Aftmast rigs???

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

  1. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    Good question.

    The heeling angle would increase because the heeling moment would increase.

    And this would happen because the mast will be on the starboard side (it would be on the port side, if I were left handed).

    When the boat heels, the down wind side (leeward side) gets pushed down by the heeling arm of the sail. When that happens, the windward side rises up a bit.

    If the mast happens to be on that side, it rises up a bit too. When this happens, the Center of Area (CA) of the sail rises up as well. This, in turn, increases the length of the Heeling Arm (HA). So, if the sail is producing as much heeling force on this tack as it was on the port tack, the Heeling Moment will be greater.

    If the Heeling Moment is greater, the boat will heel over further.

    I hope this helps.
     
  2. brendan gardam
    Joined: Feb 2020
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    Location: east gippsland australia

    brendan gardam Senior Member

    Thanks sharpi, iIdidn't realise the mast was off center. Now it makes sense.
     
  3. brian eiland
    Joined: Jun 2002
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Too bad Eric is around to defend himself. He's gone out sailing (cruising) around the world with his wife
     
  4. CT249
    Joined: May 2003
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    Location: Sydney Australia

    CT249 Senior Member

    Brian, two points;

    1- Eric did not give those he called “insane” a chance to defend themselves.

    2- If Eric is going to use such language against others then it is hypocritical to complain when similar language is used in reply

    3- I put this information before Eric on this very forum. He admitted that some of what he said in his article was wrong or said he had just got the info second hand. He still left the article on his site, containing derogatory comments that he admitted here to be untrue

    4- Are you claiming that I made factual errors? In which case, what ones? When it comes to the remarks on rating rules, for example, I checked old books and confirmed without doubt that some of Eric’s claims were simply not true.

    Why should derogatory and incorrect claims be allowed to remain unchallenged and uncorrected on a site about the subject?
     
    Last edited: Jul 23, 2020
  5. brian eiland
    Joined: Jun 2002
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    @CT249,
    To tell the truth I am tired of arguing with you about this stuff.

    The simple truth is there are likely numerous new (and radical) ideas that might not have come to the sailing world had everyone 'conformed' to the rating rules of racing,...or 'convention thinking'.

    Do you think these ideas would arise in the conventional rating rule world?

    1) Saphira
    Atlantic 70F https://www.chriswhitedesigns.com/atlantic-70f
    [​IMG]


    2) https://www.boatdesign.net/threads/understanding-wing-technology.34697/page-22#post-874007

    3) Eagle 53
    Eagle Class 53 Catamaran Foiler https://www.boatdesign.net/threads/eagle-class-53-catamaran-foiler.60758/#post-873270

    Etc, etc

    PS: Yes Eric and I and a number of other fellows thought the 'conventional sailing world' was mired in a bunch of horse manure at times.

    The convention world stifled progress, not intentionally, but rather as a result of their efforts to handicap racing.
     
  6. CT249
    Joined: May 2003
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    Location: Sydney Australia

    CT249 Senior Member

    For one, you're setting up a strawman there, Brian. I never said anything that claimed or implied that those craft could be created within most rating rules - but that is completely ignoring the point that there are many OTHER areas of sailing that do NOT have such restrictive rules. Many such areas, like Skiff sailing, Moths, Canoes, shorthanded yachts, sportsboats, etc etc etc are well funded and have very high profiles. To somehow assume that some ban on things like roachy wingmasts in SOME classes has lead to sailors from ALL classes to be "blind" to them is incorrect, illogical and insulting.

    The underlying assumption that what is banned in some "mainstream" classes is thereby made invisible or dramatically restricted is utterly untrue, as many examples can prove. So even if it had been true that rating rules banned roachy wingmast rigs, for example, that did NOT mean that the sailing world would have been "blind" to them. Perhaps the East Coast USA sailing world may have largely ignored them, but that is far from the entire world.

    When I was a kid, for example, my first boat had no backstay, a roachy fully battened main, and a rotating mast. It was one of the most popular classes in the country. We had wingmasts on kid's boats, mum-and-dad boats, and roaches on most boats. There were six classes of wingmast/fully battened roachy main boats within about a mile of my home. To say that the people who grew up in this and similar environments were "blind" to things like roachy mains and wingmasts is just ridiculous and untrue. Okay, maybe some people grew up where IOR, Flying Scots, Stars and Snipes ruled, but those people should learn that their experience is not that of the entire world.

    As already noted, most of the world's most popular classes (including the most popular class of all, the two most popular dinghy designs, the most popular dayboat keelboat, the most popular cat, etc) have "unconventional" rigs. It is silly to claim that the many people who come from such environments are "inbred" with the belief that we need wires and triangular mains.

    Yesterday, my boat was in a line with two other yachts. All three of the yachts were owned (or in one case perhaps just sailed) by people with years of experience with wingmasted roachy rigs on both monos and cats - and all three of them have conventional rigs. No one was "blind" or "insanely conservative"; in fact we may have more time with wingmasts than you or Eric do. We chose different rigs for different uses because we have lots of experience with each type and we know their benefits and issues.

    I don't really see why telling the truth, and implicitly defending people from abuse such as claiming they are "insanely conservative" and "blind", is seen as anything to be concerned about. The truth is surely a good thing.

    I don't really understand why Eric is allowed to sling **** at people for being "insanely conservative" and "blind", but it's said to be offensive when he gets called on it. He's not a protected species or a special case. If he is going to write stuff that is not true and to insult people, then he cannot get offended when the truth is stated.
     
    Last edited: Jul 26, 2020
    brendan gardam likes this.
  7. gggGuest
    Joined: Feb 2005
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    gggGuest ...

    Actually its simple nonsense founded on blinkered eyes and lack of awareness.
     
  8. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Brian, I just came across this article from almost 40 years ago about wind assistance for commercial shipping, and I thought you might be interested in it..
    A FRESH WIND FOR SAIL POWER https://www.nytimes.com/1981/12/06/magazine/a-fresh-wind-for-sail-power.html

    They mention Jesse Briggs and SAILA - I had a subscription to the SAILA newsletters in the mid 80's, but sadly something happened, and they were no more.
    Later on they also mention Lloyd Bergeson and the Windship Development Corporation - I will attach a copy of a paper that he presented at a conference in 1985 on wind assist developments for commercial shipping.
     

    Attached Files:

  9. Will Gilmore
    Joined: Aug 2017
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    Location: Littleton, nh

    Will Gilmore Senior Member

    Last edited: Aug 13, 2020
    bajansailor likes this.

  10. brian eiland
    Joined: Jun 2002
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Very interesting submission,...long article that I will have to return to and read more thoroughly.

    Perhaps it would be best posted on this other subject thread??

    New Age Trawler/Motorsailer; Kite assisted PowerYacht

    New Age Trawler/Motorsailer; Kite assisted PowerYacht https://www.boatdesign.net/threads/new-age-trawler-motorsailer-kite-assisted-poweryacht.20319/
     
    bajansailor likes this.
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