarans under 20'

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

  1. BlueBell
    Joined: May 2017
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    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Interesting, thanks Dolfman.
    What a shame he doesn't believe in diagrams instead of word-smithing.
    Hard reading for me.

    I sea-trialed angled, triangular sheets of 1/4" ply on a 2x2 beam (8' / 2.4 m ) across the deck of a SOF, sit-on-top vaka.
    2' (60cm) sided traingles.
    About 30 degrees off the horizon, front view, and ~9 degrees AoA.
    We could only make about 3 1/2 knots paddling kayak style so ended up lowering them much further into the water than I expected to achieve roll damping near zero.
    No stability in the vaka, vertical sides, 17' loa x 13" beam (vertical sides, 5" of freeboard).
    We rolled right over several times.

    Sorry, no pictures, just words.
    Can't manage to post them on this forum.
    Please don't tell me how easy it is, as it is impossible for me.
    I've wasted to much valuable time trying and refuse to waste another second on it.

    Cheers
     
  2. BlueBell
    Joined: May 2017
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    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Great video!
    Love the gimballed camera!
     
    Corley likes this.
  3. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Dibley/ Robinson 5000 tri --update: Back in 2015 ,Kevin Dibley said that foils would be considered down the line. Mods were done to the amas to allow the main hull to fly. I wrote to him today to check in on development so maybe more news later.....
    PS- great numbers on the final boat-definitely foiler material!!
    Robinson 5000 Trimaran, Sailing Boats by Dibley Marine http://www.dibleymarine.com/sail/sail/robinson_5000.html


    SPECIFICATIONS AND PRINCIPAL DIMENSIONS
    LOA 5.000 m 16’ - 5”
    LWL 4.890 m 16’ - 1/2”
    Beam (Sailing) 3.000 m 19’ - 10”
    Correction: Thanks to Doug Halsey in 2015, it appears the beam is only 3m, not 19'10".

    Beam (Trailering) 1.096 m 3' - 7"
    Displacement (Sailing) 155 kg 342 lbs
    Displacement (Lightship) 75 kg 165 lbs
    Sail Area 13.24 sq.m 142.5 sq.ft
    Disp/L Ratio 37
    SA/disp Ratio 46.6

    Dibley--robinson_16_sail_plan.jpg

    Dibley-robinson_16_plan.jpg

     
    Last edited: Aug 14, 2018
  4. Dolfiman
    Joined: Aug 2017
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    Location: France

    Dolfiman Senior Member

    I have got by chance this 2001 photo (attached) of Chris Evans Boomerang (Foiler21) equiped with triangular boards as amas, but no info available on how it works (?)
     

    Attached Files:

  5. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Those foils are the essence of Bruce Foils! Great picture.....
     
  6. OzFred
    Joined: Nov 2015
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    Location: Earth

    OzFred Senior Member

    In the same document there is the Exoplane-1, designed around 1968, that progressed to the Exoplane-5 in 1994. It seems to pre–date Sail Rocket's use of the same configuration by more than 30 years. It used a float-mounted, canted rig and "boards" (forerunners of modern curved lateral hydrofoils) for lateral stability but they also lifted the boat.

    Now that is impressive.

    Unfortunately materials weren't up to the stresses, imagine what they could have done with a bit of carbon fibre.
     

    Attached Files:

  7. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

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  8. Dolfiman
    Joined: Aug 2017
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    Location: France

    Dolfiman Senior Member

    Tricote, an example of the transformation of a standard monohull day-boat (a Lanaverre 590) into a tri with Hobie cat floats as amas. For family sailing purpose, with more speed (although far from a pure trimaran) and no heel. Boat features at the end of the video :
     
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  9. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Interesting ,but it seems the outboard side of the Hobie hulls should have been the flat side...
     
  10. Corley
    Joined: Oct 2009
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    Location: Melbourne, Australia

    Corley epoxy coated

  11. Lurch723
    Joined: Aug 2012
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    Location: Devon UK

    Lurch723 Junior Member

    That looks pretty quick and even sounds pretty quick to me
     
  12. Cholsson
    Joined: Aug 2015
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    Location: Gothenburg

    Cholsson Junior Member

    Just added some action from last race of the year in Sweden. The wind came really fast and I thought was going to swim.. but :)
     
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  13. BrianJ
    Joined: Oct 2018
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    Location: Redlands,( Bayside brisbane Qld. Aust.)

    BrianJ Junior Member

    I believe the early 'Hobie cats' were financial successes only, due to extensive marketing, (look at McD. and Coke not good products but very well marketed). What a bugger of a boat, flat decks forward, no forefoot to speak of, too much rocker,not enough bouyance foreward too much power for hullshape, (Tornado 10' beam with slightly more sail). No wonder Newick designed a centre hull, their far better as floats than cat hulls. That will open a can of worms I bet. Am I right?.
     
  14. Doug Halsey
    Joined: Feb 2007
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    Location: California, USA

    Doug Halsey Senior Member

    Unlike those other boats, Hobie cats were designed to play in the surf. And they were great at that.
     

  15. upchurchmr
    Joined: Feb 2011
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    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

    Designed to play in the surf - and they worked great.
    They were still very good boats, in the hands of someone competent.
    Surprisingly good in my opinion.
    They opened sailing up to a huge number of people - even first timers. Exciting.
    The Prindle was better in having more depth forward to "minimize" pitchpoling, but it never caught on in peoples imagination.
    The Tornado was still a lots better boat, but a PITA to setup for sail and trailer - so it had problems of its own. Especially including the cost.

    And Newick twice changed the amas for the Tremolino to be larger.
     
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