Moth on Foils: 35.9 knots(41.29 mph)

Discussion in 'Sailboats' started by Doug Lord, Apr 11, 2006.

  1. Doug Lord
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    Doug Lord Flight Ready

    ========================
    Guilty!
     
  2. Doug Lord
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    Doug Lord Flight Ready

    Moth on Foils!

    Excellent article on the Moth and Moth racing in the November/December 2009 Sailing World......
     
  3. Doug Lord
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    Doug Lord Flight Ready

    Moth on Foils! Seahorse Sailor of the Month

    From Scuttlebutt:

    "Seahorse Sailor Of The Month
    Last month's winner:

    Bora Gulari (USA)
    'All hail Borat! Now take a shower' - Joe Gibson; 'Here comes the Robbie Nash of sailing' - Chris Williams; 'Bora's da man!' - Geoff Ewenson; 'This man invented sailing, water, beer' - Duncan Owlsey; 'A great effort by a determined dude' - Trevor Baylis; 'We are enjoying watching you from Istanbul' - Sacit Ertug; 'Because... he's a good guy, he just broke 30kt, America needs some good news, did I mention he's a good guy!' - Cam McTavish. "
     
  4. Doug Lord
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    Doug Lord Flight Ready

    Moth on Foils: new Blog:partial Span foils

    Interesting experiments by "Dr. Lojz": http://drlojz.blogspot.com/2009/11/i-am-connected-to-nature-air-and-water.html

    Like everything else, partial span foils have advantages and disadvantages. On the model they allowed thin foils with no chance of flap lockup due to flex of the foil. The flap ends can be subject to their own tip vortex increasing drag-it's a trade off like everything in design.


    10 year old partial span flaps from aeroSKIFF/14 year old thin partial span foil from F3:
     

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  5. Doug Lord
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    Doug Lord Flight Ready

  6. Jon Howes
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    Jon Howes Insomniac- sleep? Wassat?

    Good video. Notice the persistance of the ventilation bubble after the surface has been breached. An observation similar to this led to the Tomahawk foil concept since it suggested that the pumping losses due to maintenance of the ventilation cavity may not be quite as energy hungry as I had first anticipated.

    Jon
     
  7. Doug Lord
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    Doug Lord Flight Ready

    Moth on Foils! video

    More video from youtube-shot by fmg:

    http://www.youtube.com/watch?v=jr-b3ZIC_Uo


    From youtube,shot by Gulari:

    http://www.youtube.com/watch?v=CHWLk6JQ-DE

    Paper on low RE# airfoils: http://www.ace.gatech.edu/experiments2/6514/airfoils/fall02/borer_math6514_final_report.pdf

    Interesting foilkayak video-initially used John Ilett(Moth) foils: http://www.youtube.com/watch?v=uO54ZvDwt18


    Very interesting thread on SA-particularly post 89 on: http://forums.sailinganarchy.com/index.php?showtopic=98777&st=75

    Gulari: " i like black and white. "
     
  8. ancient kayaker
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    ancient kayaker aka Terry Haines

    Did Dr. Lotz mean the temperature of 15 deg C was too hot or too cold for sailing?

    I would have thought winglets would have been a simpler and more efficient method of reducing wingtip vortices than changing the tip profile. Also, I have only seen winglets on foils once and they were pointing up: is there a reason for that? I always assumed the reason they point up on aircraft was to clear the ground for tackoff and landing; I suspect they would be at leaast as efficient pointing down on a hydrofoil and they would then keep the vortices further from the surface.
     
  9. Doug Lord
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    Doug Lord Flight Ready

    Moth on Foils!

    This appears to be a really good idea for flaps that are not full span-from Primoz blog with his permission:
     

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  10. ancient kayaker
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    ancient kayaker aka Terry Haines

    Would a full-width flap achieve the same result?
     
  11. Doug Lord
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    Doug Lord Flight Ready

    I think it would and most Moth foils have full width flaps. That tip is shaped in a way that might make it hard to extend the flap full width-I think that was the point of the flexible part.

    Maybe Primoz will explain his theory....
     
  12. Doug Lord
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    Doug Lord Flight Ready

  13. Doug Lord
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    Doug Lord Flight Ready

    Gulari shortlisted by US SAILING: "Yachtsman of the Year"

    Nominees shortlisted for US SAILING's 2009 Rolex Yachtsman of the Year award: Lightning World Champion Matt Fisher (Columbus, Ohio); CST Composites International Moth World Champion Bora Gulari (Detroit, Mich.); Sheehy Lexus of Annapolis Melges 24 World Champion Chris Larson (Annapolis, Md.); Sunfish World Champion David Loring (Charleston, S.C.); SAP 505 World Champion Mike Martin (Newport Beach, Calif.); Finn Gold Cup Silver Medalist Zach Railey (Clearwater, Fla.); Rolex Farr 40 World Champion Jim Richardson (Boston, Mass./Newport, R.I.); 2.4 mR World Champion John Ruf (Pewaukee, Wisc.); DN Iceboat World Champion Matt Struble (San Diego, Calif./Bay City, Mich.); and Star World Champion George Szabo (San Diego, Calif.).
     
  14. Doug Lord
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    Doug Lord Flight Ready


  15. Munter
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    Munter Amateur

    Doug. Does anything in that video make you think you need to recalibrate your perception of how hard it is to sail a foiler?
     
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