Flotation pod angle

Discussion in 'Hydrodynamics and Aerodynamics' started by Leif Weisner, Jun 18, 2020.

  1. Leif Weisner
    Joined: Jun 2020
    Posts: 1
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    Location: Alaska

    Leif Weisner New Member

    Hello all,
    I have a 18 foot by 72”wide Jon boat with a semi v. It has a tunnel and a jet foot. The motor is a 115 four stroke and weighs down the back quite a bit. I had the welder put on flotation pods and they are angled down slightly maybe a degree or two at most. All the welders I have talked to seem to say that the flotation pods should come out straight and essentially be an extension of the hull. However when you look up pre fabed pods they always say to angle them up. Wondering if anybody had any insight. I can grab pictures tomorrow.
  2. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    Might be possible to get some opinions with pictures shown, but seeing these pods are now fitted, can you test it to see what the difference now is ?
  3. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    On OB pods, some are angled up or stepped and angled in order to improve shallow water performance. They allow boats to get on a plane with several inches less prop draft. Often, they are set up so that if the hull doesn't bottom out when transitioning to a plane, the props won't hit. These type often run dry when on plane. On a shallow file-bottom jon, I'd just run it flush and give due consideration for steering with a jet foot in a tunnel. Hopefully it sticks out a bit. Angling the pods down can adversely affect high speed handling, contribute to porpoising, and generally degrade the boats dynamic stability. I'd expect you can get in the low forties with a decent jet, and that is plenty fast to worry about the stability issues that might crop up.
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