Wharram's Mana's rig

Discussion in 'Multihulls' started by Aneblanc, Mar 30, 2016.

  1. Aneblanc
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    Aneblanc Junior Member

    Hello,

    I would be interested in your opinions/criticisms about the cat yawl rig of the new Wharram Mana but also present on other Wharram designs regarding windward ability and and ease of tacking compared to the classic Tiki rig.

    Thanks
     

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  2. RHP
    Joined: Nov 2005
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    RHP Senior Member

    For people's information Wharram describes the rig thus:

    MANA 24 uses the well-proven Wharram Wingsail rig in a new Catrig configuration, as developed on the AMATASI. The mainsail gives the drive with a very clean leading edge. The small mizzen aids with balance and steering. Having no jib, there is no need for a very tight forestay. The standing rigging on MANA 24 uses the latest concept, dyneema rope, which is light and easily set up. The mizzenmast can be used as sheer pole for single-handed mast raising.

    Length overall: 23' 6" 7.16 m
    Beam overall: 12' 8" 3.85 m
    Waterline length: 20' 10" 6.35 m
    Beam of each hull: 3' 2" 0.97 m
    Max. draft: 18.5" 0.47 m
    Dry weight (Approx): 990 lbs 540 kg
    Maximum displ: 2090 lbs 1140 kg
    Sail area: 216 sqft 19.6 sqm


    The Tiki 26 for comparison:

    Length Overall: 26' 7.92 m
    Beam Overall: 15' 1" 4.60 m
    Waterline length: 2'6" 6.84 m
    Draft: 1' 4" 0.40 m
    Weight: 1550 lbs 700 kg
    Loading capacity: 1700 lbs 770 kg
    Sail area: 285 sqft 26.5 sqm

    The mizzen looks too small to provide any drive so you'd be dependent on the main....
     
  3. Aneblanc
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    Aneblanc Junior Member

    Thank you for your precisions but they are not necessary for people who know the rig and from whom I am hoping to get answers regarding the windward and the tacking abilities.
    Cheers
     
  4. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    For starters it is a cat ketch (mizen ahead of rudder) and it looks to me like it's primary value over the standard sloop is that it allows balanced trim with air on a boat that has very limited foils in the water. This is a boat for long passages where you can choose downwind routs, arrive on remote islands and beach the boat high and dry at low tide. The sails are good aerodynamically -good platform, smooth profile. The biggest aerodynamic weakness is not the sail plan, it's the boat -wide, lumpy, sharp edges. This is not an upwind boat and it's not the soul fault of the sail plan.
     
  5. Aneblanc
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    Aneblanc Junior Member

    I know that it is a cat ketch but considering the respective areas of the 2 sails I took the liberty to call it a cat yawl. But this is not the point of the post.

    The point is, whatever the windward ability of the Wharram designs, comparing this rig with a classic Tiki sloop rig. Consider that the Tiki has in principle the same kind of hull.

    Cheers
     
  6. RHP
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    RHP Senior Member

    You sure know how to endear yourself.......
     
  7. Richard Woods
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    Richard Woods Woods Designs

    All the Tikis I have seen need to back their jib to tack. Most other catamarans don't need to. In fact if you have a screecher hoisted it is normal to roll it up when tacking and unroll it when on the new tack. Its faster to do that than pull it round the forestay

    I have sailed on yawl rigged small boats (eg Caledonia yawl) and the setting of the mizzen is critical for helm balance and even trickier when tacking in any waves.

    Most designers fit the mast near the centre of the boat to help reduce pitching

    I never like a boomless sail as it is so dangerous (flailing mainsheet block) when reefing. In fact most Tiki sailors lower the sail completely to reef and then rehoist

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
  8. Barra
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    Barra Junior Member

    Richard, if you find a boomless sail dangerous to reef, then the system isn't set up correctly.

    Mine is fully battened 12M luff with old fashioned Ronstan sliders.

    I love mine. Its so much safer and quicker to reef, than a boomed slab reef set up.

    Having chalked up around 40,000NM with mine, (actually on my 3rd sail now) , any flogging can be controlled with a lazy sheet (clipped on before transferring mainsheet) . Being fully battened the sail doesn't flog unless one has applied luff tension, or its pretty windy (3rd reef territory).then the lazy sheet does its thing.

    To Reef:

    1/ release halyard to pre marked location.

    2/ If necessary, (rarely) whilst the mainsheet still controlls the leach even though it is now pretty loose, hook on a lazy sheet into new clew point and tension.Very little tension required, i use 4:1 handy billy).

    3/ Transfer main sheet hook and sheet on.

    Main now reefed and sailing.

    At ones leisure ,tension luff downhaul ( most of ones work is done by the main sheet ) and tie in reef points.
     

  9. Richard Woods
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    Richard Woods Woods Designs

    But the Tikis don't have any battens, never mind full length ones! (and yes i have sailed with fully battened boomless mainsails)

    RW
     
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