Boat Capsize Evidence

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

  1. Tim B
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    Tim B Senior Member

    The clip you're reffering to ( http://www.youtube.com/watch?v=AFY9x5YBft8&feature=related ) is just an example of Newton's first law. ie. That which moves will continue to move until something gives it a good reason not to.

    The fact the the seat that you were lounging on stopped isn't considered a good reason.

    The driver (I refuse to use the word helmsman for this idiot) purposefully throttled back hard, which would induce a dive. I see no unapparent reason for the chain of events which follwed, nor any issue of design. Boats don't just dive underwater because they feel like it. There is ALWAYS a reason. Whether it's apparent to you is a matter of technical knowledge and experience. Both of which I would question for small fast craft.

    I'm not into protecting idiots. If you fail to follow advice, then you have only yourself to blame, not the person giving the advice.

    Tim B.
     
  2. troy2000
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    troy2000 Senior Member

    What is this nonsense about "no good reason"?!? There were perfectly good reasons. You're carrying on like they were jaunting across a mirror-smooth surface, and the boat, all on its own, suddenly submarined. You might as well rail about the fatal design flaw that allows a car to hit a tree; how dare auto makers not design a car that won't leave the road if you turn the steering wheel the wrong way, or that won't spin its tires if you give it too much gas on ice, or that won't roll over if you take a sharp curve at 70 mph instead of the posted 35?

    I think it would probably be close to impossible to put enough flare in the bow of that boat to prevent it from doing what it did, unless you threw out any other consideration of function and appearance. Ya think?
     
  3. Loveofsea
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    Loveofsea New Member

    apex, i stand by my safety record. I've been towed 3 times in 90,000nm. Twice because of a failure in a brand new engine, the other because of a lower unti failure (75nm out of port--i was back out there with a new L/U the next weekend :cool: . I've traveled the equivelent of circumnavigating the planet between towings :D You?

    and if i am such a poor boat designer then why has my plywood boat design lasted 18 years, year around, outlived 5 outboards, and traveled 65,000nm of open seas and the hull has only degraded less than 1%? I suppose you know of a lot of similar wooden powerboats running around out there, right?

    Forgive for making this brazen statement, but it would be virtually impossible to use the materials i used and build a stronger and more durable vessel than this one. I have worked around aircraft all of my life and i designed this skiff using the principles of aircraft structure design rather than traditional boatbuilding design.

    >>>as few pieces as possible---every piece being as large as it can possibly be<<<
     
  4. apex1

    apex1 Guest

    You´re quite off topic mate! All the time!

    I was´nt ever in tow with a ship or yacht. I know how to maintain my stuff.

    Lousy seamanship and biased opinions about boatdesign, thats your problem.
     
  5. troy2000
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    troy2000 Senior Member

    I'm bowing out, folks; have fun. This is another thread being powered by someone's obsessions....
     
  6. souljour2000
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    souljour2000 Senior Member

    Hate to state the obvious but Apex is right...this kind of arrogance is what gets you killed... this guy sounds like Capt Quint from "Jaws"...he survived the "Indianapolis" only to get eaten by a transient fish....
     
  7. Loveofsea
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    Loveofsea New Member

    Two last (rhetorical) questions:

    Would a Boston Whaler or a Grady or a Fountain, etc even be capable of submersing the bow on relative flat seas?

    ....Why not?


    PS: souljour, arrogance doesn't get you killed. It's inexperience, stupidity and sheer bad luck that will do you in.

    Thank you for the spirited exchange gentlemen!

    Brad

    (loves the sea)
     
  8. TeddyDiver
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    TeddyDiver Gollywobbler

    And the winner of the Loveofsea's design contest is here!!! No more submerged bows! No more capsizing! It may have a couple of other disadvantages but no game no gain..:p
     

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  9. SamSam
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    SamSam Senior Member

    When submarining is done on purpose it wouldn't seem to be a design flaw. My understanding is to do it as it's done in the posted videos, when up to speed you throw the boat into reverse (jet drive only I would imagine) which pitches the boat stern high and bow low, but the forward momentum allows the bow to submarine. (I think the first submarining was a failed power turn, that's why the guy threw up his hands and the woman wasn't all that happy) If the boat submarines with the only thing being done is suddenly throttling back, that would seem to be a poor attribute to me. If your motor quits at speed, you automatically submarine? If a boat has a tendency to stuff itself into waves that would be a definite disadvantage also, at least to me. Here's the last few posts on a thread about submarining....

    http://www.moomba.com/msgboard/showthread.php?t=5831

    When you're doing nothing, and 3-4 waves come in over the bow from nothing other than passing boats, what is that- a design flaw or poor design or just a design compromise?

    I'm not sure the major cause of capsizing (sinking?) is water coming in over the transom, but it does happen. A few years back we had someone drown when the boat stopped so someone could light a smoke and the wake came over the transom and sunk them.

    .
     
  10. Sheepy
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    Sheepy Junior Member

    I'm curious as to why they don't put excessive flare on these boats? My guess would be to stop the bow acting sorta like an airplane wing at speed towing a skier?
     
  11. powerabout
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    powerabout Senior Member

    I always thought 'shipping a greeny' as we called it over the bow was a design feature as where we skiied in OZ was damn hot.

    What goes up must come down, when boat racing just make sure the launch was good so when you come down you are in the correct attitude or else...
    A bit like ski jumping...its pretty hard to recover in the air
     
  12. powerabout
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    powerabout Senior Member

    at 58kph
    I dont even think a tiger moth will take off
     
  13. gunship
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    gunship Senior Member

    i think a tiger moth will JUST about take off :p but the point stands.

    so compare:
    [​IMG]

    with:
    [​IMG]
     
  14. Sheepy
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    Sheepy Junior Member

    No, however a boat at speed may flip over?
     

  15. powerabout
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    powerabout Senior Member

    Ok, Here's one at take off
     

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