Reverese bows

Discussion in 'Boat Design' started by SC1, May 27, 2006.

  1. SC1
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    SC1 Senior Member

    Opinions on this bow design?
    Advantages?
     

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  2. RANCHI OTTO
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    RANCHI OTTO Naval Architect

    It depends on speed...for low/medium speed you increase the waterline length (advantage), by high speed you increase the wetted surface (disavantage).

    If you have a schock with the bow you can have a problem of water intake below waterline.
     
  3. SC1
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    SC1 Senior Member

    With a cruising speed at about 25knots...
    with identical waterline lengths a normal bow will gives a longer total lenght and also add more weight...(disvantage)
     

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  4. RANCHI OTTO
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    RANCHI OTTO Naval Architect

    The fine shape of the bow will intake green water on deck.

    the increase in weight is nothing compared to the total displacement of the ship.
     
  5. duluthboats
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    duluthboats Senior Dreamer

    If you want your boat to look like the front of a train then this makes a fine job of it.
     
  6. SC1
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    SC1 Senior Member

    Does not look like a train to me :idea: ;)
     

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  7. SC1
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    SC1 Senior Member

    But this one....:rolleyes:
     

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  8. SC1
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    SC1 Senior Member

    Like this:?:
     

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  9. safewalrus
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    safewalrus Ancient Marriner

    thats a normal phenomina, you'll find that vessel has a normal style bow when it sttles out - in her case I'd be more worried aobout the weight of the water getting caught in the pipes on the main deck than any 'splashing' on the front! But with workboats if you don't know about it you don't worry until too late!
     
  10. safewalrus
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    safewalrus Ancient Marriner

    Oh and SC1 the battlewagon had her bows that way as they were running down to a ram! saved money when hitting smaller boats!
     
  11. Doug Lord

    Doug Lord Guest

    Bow

    I like it- particulary on some sailboat designs. One of Juan K's VOR boats has a slightly reverse bow and Julian Bethwaite/Martin Billoch have drawn a fairly large mono with a beautiful reverse bow. Then there are the A class cats and
    my and Eric Sponbergs aeroSKIFF14 (see sketch under Peoples Foiler thread under "sailboats").
    Sort of a blast from the past....
    ---------------
    aeroSKIFF 14
    attachment.php?attachmentid=5297&d=1141571544
    Address:http://www.boatdesign.net/forums/attachment.php?attachmentid=5297&d=1141571544 Changed:10:12 AM on Sunday, March 5, 2006
     
    Last edited by a moderator: May 28, 2006
  12. safewalrus
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    safewalrus Ancient Marriner

    And the rams were good for sinking trojans and persians and carthaginians, how far we going back? (even before I were a lad?)
     
  13. jehardiman
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    jehardiman Senior Member

    By the time they got to building USS TEXAS, the bows were bulbed below for powering reasons. See David Taylor: "The Speed and Powering of Ships". Modern reverse bows are designed to reduce pitching moment and slamming caused by high speed in waves. However, there are other issues with stability.

    BTW I can only think of only two successful ram attacks by modern ships designed to ram in combat. All the rest were "spur of the moment" stuff mostly against submarines, and some even sank the attacker (cf. USS BORIE).
     
  14. I like the reverse bow and I am thinking long time to design a boat with this kind of stem line together with a thumb and reverse transom.
    In Italy was used in small fishing boats to allow easy landing and in order to obtain an immediate floatation thrust in rough sea condition in low deep beaches as in Liguria. These requirements were loose with introduction of the engine power in these kind of traditional sailing fishing boats as the increasing of speed it made continuous 'splashing' on deck. For this reason the reverse stem line were abandoned on this kind of "Ligurian Gozzo".
    But I am thinking at this lines for a more pleasant boat, not a working boat. So I like the idea.
     

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  15. Wellydeckhand

    Wellydeckhand Previous Member

    The Green hull what is the correct name for this type of hull?

    The other white hull is the look of a train..........................
     

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