Bow sprit in high seas.

Discussion in 'Sailboats' started by Shack, Oct 12, 2009.

  1. ancient kayaker
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    ancient kayaker aka Terry Haines

    I wonder if there is comparative data of her performance under the two different rigs and race vs cruise configuration? It's not often we get the chance to see such a change on the same hull.

    Mike's story of ramming the dock to stop the boat reminds me of a story about a great canadian, rear-Admiral Bob Welland. When worked in Ottawa a few decades back he was the company's GM and many stories both true and apocryphal went the rounds. My favorite was of his habit of approaching the dock at full speed in a destroyer during WW2 and ordering full reverse, just stopping in time. His judgement was impeccable.

    Then he received command of a cruiser and tried the same thing. Standing stiffly on the bridge, No. 1 expressed the opinion "we're going to hit aren't we" and Capt Welland agreed. Fortunately alert crews onboard and on the dock managed to get lines wrapped around a bollard or two and helped to stop the brand-new ship inches from embarassment.
     
  2. Perm Stress
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    Perm Stress Senior Member

    by BeauVrolyk:
    BeauVrolyk "I would hold that there are a number of advantages to bow-sprits, but that modern boats probably don't need them, except down wind."
    Agree...
    the problem (or just property, or feature -depend on point of view) with modern boats is that most of them are perfectly balanced for upwind or very close reach work, while for any course further off the balance simply disappear...
    Here is the place for bowsprit with additional sail!
    And, if not the measurement J (base of fore triangle), I believe it would far more widely used.
    I will try to post a photo of 45 feet boat I was skippering for time long enough to invent a makeshift bowsprit for her.
     
    Last edited: Nov 6, 2009
  3. Perm Stress
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    Perm Stress Senior Member

    There is a picture..

    This boat is not quite modern by today's standards, but still not oldtimer either.
    She has quite a long keel, separate rudder with narrow full depth skeg.
    And is a bermuda schooner as could be seen.
    (And, by the way, her high roached foresail was ordered half a year before first pictures of similarly rigged big schooners were published in Yachting World magazine. :cool: )

    What was an effect..:

    Before: close hauled, sometimes close reaching you could lash the wheel for hours, no matter if there is any wave or not. But not for beam reach or further.

    After: you could lash the helm for hours up to broad reaching (~135 TWA).
    Also speed: in light winds, at about 130-150 TWA, Force 2-3, hoisting this flying yankee on a bowsprit is a difference between ~3.5 and ~5.2 knots.
    Out of all proportion to additional sail area.
     

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  4. ancient kayaker
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    ancient kayaker aka Terry Haines

    That is an amazing improvement. From your previous post I gather much of this results from better balance. Does the extra efficiency come from sail power or reduced rudder drag?
     
  5. Perm Stress
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    Perm Stress Senior Member

    "That is an amazing improvement. From your previous post I gather much of this results from better balance. Does the extra efficiency come from sail power or reduced rudder drag?"

    I wish I know this...
    I think from both, with more pure power adding better part. This is based on just a feeling of uninterrupted, continuous pulling power such setup is developing. Less rudder work also should have something to do with it.
    Also I have noticed many times in different boats, that at broader appearent wind angles, multi sail setup is more resistant to stall, -boat much less often experience temporary drops in speed...
     

  6. CHARMIANOFPOOLE
    Joined: Nov 2009
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    Location: MILLBROOK CORNWALL UK

    CHARMIANOFPOOLE New Member

    217.JPG

    Hi,
    Our boat "Charmian of Poole" is based on a British Pilot Cutter & has a deck length of 38' with a Bowsprit extending 20' from the stem.
    In heavy sea's we have to withdraw & secure, reef the Gaff Mainsail & only use our Staysail hanked onto the stem forestay.
    Our mast carries a fidded topmast of 22' & we have found that when the Bowsprit dives into the water the running stay attached slackens badly & on the upward motion the Bowsprit bends almost to the point of breaking due to no tension on the running stay. The Stay snaps taught & this in turn bends the Topmast forward straining the running backstays.
    A Good example of what this can cause if not checked early is to be found on www.workingsail.co.uk under the heading "Yard News"
    The Pilot Cutter "Agnes" was on passage from the Isle of Mann UK through the Irish sea flying her Jib from her Bowsprit & a Topsail. She dived into a trough snapping her Bowsprit & bringing down her Topmast.
    Regards
    Lez Arkell
     
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