Axe Bow

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

  1. jehardiman
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    jehardiman Senior Member

    No, this is incorrect because, everyone, no matter where their place in the process, is important to the process and can cause failure. The longer you spend in the field, the more this is apparent to you.

    What a bunch of smarmy, apologist, not my fault, not my lane, drivel! It didn't work at Nuremberg, and it won't work here with me. It only takes one weak person for "checks and balances" or "maximising the chances to catch errors" to fail as multiple NSTB, MAIB, and other accident investigation show. Accident investigators think of the accident as a chain of events, but that is not true, rather the accident is the failure of the chain.
    For a single structural weld, here is the chain off the top of my head....each one of these is a recordable permanent record calculation, certification, verification, or inspection....and a ship has 10's of thousands of these.

    Concept SOR->Concept size->Concept SS->Preliminary lines->Preliminary arrangement & weights->Final Lines->Equipment and Structural weight loads->Launching loads-> Berthing Loads->Wave slap->Framing->Final weights->Hull bending SS and speed analysis->Hydrostatic loads-> Hydrodynamic loads->Plating Diagram->Joint engineering->Platten cutting->Plate cutting temperature->Apprentice training->Joint angle and edge prep->Rigger training->Rigger->Shipfitter training-> Temperature on the ways->Block fitup->Plate fitup-> Hull straightness->Joint fitup->Joint inspection->Welding specifications->Welder and Weldor certification->Weldor inspection->Weld gas cleanliness->Weld rod temperature->Weld rod moisture->Root pass inspection->Backgouge->Backgrouge inspection->Interpass temperature->Interpass cleanliness->Final weld profile->Final weld NDT->Weld closeout->Surface prep->Base coat and cure->Base coat inspection->Top coat and cure->Top coat inspection->Launching inspection->Post -Launch inspection.

    The failure of any link in this chain can result in the loss of the vessel and all aboard...and note it starts at the Concept SOR...which is why many fishing vessel conversions fail often with loss of life. Everyone involved, from the clueless executive that pitched the concept, to the apprentice who did the weld prep is part of the chain that makes up the safety of the vessel. If you don't feel this way, get out of this profession before you kill somebody.
    Alik said it best
    <Note, I see Ad Hoc posted as I was writing this...but similar in tone>
     
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  2. CocoonCruisers
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    CocoonCruisers Junior Member

    Alik, AdHoc & Jehardiman,

    thanks for you valuable input as in so many other threads. Believe it or not, there is actually very little that i disagree with in what you write. No offense intended of course, sorry if the "dusty" sounded a little harsh. I wrote that as a question, not to impose an other view than you defend, but to question the limits of 'the classic definition' of a NA -that the op has never claimed to be- in the current evolution of tech work environments.

    That is a full high-level spin around the design spiral. I would have called that a preliminary design.
    I'm sure that process is a perfect fit in an environment that seems to be interative optimisation within a well-established line of ships, with clients that are either existant or at least known/expected as a category.

    What tz3dcom shows is far less complete obviously. The main question it seems to answer so far is if one can fit the usual hotel functions into a particular styling proposition. But that is an essential question in a boat which' two main functions are to be a luxury hotel, and to represent the myth of some kind of ship to the guests. Now he seems to be in a first quick check for pitfalls in his approach that isn't overly wild for the genre actually. And then i suppose he'll move on to a preliminary design if it passes a few sanity checks and if he can find the resources for that phase.

    That is rather subjective i think. To me, after 25 years of heavy internet usage and in an age of omnipresent publicity, deep fakes and AI writing music and drawing oil paintings, form doesn't mean much anymore. I try to look right through it and try to adjust to the emittent's language, just as everyone here does as proven by the quality feedback. To me it's not an annoyance.
    Of course, if the point was to discuss more specific technical matters concisely, napkin sketches could often turn out superior.

    Sure, but i didn't see the op claim that it is finished and sound and safe at this stage. I'd think that someone who puts his choice of type of bow up for public discussion is clearly signalling a work in progress, and reasonable humility in front of what he doesn't know so much yet. He didn't pretend he'll finish it alone.

