Displacement versus planing

Discussion in 'Boat Design' started by kapnD, Jan 8, 2022.

  1. kapnD
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    kapnD Senior Member

    I thought this might clarify things a bit! 91F8909F-59C1-4C74-A0B1-A3068F5E0DE9.jpeg
     
  2. messabout
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    messabout Senior Member

  3. Will Gilmore
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    Will Gilmore Senior Member

    That osprey nest really seems to be moving.

    What do you suppose Hull Speed is on those deer?
     
  4. Andrew Kirk
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    Andrew Kirk Pedal boater.

    Hull speed? I estimate their length at 2.2 meters so the square root is 1.483 X 2.8 gives 4.15 mph. Of course a clever deer could use it's snout like a wave piercing bow so this figure may not be the whole truth. ;)
     
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  5. fallguy
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    fallguy Senior Member

    Is it just me or is that six bucks?
     
  6. mc_rash
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    mc_rash Junior Member

    Since the deers in displacement-mode are submerged till their neck the waterline is the length of the neck which may be something around 30 cm. The hull speed for this Lwl is ca. 1.33 kn.

    Take two deers next to each other connected with beams and you'll get a SWATH.
     
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  7. fallguy
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    fallguy Senior Member

    ...and the fun ended
     
  8. mc_rash
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    mc_rash Junior Member

    Actually I'm not a native english speaker and I'm sorry I didn't understand the six bucks joke, @fallguy maybe you want to explain it to me? :D
     
  9. fallguy
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    fallguy Senior Member

    all is well, I am only afraid someone will correct your fun; perhaps now not
     
  10. fredrosse
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    fredrosse USACE Steam

    I notice one of them at least has his port side running light, I wonder if he has a green one on starboard?
     
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  11. Barry
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    Barry Senior Member

    looks like the front one has his port light hung off his nose, nah! couldn't be, wrong type of deer
     
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  12. Will Gilmore
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    Will Gilmore Senior Member

    Lead-Syroco-real.jpg
    It does look like that Ospray is going for the speed record. Probably name something like the Nest IV. Just as long as it keeps periodic contact with the water, it might count.

    -Will
     
  13. kapnD
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    kapnD Senior Member

    The English language is a curious thing, a buck is a male deer, but also a slang word for a $1 bill.
    It can also mean to go against something, as to buck the current.
     
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  14. portacruise
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    portacruise Senior Member

    Is the 5th one running on a sandbar?
     

  15. fallguy
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    fallguy Senior Member

    The 5th one is a planing deer.
     
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