So what went wrong???

Discussion in 'Boat Design' started by ondarvr, May 19, 2014.

  1. Rastapop
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    Rastapop Naval Architect

    Yep, not trying to attack you, apologies if it sounded harsh at all! ;)
    Just adding more info to the picture.
     
  2. Milehog
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    Milehog Clever Quip

    Not taken that way. Just unsure if I came across clearly.
     
  3. Rastapop
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    Rastapop Naval Architect

    Down a slip of course.
     
  4. Richard Woods
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    Richard Woods Woods Designs

    I haven't spent much time on this thread, so may have missed something. The stability report was written nearly a year ago. I assume much of the interior work was done since then. I'm sure others will agree that weights are always more than one hopes, and CofG always higher.

    Most large boats/ships that are slipway launched (eg Titanic) are not finished, usually just an empty undecked shell.

    Both the Wooden Boat and Trawler forums have (different) posters who have the most up to date news

    Richard Woods
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    Judging by the air rushing out of the stern quarter, she was filling with water, and the bow was quite high when she went over.
     
  6. SamSam
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    SamSam Senior Member

    Or that was the carriage tires blowing out. That far into the launch there wouldn't seem to be much weight on them, but some ramps are bad with dropoffs or maybe rebar or something sticking out to slash a tire. I don't know if it's their own private ramp, or how much it's used. Someone might have dropped something down there taking their boat out in the middle of the night and just moseyed on home without telling anyone.
     
  7. Michael Y
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    Michael Y Junior Member

    A boat that looks like this one fairly challenges you to believe it will be stable in the upright position. For that reason alone, I'd have hoped that its stability calcs would have received above the norm scrutiny. To paraphrase the old saying, extraordinary claims of stability requiring extraordinary proof.
     
  8. Rastapop
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    Rastapop Naval Architect

    Northern Marine has issued a press statement:

    On Sunday, May 18, 2014, New World Yacht Builders LLC (DBA Northern Marine) suffered a major accident during the launch of its new 90’ expedition yacht, as the yacht capsized onto its port side during the launch and settled to the bottom of the launch area. Fortunately, the experienced master and crew responded to the peril professionally and all aboard escaped, with only two employees suffering minor cuts. There was no property damage to the surrounding launch area and potential environmental contamination was negated as a result of instant response to avoid possible fuel leakage, of which there was none.
    Since the casualty, there has been much speculation as to what happened, often with little or no supporting evidence. Northern Marine is cooperating with the United States Coast Guard in its investigation into incident.
    Northern Marine has launch more than 35 vessels, ranging from 57 to 151 foot motor yachts, with all of its trawler models having been launched using transport dollies at the same ramp where the accident occurred on the 18th. Northern Marine continues to have complete confidence in its trawler designs, all of which have been tank tested and passed the same United States Coast Guard (USCG) stability standards applied to commercial fishing vessels operating in the North Pacific. Northern Marine trawlers have safely sailed to destinations throughout world, such as the 75-foot Starship that successfully completed a 1000 day, 78,000 mile journey to explore parts the world rarely seen by mankind.
    Northern Marine believes the 90 foot yacht involved in the launch accident to be no exception. Since the accident, the project naval architect/Professional Engineer has confirmed that the yacht, as designed, had adequate stability with the amount of ballast aboard at the time of launch, provided that “severe heeling moments” were not induced during the launch. Unfortunately, it appears that just such a severe heeling moment did occur during the launch. While investigations as to the cause of the capsizing are continuing, the physical evidence on, and adjacent to, the launch ramp suggests that the dolly carrying the weight of the port stern of the yacht may have suddenly dropped off the edge of the boat ramp during the launch, causing the vessel to experience a sudden list to port from which it could not recover in its light condition for launch.
    As noted above, the official USCG investigation continues and Northern Marine will cooperate in those investigations to their conclusion. Northern Marine is also working closely with the yacht’s purchaser and their insurance underwriters to address the losses resulting from the accident.
    Northern Marine wishes to express its heartfelt appreciation for its many employees that contributed their talents to the construction of the yacht
     
  9. SamSam
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    SamSam Senior Member

    The boat looked pretty centered on the ramp when it tipped over, how could it
    ?

    Once they had it tipped upright by the crane and all the water out, why didn't they let it loose to float by itself, since
    ?
     
  10. SamSam
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    SamSam Senior Member

  11. SamSam
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    SamSam Senior Member

  12. Rurudyne
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    Rurudyne Senior Member

    The comment about people not trusting the boat in the future (in SamSam's link) seems plausible. I wonder how they will try to address that? For example, there have been plenty of comments in just this thread that she didn't "look" like she should be very stable to begin with ... so might any correction be one which addressed the appearance of an issue as well as the substance of any actual issues?

    (actually, the whole psychological thing could make sense of the motive for that modified Wyoming thread, the OP just doesn't fully "trust" the design as is and so wants to outright modify it ... does that sound about right?)
     
  13. Rastapop
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    Rastapop Naval Architect

    Sounds like it wasn't fully ballasted, and the ballast on board wasn't enough to handle a mishap like this.

    Sits at the door of the NA who calculated the amount of ballast needed for launch, methinks.
     
  14. nzboy
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    nzboy Senior Member

    I have spent a little more time and got these lines plans as close to hull 8501 Baden as is possible Its pictured at 2 metres draft .The meta centre is 3.148m at 2m draught 135ton. meta centre rises to 3.4m at1.6m draft 85ton.From photos I believe she was launched at this weight so was very possible her cog was over 11ft so yes she was top heavy . nm3 6.jpg

    nm3_Linesplan.jpg
     

  15. Skyak
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    Skyak Senior Member

    Nice job! Can you check it bow high stern down? Even when the boat was free of the trailer the bow didn't get to design waterline and the stern was well below.
     
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