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Getting in to the guts of a design. Unsailboat

Discussion in 'Technical Discussion' started by Codger, Mar 25, 2007.

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  1. Codger

    Codger YF Wisdom Dept.

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    Both Airship and Kalmeran referenced the Unsailboat in the following posts.
    http://www.yachtforums.com/forums/19580-post7.html
    http://www.yachtforums.com/forums/31935-post3.html
    Thanks to you both.

    I finally took a look last night. What a well-set table of information on the whys, ifs and becauses. I'm tired and feel like I've just completed the better part of a 24 course information meal, but what a feast. :D This is probably just an appetizer for some of you but I found it delicious.
    http://www.setsail.com/dashew/dashew218.html


    Gee! You'd think I'm hungry right now.
  2. AMG

    AMG YF Moderator

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    My first thought on this was; Dockwise...:D
  3. Codger

    Codger YF Wisdom Dept.

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    http://www.setsail.com/dashew/HI_CA_5.html

    "As you probably know, we spent a lot of time modeling various upwind scenarios. Using tank testing and CFD analysis, one can come pretty close to the real world with single sets of waves. But when you have complex crossing situations, as we are in right now, most of the design input comes from experience. There is no accurate way to model what we've been going through."

    I know that Hyundai and others have extremely complex sea state models. There is also a Norwegian company that has built offshore platforms that has performed some testing using models of seastates that are in the order of once a hundred year scenarios.
    Are these models just not generally available?
  4. Kruse

    Kruse Member

    Joined:
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    Location:
    Denmark
    Ultimate light battlewagon

    Battlewagon

    I find the Dashew FPB to be close to the ideal long range cruiser.

    Some aspects, often overlooked, but integrated into this design:

    - Capsize stability and self-righting ability
    - Balanced bow to stern for increased steering control in waves
    - Sharp bow “Canoe design” 6:1 with good speed potential (12-14 knots) and soft motion
    - All cabin soles above waterline, fuel and water below.
    - Centralized living and accommodation, basement for storage and systems
    - Separate large engine room, with room for work area and easy cleaning
    - Overbuild strength-wise, designed to take a real beating
    - Light but strong construction, real range of 10000nm/10kn, including use of A/C, electrics and hydraulics
    - Trim tanks, oversize rudders, roll-stabilisation with oversize fins and fish/flopperstoppers via booms

    Some of these design aspects, when presented seems obvious.
    You could wonder why some of these concepts are not used more often…:
    - When lying in you bunk, cooking, relaxing, at watch topside or at the main helm,
    you are never more than 3 meter / 10 feet from the boats center of motion.
    This translates to minimal felt motion and much increased comfort.
    The more comfortable and safe/stable the boat, the more you are going to enjoy your travels.
    - The oversize rudders and fins give you steering and stabilization in bad weather or when going slow.
    At speed, these larger surfaces have less drag / no cavitations from the smaller angles required for effect

    Absolutely worth your time to investigate
    http://www.setsail.com/dashew/do_PARADIGM.html

    Well yes, I am a fan. A lot of thought and experience has gone into this design.
    :D
  5. Highlander

    Highlander New Member

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    Milford CT
    Just about perfect

    I have been reading about the smaller one, 64' with the same strength and performance of the original. I have a lot of respect for a designer that cares about what works!
    So many production boats are not equiped to be used. Poor ground tackle systems. gear storage, dinghy storage and launching etc.
    One of the photos showed kayaks mounted on the roof. That, I like alot.
    The thing is that the jump from coastal cruising to passagemaking is a big one. I want to get a price but am not ready to go.

    Still dreaming

    Carl
  6. Loren Schweizer

    Loren Schweizer YF Associate Writer

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    BC Research, which does a lot of wavetank testing, and is in your neighborhood (Vancouver), might be able to shed some light.
  7. brian eiland

    brian eiland Senior Member

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    Dashew's FPB

    I find his approch to creating an ocean going vessel to be superb.

    I thought a photo in this thread might be appropriate to draw attention to the subject matter.

    ...and "Why Are We Doing This?"

    Attached Files:

  8. Codger

    Codger YF Wisdom Dept.

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    I go back and look at the site regularly. Dashew's explanations just seem to make sense to me. I tried to visualise what the result would be if Dashew had had a hand in the design of Skat.:)
  9. Kruse

    Kruse Member

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    The design of the FPB64 has come a long way.
    The latest editions to the design has made it even better.
    That the Dashews can design a boat that will behave as good or better at sea than the first (larger) FPB is astonishing.
    This boat is the one.
    At least 4 boats seem to have been commissioned so far and the plans for a second production run is in the works.
    I keep going back there, hoping to get a glimpse of the latest news.
    Every little addition or change always surprises me. I thought I had an idea of what could be changed, and they do something totally different but also better. As close as I know a boat to be ultimate, this is it.
    There is not much you can change without compromising efficiency or agility and comfort. Amazing!:D
  10. Codger

    Codger YF Wisdom Dept.

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    From what I can gather the Dashews have cruised somewhere in the range of 200,000 miles and that speaks volumes to me.
    I wonder how many other designers/builders have actually lived and cruised aboard their creations.
  11. Ward

    Ward Senior Member

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    BC Research

    I realize I'm replying two years later, but BC Research was already gone back in 2008. I don't remember when the company went under, maybe around 2005? Some remnants of the company carried on under new names in the BC Research building, but the last of them was shut down early in 2008. I worked at the building next door in 2008, and as I biked or drove by each day, I watched them tear down the BC Research building and started putting up condos.
  12. brian eiland

    brian eiland Senior Member

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    I fear that the same thing is happening in Annapolis Md....the water front marine zoned business areas are slowing being converted to CONDOs and townhouses (I even owned one :eek: ). I believe this current depressed real estate market is the only thing that slowed the processes down over the past 2 years.


    Interesting question. But in reality most designers don't make enough money to be able to afford their own creations