    We do disagree on that one, at least gradually. Yes, of course we have to make sure everyone involved in the process spends a lifetime of continuous learning to eliminate points of failure in his role and beyond. Does that mean that it is realistic for everyone to take general responsibility for such a complex project ? I don't think so; cost pressure is a constant so you'll always work with folks that don't have the best capacities, some are still learning, some have roles in the process that are too far from production to allow to keep up with such matters at a meaningful level etc etc. Does it mean that a highly experienced generalistic NA can take general responsability for such a complex project ? Well i'd say yes to some extend because society needs accountability in a legal sense, and because he'll be the best guy for the role. But no because no one is infaillible, and because the complexity of larger vessels in such a hostile environment and over such a long time is largely above what anybody can thoroughly control alone: individually you can strieve for responsibility and i sure hope everybody does, and you can represent it but that is not enough. So i think the main way we can take on security is collectively, as we do with regulations, surveying, seamanship, education, R&D, better and better collaborational tools, supportiveness, efforts to bust corrupt organisational behaviour like in the 737 Max debacle, and yes, perhaps the occasional horror story as a reminder.
     
    Last edited: Aug 11, 2020
  3. Alik
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    Alik Senior Member

    There is a problem with Your definition of Concept Design. Imagine, these pictures sent to the client, he likes them and approves them, and then it is almost impossible to change his mind. Then, naval architect is hired to do the calculations and engineering - but where his responsibility starts? Just design the structure and check stability, that's it? But who is responsible if the parameters of craft are not optimum, who is responsible for common sense of safety? Maybe with selected length and declared speed the craft will operate at hump of resistance? Or should the beam be increased, to enable planing? Or for catamaran - will the spacing between hulls be optimized for speed? And for safety - aren't we having too many openings and 'beach clubs' on this yacht, she is supposed to do ocean passages? Many questions like that - if the original designer never though about those, who will?

    If the client comes to my office with 'pictures', we just say: sorry we are not doing this, unless we start from scratch.

    Yacht design is a solution of complex task, involving appearance, functionality, comfort, performance, safety, production technology, economics... Not just drawing sleek profiles!
     
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  4. CocoonCruisers
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    CocoonCruisers Junior Member

    Alik, i totally agree it is not a good idea to sell it as is.
    (I doubt it was the current goal actually. I'm assuming he already has other parts of the homework done, i see him working on feasibility aspects and i guess/hope he or some team rallying around the idea will do more. By 'if it generates some interest' i meant fishing for development partnerships at least as much as final clients. Asking one seemingly naive question about an uncommon bow form doesn't disqualify him from that, does it ?)
     
  5. Pericles
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    Pericles Senior Member

  6. jehardiman
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    jehardiman Senior Member

    Always liked the Sea Knife concept. Now someone has gone and fitted roll dampers to it, rolling being its major issue. There are some problems that can be solved with horsepower.
     
  7. Pericles
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    Pericles Senior Member

    Horsepower. :cool:

     
  8. Alik
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    Alik Senior Member

    Would like to see the yellow one going down following wave ;)
     
  9. Pericles
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    Pericles Senior Member

  10. Pericles
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    Pericles Senior Member

    The XSV20 is a catamaran with a wave piercing prow.
     
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  11. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Not to jack this thread TOO bad, but I can't help noticing that whenever a private firm writes a contract they have their lawyer see if it will "hold up in court" BEFORE they sign it or otherwise employee it. Whenever a law gets ruled "Un-Constitutional" that must mean no one thought before passing it, but most of the people passing laws are themselves lawyers. Private lawyers write up Contracts all the time that are new, weird and different to do weird things but are crafted to remain Constitutional and legal.
     
  12. Ad Hoc
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    Ad Hoc Naval Architect

    If the question was asked with no reference to his 'concept' and posting the image of said concpet, then I would agree.
    Yet... the 3D image is there -

    Thus a question about the shape of bows and their merit, does not need a reference image to their 'concept' in the technical debate... ergo, one is fishing for comments on their own 'concept'.
     
  13. bhnautika
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    bhnautika Senior Member

    Tz3dcom you may want to have a look at the super yacht “predator” from the feadship yard back in 2008 . All those budding designers out there look up Jon Bannenberg to see what you could end up doing.
     
  14. brendan gardam
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    brendan gardam Senior Member

    do you actually think the designers did not think of that.
     

  15. Alik
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    Alik Senior Member

    I don't care what they think or not think ;) I just want to see how it goes down wave.

    PS We tested RC model with same bow shape 10 years ago...

    PPS Very often, those breakthrough designs are created for stunning pics in press only, not for real operation. Not all, but quite often.
     
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