Aftmast rigs???

Discussion in 'Sailboats' started by jdardozzi, May 28, 2002.

  1. brian eiland
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    brian eiland Senior Member

    Thanks Pogo, very informative post.
     
  2. pogo
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    pogo ingenious dilletante

    Thanks.
    I'm sure you' ll discover more disadvantages/ advantages of the different systems when you figure them out.

    For me , so far, the set back Boom with track and double radiused traveller track is still the best solution for a non-overlapping ( triangular) headsail.

    So I've two questions.
    Can you please explain all advantages and disadvantages of the " Bierig" ?
    Might a slab-reefable Bierig ( two battens) with boom be the non- plus- ultra ?

    pogo
     
  3. brian eiland
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    brian eiland Senior Member

    Pogo I visited this other forum discussion on Chris White's MastFoil and rediscovered this posting of yours:
    I'm really going to have to seek out a copy of that book/paper,...or certainly a photo of that boat. Is there ANY other info around on that vessel??
     
  4. pogo
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    pogo ingenious dilletante

    As a digital disabled person, as an analog person , my possibilities are limited. :)
    I don't like computers , and i'm proud of it.
    Please send me your fax nr. via pn and i'll send you , with some help of my daughter , everything i have.
    Put the blame on me , i gonna bear it , i' m old --experienced enough.:p

    Perhaps it would be a better way trying to contact Klaus Schrodt directly ?
    I think he was several time aerobatic champion, all times being very interested in aerodynamics , for this reason he sailed multihulls.
    Prof. F. X. Worthmann , designer of this special rig , died about 1980--- no source.
    In fact , the Junkers Doppelflùgel was a very effective way to improve aircraft's low speed performance.
    Exactly what sailing crafts are encountered since ever and nowadays.
    Chris White has , in my opinion , found the right way. He has opened , after Worthmann in the seventies , that door again .
    Unfortunately there is nothing to find about Worthmann's work in the www. ---1970 !!!
    Perhaps one should contact White directly ? The Principle of the Junkers Doppelflügel is obvious. Surely he knows the Junkers Doppelflügel , surely he knows Wothmann's FX profiles, but is he aware about Worthmann's rig ?
    AirFoil TM does it with flaps on the wingmast , Worthmann did it with a tiny main behind the wingmast.
    Both solutions work well.
    But, they look weired , strange; for this reason they aren't and weren' t accepted. Yachtsmen are conservative.
    It' s up to us to change that. This kinda rig is very practical !





    pogo
     
  5. brian eiland
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    brian eiland Senior Member

    I don't have a fax machine any longer, but if necessary I could get one that you might send it to. As an alternative, perhaps your daughter could scan the material and send it via email? ...or even post it on the form.

    I'll send you my email address via private message here on the forum.
    Brian
     
  6. brian eiland
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    brian eiland Senior Member

    I was just visiting another forum (CruisersForum) and ran across a few older postings of mine where I was defending the use of my rig design. thought I would post a few excerpts here:

     
    Last edited: Jun 9, 2015
  7. markstrimaran
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    markstrimaran Senior Member

    The quiet sound of no motor.

    I really like your ideas Brian. My preference would be a 30' trailer able aft masted trimaran. I see my self doing a lot of inland lake retirement fishing. With a blue water capable boat.
    Ideally road width legal. Probably have to be custom built by a reputable builder. This might be a difficult thing to do. As how many builders have ever tried. I am 43 and don't have the time for a self building a 30'.
     

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  8. brian eiland
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    brian eiland Senior Member

    But there is no real need to break the sail area down into 3 sails for such a small boat. In fact ketch type rigs don't really make a lot of sense on anything smaller then 40' ,...in my opinion.
     
  9. Kojii
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    Kojii All is remodelling

    Agree for most hulls but Voss did it w/ three gaff heads

    http://en.wikipedia.org/wiki/Tilikum_(boat)
    I read his book when I was a kid and have been to the museum a few times. It is a bit mind boggling to think what he did in this little canoe. May be some ideas here.
    Hull was long and narrow canoe.
    Less likely to lose one big mast, easy to balance effort, little BOOMs...
    Fun read.[​IMG]
     
  10. CT249
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    CT249 Senior Member

    What was the "John Westell principle"??

    There's a Sigma 9 trimaran that seems to be listed at 97 in the Bodensee yardstick. The F27 (about 1200kg) is 88, Dragonfly 8000 and Sprint are 85, so a 700kg 30 footer that has a rating of either 84 or 97 doesn't seem to demonstrate particularly high performance, does it?
     
  11. pogo
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    pogo ingenious dilletante

    The Sigma was an offshore cruising trimaran of 28' with full standing headroom, weighing 1300kg . She had more interior Volume than an F27 of the same weight .
    DF 8000 and Corsair Sprint are much smaller Boats.
    The 9m Offshore Racer (also with the Westell principle) and also designed by Wortmann is another boat that weighed 750kg.

    Yardstick is an imperial system. One can't trust a yardsticknumber evolved only from one (1) boat's result(s), as with the Sigma on Bodensee.

    pogo
     
  12. brian eiland
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    brian eiland Senior Member

    Arvel Gentry's passing & a Legacy of His Articles

    Arvel Gentry's passing & a Legacy of His Articles
    From his original site,

    Arvel Gentry has just recently passed away, but thank goodness someone has taken the job on to preserve his numerous papers. Check out the forum subject thread with a number of links to his papers:
    Arvel Gentry's site

    As is mentioned on the first posting of this subject thread that old website link is no longer valid. Rather have a look here for some fascinating articles of his:
    http://arvelgentry.jimdo.com/articles/



    PS: This is gentleman who's work convinced me I was on a good path to pursue my predominately headsailed rig.
    Brian Eiland
     
  13. brian eiland
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    brian eiland Senior Member

    Don't Use the Main(sail)

    I had forgotten about this subject thread that appeared over on another forum, and I just happened across it this morning. I think some will find there is a lot of talk and documentation where folks just opt to NOT utilize their mainsails:
    Don't Use the Main
    http://www.cruisersforum.com/forums/f48/dont-use-the-main-115978.html

    What surprised me further is that almost none of these participants in that discussion bothered to reply to my late posting of my mainless aft-mast rig??
     
  14. brian eiland
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    brian eiland Senior Member

    more Arvel Gentry & Wing Keels

    Just this morning another poster came up with an older article concerning Mr Gentry and his involvement with keels on America's Cup boats.

    http://articles.latimes.com/1986-08-31/magazine/tm-14767_1_silver-ewer-baron-marcel-bich-america-s-cup/4

    This was both interesting history, and brought another question to my mind,...Where is this wing-keeled technology today in our boating scene, racing or cruising :?:
     

  15. brian eiland
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    brian eiland Senior Member

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