Seaworthiness

Discussion in 'Stability' started by Guillermo, Nov 26, 2006.

  1. Guillermo
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    Guillermo Ingeniero Naval

    Thanks fcfc.
    I want to highlight this:

    10. At 2120 hours (local) one person was on the helm and 2 were below. A single wave knocked the boat to 90 degrees. The boat did not immediately right, and a second wave that came quite quickly after the first wave rolled the boat to 180 degrees.

    11. The boat seemed, in the words of the skipper, quite comfortable at staying inverted....

    16. About 10 minutes later, the boat righted itself. The delivery skipper speculates that once the mast broke underwater, the next wave shoved the boat over enough for the keel to go to work.


    I find amazing there are no commentaries at all at the "Lessons learned" about the fact that a Class 1 boat stayed inverted for 10 minutes. What about the target of 2 minutes maximum, after the lessons learned from the Fastnet '79?
     
  2. fg1inc

    fg1inc Guest

    The seaworthy boat is the one that will take care of you when you can no longer take care of it.
     
  3. Crag Cay
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    Crag Cay Senior Member

    Abbey Sunderland's boat wasn't a Class 40.
     
  4. MikeJohns
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    MikeJohns Senior Member

    How different ? its a similar vessel ULDB deep bulb open 40 planing design, but its rating was for Open 40, I was wondering whether it would meet class 40 anyway? It is confusing but there wouldn't be much between it would there?



    That account of a class40 is revealing, 10 minutes inverted and the crew couldn't get back inside. It makes a mockery of the tests in smooth water with the crew moving weight around from inside to re-right the vessel.
     
  5. fcfc
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    fcfc Senior Member

    No, you make a mistake.

    Class 40 edition 2010 does not need any rerighting (OSR 1 only). The boat that capsized had NO rerighting test. Note this is the first documented class 40 capsize since its existence (6 years).

    Rerighting ability (OSR 0) is currently only needed for around the world race. I guess it will probably be included in future releases of the class 40 rules.
     
  6. MikeJohns
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    MikeJohns Senior Member


    But if you can't get back into an inverted vessel to shift water into side tanks etc then reliance on those sorts of features are not very reliable if you have to be inside to operate them. I can see if you were on deck in gear with buoyancy you'd find it hard to get back in.
     
  7. BATAAN
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    BATAAN Senior Member

    Racing has really played havoc with sensible seaworthiness in the name of speed, and winning races of course. Here's something different that's slower but gets there, and doesn't need a huge crew of testosterone. I know racing has advanced sailing theory and practice tremendously, but some things seem a silly waste of money in the pursuit of "I'm faster than you are". Fine, but do it the old way of clipper ships, set a record while carrying hundreds of tons of paying cargo and then I'll be impressed with all the engineering.
     

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  8. Mikey
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    Mikey Senior Member

    What an excellent phrase: "Racing has really played havoc with sensible seaworthiness in the name of speed, and winning races of course"

    The sad thing with it is that ordinary customers often don't understand the negative aspects - comfort also included
     
  9. marshmat
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    marshmat Senior Member

    Interesting points, Bataan and Mikey.

    I think it would be very interesting to see a cutting edge racing class, a la VO 70, with one additional requirement in the rules:
    "The boat shall, at each port of call, take on eight thousand (for example) kilograms of locally produced cargo, to be offloaded and sold at the next port of call." If the crew want to shift the cargo around for ballast, let them- as long as they do it themselves.
    Bring the old days of commerce back into it, encourage boats that can carry a load, get the fans buying trinkets and souvenirs from earlier in the race. Want a more comfortable motion in the next generation of boats? Make them carry fragile glassware and china as cargo. Could be interesting....
     
  10. BATAAN
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    BATAAN Senior Member

    Absolutely. Thank you Marshmat. I love it. Make the designers start earning their fees by doing something a little harder.
     
  11. Landlubber
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    Landlubber Senior Member

    Bataan,

    Will your boat self right after being inverted?
     
  12. Guillermo
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    Guillermo Ingeniero Naval

    Thanks Bataan and Marshmat for bringing in a fresh look to seaworthiness :)

    Here a different approach:

    "If you think that I am mad then you should meet my mother"
    http://www.dixdesign.com/steward.htm
     

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  13. marshmat
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    marshmat Senior Member

    A different approach, Guillermo, yes.... although not one I would care to take myself! A 19-foot trailer sailer in the open ocean is certainly a test of seamanship.
     
  14. BATAAN
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    BATAAN Senior Member

    I don't know. I'll try to roll her and get back to you. The PANDORA, a SPRAY replica, was rolled and came back up with the masts gone. BERTIE has been through a great deal of bad weather and never came close. Most boats are stable when inverted, even with outside ballast. The modern racing sled with its flat sections and very wide stern seems to form a stable shape inverted. Having a very large chunk of heavy metal on the end of a fin keel certainly helps the recovery and BERTIE's ballast is all inside, so she does not have the ultimate righting force of a modern type, but can easily pack ten tons of brick or manure and deliver it on a tidal beach. Vessels are designed for different jobs.
     

  15. goodwilltoall
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    goodwilltoall Senior Member

    Bataan,

    Please give dimesions:
    SA
    Displacement
    Ballast
    Length
    Beam
    Draft
     
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