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Tunnel - Stern - Designs

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  • liokai2002
    Hello, I´m new in this group and please excuse me talking of things you have read and discussed already several times. I found the site of Atkin & Co. at
    Message 1 of 4 , Nov 28, 2004
      Hello, I´m new in this group and please excuse me talking of things
      you have read and discussed already several times.
      I found the site of Atkin & Co. at DUCKWORKS and was stirred up by
      the TUNNEL - STERN designs, especially by Sand Piper a "Shoal Water
      Day Cruiser". What struck me most was the reverse - V tunnel stern.
      From tank tests at Duisburg University and a tank in Berlin I know
      that underwater shapes similiar to Sand Piper are hydrodynamically
      the most effective - not only in shallow waters. Boats with these
      shapes are faster, need less fuel an have more course stability in
      waves ( safer, RO-ROs with Bulb Bows need rudder corrections by
      computer every 20 seconds) . This is the result of tests and
      development work from a friend over a span of 25 years. He started
      with Sail- and Motor Boats and now develops RO - RO Carriers of 450
      ft. The shapes are of course not the s a m e, but they are s i m i l
      i a r.
      From this I´m very interested in any literature about the Tunnel -
      Stern Designs ( esp. Sand Piper ). I´ve read already all the early
      postings about Tunnel - Stern Designs an will continue my research
      about the work of William Atkin who found out this effective shape so
      early as 1922 !!!! I´m hoping for a bit help. Regards, Manfred
    • ronschwiesow
      ... so early as 1922 !!!! I´m hoping for a bit of help. Regards, Manfred This is helpful reference to additional support for the efficiency of Atkin s hull
      Message 2 of 4 , Dec 3, 2004
        --- In AtkinBoats@yahoogroups.com, "liokai2002" <manfred.pech@w...>
        wrote:
        > What struck me most was the reverse-V tunnel stern.
        > From tank tests at Duisburg University and a tank in Berlin I know
        > that underwater shapes similiar to Sand Piper are hydrodynamically
        > the most effective - not only in shallow waters. Boats with these
        > shapes are faster, need less fuel an have more course stability in
        > waves (safer, RO-ROs with Bulb Bows need rudder corrections by
        > computer every 20 seconds). This is the result of tests and
        > development work from a friend over a span of 25 years. He started
        > with Sail- and Motor Boats and now develops RO - RO Carriers of 450
        > ft. The shapes are of course not the same, but they are similiar.
        > From this I´m very interested in any literature about the Tunnel-
        > Stern Designs (esp. Sand Piper). I´ve read already all the early
        > postings about Tunnel-Stern Designs an will continue my research
        > about the work of William Atkin who found out this effective shape
        so early as 1922 !!!! I´m hoping for a bit of help. Regards,
        Manfred

        This is helpful reference to additional support for the efficiency of
        Atkin's hull design. If you haven't yet seen it you might enjoy
        looking at information on the Atkin Rescue Minor that Robb White
        built and tested. See
        http://www.messingaboutinboats.com/archives/mbissueaugust02.html.
        Also Dave Gerr has at least one design with a similar hull; see
        http://www.gerrmarine.com/images/boat_images/power/gerr42tunnel/gerr42
        tunnelD.GIF
        The Higgins boats also used the reverse vee stern, although it is a
        little hard to determine that from available pictures. See
        http://www.higginsmemorial.com/design.asp and
        http://www.higginsboat.org/html/photo/phot012.html

        I am particularly interested in a cruiser for 2, intermediate in size
        between Atkin's Rescue Minor and his River Belle. Intended speed is
        slower than the designed maximum for either of these designs. I'm not
        sure how the tunnel-stern, V-bottom Seabright Skiff hull form
        performs at low speed, but Robb White's observations are encouraging.
        Ron
      • liokai2002
        Hello Ron and Rob thank you both very much for your kind help and support to understand more of Atkins SAND PIPER hull design. I would like to put some fotos
        Message 3 of 4 , Dec 7, 2004
          Hello Ron and Rob thank you both very much for your kind help and
          support to understand more of Atkins SAND PIPER hull design. I would
          like to put some fotos of "Maderform" hulls (RO-ROs) and University
          papers into the files, but have difficulies with my Windows messenger
          since I've changed my Internet provider to DSL and am not able to
          extinguish the old server adress. But I hope to overcome my
          difficulties soon.
          As I understand the Links from you Ron, the genius William Atkin
          designed SAND PIPER and Mr. Higgins from Higgins Industries adepted
          it and modified it to EUREKA and then to a landing craft that helped
          to free us from Nazi Terrorism in Europe. Or are EUREKA and the
          LANDING boat Higgins own designs without the influence of the Atkins ?

          The "Maderform" hulls in Germany started in the seventies from the
          idea that the underside of an aircraft wing (too) gives aerodynamic
          lift. From this the underside (in water) of a boat has to have a
          similiar shape. But this was only a first step. Hundreds of tests
          have been made and boats and ships have been built with increasing
          successful results. As one can see from the University tests and the
          Mathematics with NAVIER - STOKES formula there is a certain amount of
          lift from the special underwater shape to counteract the sucction
          (Bernoulli) of other (convex) boat shapes and a very smooth waterflow
          and a very low wake behind the boats and ships. I do not know whether
          the designer of the "Maderform" hulls has ever seen the SAND PIPER
          drawings or Mr. Higgins Landing boats. But I would like to ask him
          next time I meet him.

          I don`t know whether the SAND PIPER has ever been tested in a Tank
          test. But it is my strong opinion that this design will show a lot of
          advantages over current boats. It is a pity that there is not known
          enough to get proved results and to give this designs the recognition
          and honor it deserves. Thank you for your help. Regards, Manfred
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