Deep V to Cat like Hull

Discussion in 'Boat Design' started by majorm, May 7, 2012.

  1. majorm
    Joined: Apr 2012
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    majorm Junior Member

    I was curious if anyone has made a hybrid of a deep V front part of the hull with a catamaran type rear. By that I mean have it flatten or raise up slightly in the center at say 2/3 the way back and seperate the hull into two pieces where the running gear would be. I found a patent that i think does what im talking about but id like to see something actually made like that to see if there is anything obvious why its a bad idea. If your interested in the patent here is the link. I bought the PDF of it so i can see the other pictures but im thinking unless this is an outrigger type hull this is what im thinking about.

    So what do yall think about this and do you know of any boats that were made like this? The whole idea i had was it would handle rough water and have a little more stability in rocking. The catamaran style dual hull look in the back would lower resistance to make it a more efficent boat in my theory. So really all your doing is maybe making the hull a little wider and notching out the center rear third approximatly.

    ETA: I recieved the patent paper in my e-mail last night and was able to see all the pictures now. It seems his design is a little different than what I had in mind but was similar. What i was thinking you would have a normal yet wider version of a deep V hull. Then once the CG and main plaining area was established then make the hull concave and end with two hulls. So visually from the side it would look like a normal V hull yet from the rear you would see the two pieces with the concave center. The issue though is how the displacement will change and how to get some of it back.
    Last edited: May 8, 2012
  2. rwatson
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    rwatson Senior Member

  3. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    This is a "monomaran" that looks like a vee-hull from from ahead, but a tunnel hull looking from behind ? I did make a 20 footer like that years ago, unfortunately don't have any pix at hand. It was around 40 degree deadrise at the forefoot and round 18 degrees right aft. Rode wonderfully well, very good through chop, and characteristically did not show the tendency to get airborne of either a tunnel or conventional vee hull. It was however no more efficient or inefficient. The snag was it would not track properly in beam seas, or more particularly if they were a little behind beam. No fix was found for this tiresome characteristic, I think I understand the physics of why it was happening, but could not eliminate it to my satisfaction. Maybe I can draw a pic of what it looked like, it is not a new idea, few things are !
  4. rwatson
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    rwatson Senior Member

    Cousteau used this design to demonstrate the commercial viability of the sailing system - many commercial cargoes are not meant to list more than ~10 degrees.

    Efficiency was a secondary consideration

  5. Cheesy
    Joined: Aug 2008
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    Cheesy Senior Member

    Just a quick note, you dont have to buy patents, there are various patent to pdf websites that are free, google might even export them as a pdf
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