Offshore Foiling Revolution-Gitana

Discussion in 'Multihulls' started by Doug Lord, Apr 16, 2015.

  1. coralislander
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    coralislander coralislander

    did not sail well in light air. Why was that?

    The drag caused by the foils not being retractable


    Not recorded as a record by WSSRC.

    http://www.sailspeedrecords.com/500-metre
     
  2. Doug Lord
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    Doug Lord Flight Ready

    Speed Record-Longshot

    You didn't look very carefully-look under "A" class at the link you posted....
     
  3. P Flados
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    P Flados Senior Member

    The trifoiler light air performance was very poor given:
    • The horizontal portion of the ama foils would be at or near stall due to very high AOA at low speed.
    • The rig was designed for low center of effort. Short rigs are much less efficient in the light.
     
  4. coralislander
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    coralislander coralislander

    Offshore Foiling Multihulls

    Sorry about that. Thought A class was A classification for Catamarans and shot to the top classifications.

    Doug.

    The L foils look like they are hinged and could be lifted and lowered by the helmsman with the ali tiller rod as the lateral resistance to hold them whilst foiling, lifting them when not foiling.
    I wonder what the force was at the achieved record speed @ 43.55 for them to remain foiling engaged.

    Interesting the same boat speed record for A class women is 17.81.
     
  5. Doug Lord
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    Doug Lord Flight Ready

    trifoiler

    Probably had some kind of lock to keep them in position.
     
  6. coralislander
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    coralislander coralislander

    Thanks.
    .[​IMG]


    Foiling on both L foils at the same time.



    Trying to foil but not enough wind. Can see the drag.


    [​IMG]
     
  7. Doug Lord
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    Doug Lord Flight Ready

    These type of "L" foils are always used together,at the same time.
     
  8. coralislander
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    coralislander coralislander

    Here is an item re DSS for bulb fully foiling cruising keel boats. At proto stage but I guess he is prospecting for more clients to expand the technology and obtain the necessary data for them to [ The designer Company for patented DSS ] to have versatility and a wider range vessel appeal.

    States very simplistic and not complicated and infers that any yachts person unfit with a middle age spread could foil with 4 hrs. approx. experience at the helm

    http://www.mysailing.com.au/news/dynamic-stability-systems-unveils-a-fully-foiling-keelboat?utm_medium=email&utm_campaign=Enews+June+15+2015&utm_content=Enews+June+15+2015+CID_32ceb6ac9350d32caf0245e72dd93126&utm_source=Email%20marketing%20software&utm_term=Dynamic%20Stability%20Systems%20unveils%20a%20fully%20foiling%20keelboat
     
  9. Doug Lord
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    Doug Lord Flight Ready

    Quant 23

    Coralislander, I don't know where you came up with "4 hours" but Welbourn says:
    "While the Quant23 is a foiler (albeit with a fixed keel), Welbourn is at pains to point out that she is otherwise fundamentally different to a Moth or an AC72. While those are grand prix racers, demanding athleticism, great skill and technique to sail, the new boat does not: “The idea is simply a boat that anyone can leap into and ten minutes later they’re flying.” "
     
  10. coralislander
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    coralislander coralislander

    Doug. Do you really believe that?

    I stated 4 hrs as I believe a person that has not been on a sailing yacht can safely or for a considerable period sail a sailing vessel to windward or any direction for that matter and they reckon all that can be achieved after 10mins a complete novice takes the helm and be foiling.

    Perhaps they mean as a passenger.

    How long do you reckon then Doug?
     
  11. Doug Lord
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    Doug Lord Flight Ready

    I personally know Hugh Welbourn and if he says 10 minutes its 10 minutes.
    The boat was designed specifically to be easy to sail and I bet it is. It's also designed to foil early rather than for top end speed.
     
  12. Doug Lord
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    Doug Lord Flight Ready

    Gitana

    Here's a video from MA showing her flying 100% a good portion of the time. The UptiP foil on the port ama was not down all the way. Just a few adjustments.....
    A daggerboard foil would ,at least, keep the main hull up all the time.

    https://www.youtube.com/watch?v=ce060M-XniQ
     
  13. Gary Baigent
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    Gary Baigent Senior Member

    Those know nothings at Gitana? - wonder why those incompetents didn't put a foil on the main dagger, a la Doug?
    Just look how Doug's model flies so smoothly and steadily and with great longevity and with great speed and with minimal drag with its multiple collection of foils.
     
  14. Doug Lord
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    Doug Lord Flight Ready

    Thanks, Gary! She did do pretty well on her very first time on foils-and was the first trimaran of any size to use UptiP foils on the ama:

    [​IMG]
     

  15. rcnesneg
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    rcnesneg Senior Member

    Goodness gracious! I never thought I would ever see a mod 70 foiling... What are they going to do next? Make a J-class foil?
     
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