Amazon river, Loadum up

Discussion in 'Boat Design' started by Ravencry, Mar 16, 2009.

  1. ancient kayaker
    Joined: Aug 2006
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    Location: Alliston, Ontario, Canada

    ancient kayaker aka Terry Haines

    An even number in each row would make it easier to balance the boat laterally. Other than that, whichever layout gives you the most boatlike looking boat! When designing, bear in mind local practice and preferences. The kind of seat spacing on an airliner might not be too popular with a nursing mother hauling a couple of chickens to market. There may be more to this than speed and fuel consumption, like ease of anchoring/boarding etc. Also there's the ability to spot and dodge debris in the water; as The Fonz would say, leaping the shark or in your case maybe a curious freshwater dolphin.
     
  2. Boston

    Boston Previous Member

    speaking of which
    I know the Gangies River dolphin went the way of the Dodo
    do you ever see any amazon river dolphins
    B
     
  3. Ravencry
    Joined: Mar 2009
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    Ravencry Junior Member

    IMG_7234.JPG
    This is sort of what I had in Mind. Its about 26ft long and about 7feet wide.
     
  4. TeddyDiver
    Joined: Dec 2007
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    TeddyDiver Gollywobbler

    6 rows of two even better.. anyway if you wan't economy you need a narrow long boat... being still able to turn it around back to home.
     
  5. Paulo
    Joined: Apr 2003
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    Paulo Junior Member

    Why not indeed build a catamaran?!?

    I was wondering why not consider a catamaran. A catamaran could have the DWBeam of each hull as low as 600mm the DWL with 8000mm and a draght of 350mm. The loaden displacement would be 2000kg. Given that you carry 12 people (= 900kg) and the boat weight beeing as much as 450kg, you would still have about 650kg of cargo! Sounds like a hell of a little boat. The great advantage of a catamaran is that a little 60hp outboard would be able to drive it nicely through the water.

    Bons Ventos,
    Paulo
     
  6. Boston

    Boston Previous Member

    sounds kinda wide and there's a lot of crap to miss in that river
    check out the logs floating downstream in those first few pictures
    B
     
  7. Paulo
    Joined: Apr 2003
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    Paulo Junior Member

    Catamaran for the amazon river

    Hi Boston,

    I have seen the picture with the logs and other floating debris. I have been to the amazon and the rio negro, both in Brazil. Although the picture show a vast amount of debris, I must say these tend to be concentrated in "belts" around and along turbulant areas on the river. It is not the whole river covered with the logs shown in that picture.

    Having sad that, I believe that the ideal craft would be a catamaran with 2 engines, one behind each hull and therefore protected be each hull too. As the hulls are very thin and with moderate draght, I believe most of the logs would be throughn to the sides rather then underneath the hull, thus passing either side the engines.

    In the case of a single engine installation, the risk of impact by passing debris would pose a more significant problem. However I think a very short hull type of fixture for the engine would do the same job.

    My case for the catamaran is that the engine power required to drive the boat is much less then the power required to take a monohull out of water and into plane. Furthermore, the catamaran offers much greater lateral stability, which is a greatly appreciated caracteristic. As the boat is loaded and the boat sinks gradually into the water, the DWBeam does not change, thus the resistance due to wave formation does not change.

    anyway, just a couple of ideas: food for thought.
    Bons Ventos,
    Paulo
     
  8. Boston

    Boston Previous Member

    cat is definitely stable and two engines better than one
    so ya if you can miss all the debris with a wide hull form then it even offers more deck space and load handling
    best B
     
  9. apex1

    apex1 Guest

    Sorry mates, but a Cat is the worse choice for a violent river. And common sense tells easily why.

    Regards
    Richard
     
  10. Boston

    Boston Previous Member

    righting factor is non existent
     
  11. TeddyDiver
    Joined: Dec 2007
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    TeddyDiver Gollywobbler

    There's one exception concerning cats and rivers.
    Two hulls with much narrower gap btw the hulls than traditionally in cats lift water in the gap much higher and thus makes it possible to install the prop (small outboard engine) btw the hulls and the prop can be higher than any other installation. This makes possible to drive in water so shallow that the hulls are in light contact with the bottom. Not very efficient way to drive normally but a "dry season" mode. Worst drawbacks are need of other engine to get some speed and limited speed range bcs too low speed lower the water level by the prop and too high speed floods the hulls..
    And of course.. it's a bit dangerous :D
     
  12. M-Sasha

    M-Sasha Guest

    Can you imagine to hit a log with one hull only? That to happen in a rapid (to make the scenario thrilling). Manoeuvring in weed must be very interesting too.
    I am shure the list is longer, come on apex, you know the Amazon, tell us your scruples.

    Sasha
     
  13. Hägar

    Hägar Previous Member

    Yes I can imagine that. i would go for a "narrow boat" of about 9 - 10 mtrs. and a Yamaha or Suzuki 90 hp outboard. They do 16 -18 kn, are stable, rigid and easy to repair.
    The hovercraft idea was not so bad either.
     
  14. Ravencry
    Joined: Mar 2009
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    Location: Iquitos

    Ravencry Junior Member


  15. apex1

    apex1 Guest

    The most important points were maid clear already.

    Ravencry
    , apart from the fact that it´s fully enclosed, that looks like the boat you need, yes. But can you get some plans of that to build it yourself?

    Regards
    Richard
     
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