best stern type

Discussion in 'Boat Design' started by urisvan, Mar 9, 2007.

  1. urisvan
    Joined: Nov 2005
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    urisvan Senior Member

    let's discuss the stern types. the criteria is seaworthiness. considering about a traditional vessel which type of stern could be the best in seaway? i mean pitching, deckwetness, and ease to control in very heavy sea conditions.
    first i want to write some of my guesses; i say guess, because i don't have practical knoweledge. please confirm if below is true or not:

    a north stern type double-ender probably pitch heavily and the pitching movement will not damp so easily because it doesn't have much reserved buoyancy and also not too much area at aft to damp the movement. and it will suffer deckwetness in overtaking seas on downwind courses. but it should be rather safe in stormy conditions, because it will not bow bury, and will not yaw in downwind sailing.

    canoe stern double-ender should be better as being less pitching and deck wetness as being more buoyant stern. and the pitching will damp more easily because of the area of the stern. i think it will be safe in heavy seas because of easy control.

    counter stern(not a double-ender) with a small transom also will behave like canoe stern but in heavy seas and at downwind course, it will have more tendency to yaw and the waves will hit the stern and push the boat so it will need more carefull steering(which shouldn't be easy in very heavy, stormy weather).

    raked or vertical wide transoms will behave different. when the boat heels the wide stern will make the boat trim also. it will behave better than northern type stern for pitching and damping of pitching, but will be worse than canoe stern or counter stern in this context. it will prevent the sea coming to cockpit(a dry cockpit) but in survival conditions it will be more difficult to sail it, because of the tendency to yaw and broach in downwind courses.

    till now i can say that in survival conditions, the northern type will be best, a wide stern will be comfortable in a hard breeze. canoe stern or a counter stern with a small transom will be an optimum choice. of course canoe stern and counter stern types will have some variations too. for example long canoe, short canoe(or one in the middle), long counter stern, rather short one. counter stern will a reverse raked transom
    of couse there are a lot of different sterns
    i quit now, and waiting to hear some from you.
     
  2. urisvan
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    urisvan Senior Member

    hii

    isn't there anybody?
    any suggestion or confirmation will be valuable.
    my point is to find "the favourable stern type concerning seaworthiness"
    maybe i should discuss this topic in the stability section.
    i am waiting to hear from you.
    bye
     
  3. FAST FRED
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    FAST FRED Senior Member

    My preference is for the std stern with a bit of overhang.

    The hassle with the canoe stern is it has a lower hull speed than a conventional, in other words it drags more ocean along at speed.

    Since speed is easy in high winds the problem is the energy added to the waves astern can cause them to break early and at lower hight.

    Not grand with a stern with little extra flotation . More waves washing in from astern over the back pointy end doesn't sound inviting , or seaworthy to me.

    FF
     
  4. urisvan
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    urisvan Senior Member

    hi fast fred
    this is your sentence(in some threads i see that they put the quatotions in a box, how do they do that):
    "Since speed is easy in high winds the problem is the energy added to the waves astern can cause them to break early and at lower hight."
    how does the energy can be added by the stern?
    cheers
     
  5. FAST FRED
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    FAST FRED Senior Member

    The boat requires energy to move the water aside to go forward, the engine or sails produce it.

    As the pushed aside water combines in the rear , it contains the energy , as does the water pushed down that returns to the surface aft.

    This can make a near breaking wave BREAK.

    FF
     
  6. urisvan
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    urisvan Senior Member

    fast fred,thank you very much for your logical explanation. it sounds scientific.
    so don't you vote for a double-ender, either it has canoe stern or colin-archer(or northern) type stern?
    some thinks that, double-enders are the most seaworthy boats, especially in very heavy oceans(for example northern sea). i wonder why do they say like that, maybe they had an experience and survived and believe that it was their luck sailing in a double-ender. maybe they even didn't sail a transom stern boat. who knows. or maybe they are wright. i really don't know but wonder too much. if i had a chance i would like to sail all kind of boats in all weather conditions. i am very suspicious and curious. every scientific explanations and sailing experiences will be very valuable to me.

    "if instead of sending the observations of able seamen to able mathematicians on land, the land would send able mathematicians to sea, it would signify much more to the improvement... of the safety of men's lives on that element."
    Sir Isaac Newton
     
  7. FAST FRED
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    FAST FRED Senior Member

    double-enders are the most seaworthy boats, especially in very heavy oceans

    Thats why many rescue services used to pick this design, they can be more easily rowed backwards to assist folks in the water, and waves pick up no energy from a stopped boat.

    FF
     
  8. urisvan
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    urisvan Senior Member

    canoe stern boat is also a double-ender boat. isn't it?
    do you mean northern(colin archer) type boat is seaworthy and canoe stern is not?
     
  9. FAST FRED
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    FAST FRED Senior Member

    ANY boat with a pointy rear is less seaworthy than a std counter transome boat.

    The heavier the more water dragged into the boat at speed.

    FF
     
  10. kach22i
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    kach22i Architect

    A surgar scoop is safest, so you at least have a chance of crawling back on board by yourself, right?

    [​IMG]
    [​IMG]
     
  11. urisvan
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    urisvan Senior Member

    hello fast fred,
    are you fooling me.:D. is your sentence ironic? you said that:
    "double-enders are the most seaworthy boats, especially in very heavy oceans
    Thats why many rescue services used to pick this design, they can be more easily rowed backwards to assist folks in the water, and waves pick up no energy from a stopped boat."

    and after one day, you said:
    "ANY boat with a pointy rear is less seaworthy than a std counter transome boat.
    The heavier the more water dragged into the boat at speed."

    doesn't pointy rear means double-ender?
    :confused:
     
  12. urisvan
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    urisvan Senior Member

    hi kack22i
    at first your touch sounds funny because i didn't hear anything like that. but then i thougth that it is logical. can't you climb from the rope?
    thank you.
    see you
     
  13. kach22i
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    kach22i Architect

    The shorter the climb in wet heavy clothes the better, right?

    So the lower the shelf or the sugar scoop or entry deck level the better, that's all I'm saying.

    I guess you could leave a ladder dragging, not a good idea though.
     
  14. urisvan
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    urisvan Senior Member

    waiting reply

    hi fast fred,
    i am waiting a reply from you.
    and also i wait opinions from the other guys about double-enders.
     
  15. xarax

    xarax Previous Member

    Pitching is a problem only for boats with very high masts and very deep keels. In fact, double enders do not suffer from excessive pitching, They suffer from limited deck area... As they went out of fashion, they now suffer from old-fashioned looks, too...:)
     

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