Boat Capsize Evidence

Discussion in 'Stability' started by Sachi, Oct 10, 2009.

  1. Loveofsea
    Joined: Jan 2007
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    Location: Southern California

    Loveofsea New Member

  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Why do you not believe the reality of the "stuffing" a boat stunt? Do you honestly think perfectly good boats just suddenly nose dive? What kind of idiot are you? You're constantly making comments about things that plainly aren't true, as if you knew something different, yet you haven't the understanding of the design concepts or principles to back up your repeated attempts at retort.

    I gave this thread up a couple of pages ago and here you are still ranting about what you don't understand. Now, it's my mission to point out how stupid you are. We don't need your level of "experience" and frankly it's dangerous to others.

    Comments like this make it very clear that your capacity to understand reasonable explanations is beyond your ability. Maybe you should go back to sucking your mash potatoes through your straw and pinching at the night nurse when she's on her rounds.

    Just because you don't like it or don't understand it, doesn't mean it's not happening commonly or with a reasonable level of safety (I can preform this stunt repeatedly, all day long with no damage). It just means you're too stupid to pay attention to the video or others that have experienced just what the video shows. This level of arrogance needs to be weeded from the gene pool.
     
  3. Sheepy
    Joined: Apr 2009
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    Location: Aus

    Sheepy Junior Member

    @ someone who knows could you please tell me the reason for not having excessive flare on these boats? I would genuinely like to know if I have it right.
     
  4. powerabout
    Joined: Nov 2007
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    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    Flare does not stop a nose dive/submarining
    If you ship a greeny at idle ( and dont know how to avoid that)you need more freeboard for the conditions.
    I'm no NA but have raced powerboats and spent thousands of hours in ski boats so here's my laymans explanation...


    If the boat is pointing down hill it will go downhill till the bouyancy of the hull starts to apply a force greater then the momentum
    As the deck is usually flat it then opposes coming back to the surface ( assuming its under)
    The hull having a fine entry is the path of less resistance so helps it to go down.

    Once the drag and added bouyancy overcomes the mass/momentum you slow (maybe almost to a stop) and float back to the surface. Its all dynamic so any combo of the above happens.

    These are all variables so you can have no problem if the angle of incidence is low, or have a bit decelaration, and the bow lifts back or add more speed and the problem get worse etc etc, this problem on race boats has injured and killed many people and snapped hulls in half.
    ( from 100mph to stop in a boat length will hurt)

    Newtons law...


    A wave piercer is just as dangerous IF IF it changes its running attitude and points downhill.
    The Ozzies here might remember a commercial 40+m wave piercing cat that went in on Port Phillip Bay ( Melbourne ) in the 80's.
    It was steaming at normal cruise but in swell and it nose dived at 30kts or whatever speed it was doing, nearly went vertical and submerged the passenger area by more than 80%, yes the fish were looking at the passengers in the aquarium, it then popped back up.
    Many broken arms and legs. ( I had a customer who happened to be on board who described it to me)


    Oh...a stunt trick to do....Jet skiiers have been doing it for years and ski boat drivers also for that instant cool on a hot day...
    The same can be done to stand a boat almost vertical off a wave without fear of going over backwards
     
  5. Loveofsea
    Joined: Jan 2007
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    Loveofsea New Member

    Properly designed boats do not suddenly dive below the surface throwing kids into the water-PERIOD! The vast majority of boats are designed to keep people INSIDE the boat. The ones that throw people out of the boat are not safe.
     
  6. souljour2000
    Joined: Aug 2009
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    Location: SW Florida

    souljour2000 Senior Member

    People get ejected from boats all the time...not as much as from cars or maybe bars...but still quite often...remember...as the comedian Ron White says...you can't fix stupid...btw..I wish there was a retired career Coast Guard guy or gal in this forum who could really weigh in on this and similar threads with some stats and even some scary but educational stories maybe...
     
  7. apex1

    apex1 Guest



    Replace "PAR" with your name and you will find hundreds of supporters here!..:cool:
     
  8. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Awww.... that's nothing. I can launch a boat in a much shorter distance.



    Loveofsea, I wouldn't discard some of the advice from these respected boaties because it doesn't fit your reference window.
    Nothing is always as it seems ok. Instead of taking these guys on, learn from them.
     
  9. Loveofsea
    Joined: Jan 2007
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    Loveofsea New Member

    Hello Fanie~ I'm a 'boatie' also. The difference is, i spend a lot more time actually boating than i do talking about it. I was looking thru my log books the other day and i estimate that i have spent the equivelent of 250 24 hour days with a tiller in my hand--in open seas :)

    i keep wondering why it is acceptable for those hulls to suddenly dive below the surface, yet there is no way on earth anyone would tolerate that flaw in a grady or a whaler--none of the local experts have been able to answer that.

    all i get are insults, name calling and the typical sock-puppet drive-by from the likes of apex :rolleyes: .


    Souljour, people get ejected for all kinds of reasons--virtually all of then due to extraordinary circunmstances, not because the bow suddenly decides to take a dive below the surface. Again, a properly designed hull would not be able to do that no matter what the driver did-PERIOD.


    Why is it acceptable in one boat and not in another :confused:
     
  10. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    There may be a difference in spending lots of time on the water - and actually design a boat :idea:

    I suspect that boat diving under the water was done so deliberately by the skipper. Look where the engine (and most of the dead weight) is located. All he had to do was trim the nose down some and turn the boat so it can cut under the water. It is the center of gravity that keeps him upright.
     
  11. Loveofsea
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    Loveofsea New Member

    Fanie, i designed and built my boat :D .

    Could the skipper of a grady or a whaler do that?

    Why not?
     
  12. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Okay, you designed and built a boat, but you've not answered the one question I directed at you, which was, why do the majority of pleasure boats have the bow they do, which you've described as inherently unsafe? So Mr. designer of boats, why? It's one of the most common features on modern pleasure craft and shared by most commercial power craft (sailboats too) as well. I can make a Whaler dive like the video shows too. It will not be quite as spectacular, but it will dive and ship it's bow wave. The fact that you are too arrogant to accept things you don't understand is a good indication of what you're about. Just because you don't understand it, doesn't mean it's bad, it just means you don't understand it.
     
  13. apex1

    apex1 Guest

    The sock puppet builds boats since more than 30 years, holds a commercial master unlimited, and circumnavigated 3 times. (on motoryachts)

    Amateur..........there is a typo in your nickname, should read Lovesofa!
     
  14. troy2000
    Joined: Nov 2009
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    troy2000 Senior Member

    Jeez, is this thread still going?:(

    I don't know why you guys won't shut up and listen to loveofsea. After all, he designed and built his own boat, and hasn't sunk it (yet). So that means he must know more than all you wannabes who do it for a living....:rolleyes:
     

  15. Loveofsea
    Joined: Jan 2007
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    Loveofsea New Member

    I'm appaled, appaled i tell you :p That the state of commercial boat design has sunk to this level where a boat can suddenly dive below the surface and it's not considered unsafe :confused: Where is the oversight?? If Ford or GM put out a vehicle that did the equivalent, there would be a forced recall.

    Way back in '91 when i needed a serious offshore skiff, i had no faith in the industry. I can't tell you how glad i am that i didn't cop out and buy a conventional design.

    apex, it must have been fun to travel around the world 3 times. I bet you have a lot of incredible memories...
     
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