Ocean rowing boat stability calculations

Discussion in 'Stability' started by Tom Robinson, Sep 22, 2020.

  1. Tom Robinson
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    Tom Robinson Junior Member

    And I’ve read Eric’s fantastic article on the design process for Jacob’s boat. Very informative.
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    It is generally the case that friction drag is the main resistance (neglecting wind, of course) at low speed, so any extra surface area is not advantageous, and especially, I would think, if the general shape is near identical, as it would be with lapstrake as opposed to carvel on the same frames. On the other hand, clinker might offer some roll damping benefit.
     
    Last edited: Sep 23, 2020
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    Tom, there was a bloke come ashore on Stradbroke Island after a cross-pacific row, maybe 15 years ago, (another mad pom I think ! :D) do you have any info on him, his boat, and the story of his journey ? Have there actually been any west-to-east crossings ?
     
  4. Tom Robinson
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    Tom Robinson Junior Member

    Thanks for the info about friction resistance. The amount of added surface area from the laps would be very small indeed. 9mm laps 24 feet long, about 8 under the water, I can’t see that making a huge difference?


    That was jim shekhdar. I’ve read his book. He rowed in a plywood ‘woodvale pair’ design, very common.

    A few people have rowed across the Pacific East to West. Most want to go non-stop which does not interest me. I’ll hopefully be stopping off at a few islands along the way. Who would want to row past Tahiti and not go ashore for a beer and a hike?
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    Stopping at those islands may require sophisticated information processing of currents and winds to vector you on to the spot. They are tiny targets. I doubt Shekdar wanted to come ashore at straddy !
     
  6. Tom Robinson
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    Tom Robinson Junior Member

    It has been done before in the Pacific, not easy but doable. I think Jim was just happy to arrive in Australia. Stradbroke is a lovely place anyway...
     
  7. Mr Efficiency
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    Mr Efficiency Senior Member

    He did finish up landing in a reasonably heavy surf, not sure the boat negotiated it successfully, but he did.
     
  8. latestarter
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    latestarter Senior Member


  9. Eric Sponberg
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    Eric Sponberg Senior Member

    Tom Robinson,
    I have just stumbled across this thread. Good luck on your rowboat design. I am still here in Australia, up in Townsville, QLD, at the Townsville Yacht Club.
    The COVID-19 pandemic has put a hold on our cruising for the time being. I'll be here for a few months yet. If you would like some first-hand insights to the design of ocean rowboats, feel free to shoot me an email: eric@ericwsponberg.com.
    Cheers, Eric
     
    bajansailor likes this.
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