Axe Bow

Discussion in 'Boat Design' started by tz3dcom, Aug 6, 2020.

  1. tz3dcom
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    tz3dcom 3D

    Hello all,

    This is a new 36.6M conceptwith a Axe Bow design, Does anyone know this type bow has any advantages and disadvantages in this size boat ?

    Here is the exterior 3D VR Demo

    KeyShotXR http://tz3dstudio.com/360/36m/36m.html

    Thanks for your comment.
     

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  2. jehardiman
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    jehardiman Senior Member

    Depends on the design seaway. In some seaways it works, in others it will sink the vessel...YMMV.
     
  3. Squidly-Diddly
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    Squidly-Diddly Senior Member

    after that Italian Navy ship with what is basically a "double bow", I'm thinking maybe a quadruple bow "sawtooth" might be about right. Idea would be to get a mix of wave piercing and wave defection but always having defection as the last operation to next too much spray coming over the bow. Double the number of points of bow in pic.
     

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  4. DCockey
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    DCockey Senior Member

    Am I correct that your studio spent time creating a design, and are now asking if a principal feature of the design, the bow shape, has any advantages? That is an interesting approach.
     
  5. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Its a well founded business practice. The iconic B-movie producer Ed Wood would send out just the POSTERS of new movies to theaters across the nation but wouldn't MAKE the movie unless he got the orders, and he'd tease suggestions from theater owners so they get what they wanted, more or less.
     
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  6. CocoonCruisers
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    CocoonCruisers Junior Member

    Clearly that question may appear slightly bizarre on such a technical forum. But meanwhile tz3dcom's bow already fulfils a purpose: it sure looks cool.
    I guess the main question here is if the marketing blurb can be backed up with an actual need or advantage. (And it seems there is a bit of confusion between axe bow, as used on patrol boats, and the X-bow on some Burbon ships.)

    As for a need, i'd say no: the purpose of such a boat is for the billionnaires to enjoy the champaign. The captain will know fairly well that if they all end up puking because of high speeds in horrendous seastates (which is the purpose of the real x-bow, look up the videos), he will get fired. So in actual usage, the thing will not be driven hard enough for the bow shape to matter. And your yacht looks a little too fat and low for it to work properly anyway - the much larger and higher axe bow ocean supply ships are fairly slender.

    As for advantages, it might be a little bit softer in medium speeds, but go a little too fast and you won't see much anymore, and you'd probably risk greenwater crashing through the front windows at lower speeds than with a more classic bow.

    So i wouldn't lean too far out of the window in terms of functionality promises. BTW be careful with names that stand for patented concepts.
     
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  7. Yobarnacle
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    Yobarnacle Senior Member holding true course

    Axe bows are purposed to eliminate bow shadow.
    With high bowed large vessels, the area in front of a conventional bow for considerable distance is blocked from view. Called the "Bow Shadow".
    Vessels like tugs and other special designs, need to work close to other structures and vessels.
    Eliminating bow shadow reduces close quarters collisions.
    Sending a hand on the dock with a walkie-talkie , to take a look in front, also works, but crews are smaller and getting smaller.
    Also, axe bow makes observing forward draft marks easier, and observing the anchor when heaving up snug in the hawse hole more visible. Many times the anchor must be relowered and resnugged several times, before it twists to the correct angle for housing in the hawse pipe..
    Better visibility is the sole advantage of Axe bows. Except maybe less material used in construction?

    Because of bow shadow, navigation regulations require stationing the underway lookout as low and as far forward, as possible.
     
    Last edited: Aug 7, 2020
  8. jehardiman
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    jehardiman Senior Member

    Yeah, but without a tripping bar there is no way in Hades they are going to get that anchor up into that pocket. Where do you stow the 20 foot boathook?
     
  9. Yobarnacle
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    Yobarnacle Senior Member holding true course

    My experience is with large commercial vessels. A boathook won't faze a ten ton anchor.
    Axe bows on yachts also reduce bow shadow, though their bow shadow is minimal compared to a ship whose bow is five stories high.
    The NA will design he solutions for the small problems. NAs do that specialized work!
     
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  10. jehardiman
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    jehardiman Senior Member

    In school we were showed a photo of a situation where they were inhauling a stockless and it got caught on the bulb. The fluke was flipped the wrong way and it drove the bill of the flukes up through the plating. Really though, I doubt that any costly mega/super yacht ever uses it's anchor except to prevent itself from going up on the hard.
     
  11. tz3dcom
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    tz3dcom 3D

    What I understand that the design objectives of double bow is to reduce the weight and resistance from the bow.
    Maybe a big bow and foredeck are not neccessary in this type of navy ship as they always work in any weather and no worry the spray coming over the bow .
     

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  12. tz3dcom
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    tz3dcom 3D

    So serious .... has any example to prove it will sink the vessel ? as we know many warships with this type bow a hundred years ago. My understanding is that the increased bow part will provide the more buoyancy, more longer waterline and less the resistance. of course It will make the deck more wet.
     

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  13. tz3dcom
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    tz3dcom 3D

    yes, It did take me about 2 months to create this concept...I've been out of work this yeas :(
     
  14. tz3dcom
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    tz3dcom 3D

    Yes, Usual the billionnaires enjoy the champaign in the calm coral sea rather than the bad sea conditions.They are not sailing...
     

  15. jehardiman
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    jehardiman Senior Member

    Tz3dcom, while I understand that neophytes come to this site to learn, I abhor people coming who have yet to do due diligence in their studies.
    You are incorrect, the bow type of the pre-dreadnoughts and dreadnoughts was a ram bow, not an X-Bow (TM). If you had done due diligence you would know the difference and you would understand the issues with your forward lower deck windows is similar to the massive damage and down flooding experienced by the forward casemate guns in those ships and why they were converted to Atlantic bow in the inter-war.
    Again, this show a lack of due diligence to Naval Architecture that borders on negligent if this vessel was built. The forward windows can experience loads of between 2,000 and 10,000 psf due to wave slap because the bow provides less buoyancy. Take a look at an X-Bow (TM) and notice the height above WL and the extent of solid structure aft of the cutwater.
    Note that my comments are not to single you out, but you threw yourself up as an example of my previous saying that "there are many things that can be designed that should not be built, and many things that have been built that should not have been designed".
     
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