Power to tow vs. power to propel

Discussion in 'Boat Design' started by misanthropicexplore, Jan 10, 2022.

  1. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Interesting and fun thread, here's the YouTube,

     
  2. Tiny Turnip
    Joined: Mar 2008
    Posts: 865
    Likes: 274, Points: 63, Legacy Rep: 743
    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    Thanks for that - best explanation of the soliton video I've seen.
     
  3. misanthropicexplore
    Joined: Apr 2018
    Posts: 82
    Likes: 14, Points: 8
    Location: Upper middle Missouri River

    misanthropicexplore Junior Member

    'they could tow their maximum load of 22 tons at 10 mph even with a single horse'

    I was actually reading about that last night, trying to find some solid references on any of this, and it turns out that it was a very unique circumstance due to towing in very narrow, very shallow water ways to create a standing wave at speeds/loads where it wouldn't normally happen.
     
  4. Tiny Turnip
    Joined: Mar 2008
    Posts: 865
    Likes: 274, Points: 63, Legacy Rep: 743
    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    As explained in the linked pdf, and the video portacruise shared. Its not actually a standing wave at all, its a soliton.
     
    misanthropicexplore likes this.
  5. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Apparently, a soliton wave travels faster in deep water and slower in shallow water, (like a tsunami) and presumably drags the boat along with it for a sustained ride, as much as the slip allows, haha. Maybe the 10 mph speed would have been even faster and out of range for the horse to pull, if the channel had been deep? Tsunamis referenced in the video can travel over 500 mph with several hundred miles between their diminished, barely noticeable, crests!
     
    Last edited: Jan 12, 2022
  6. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member


    I like it! Maybe only a heavy duty shark or surf fishing rod &reel would be enough to crank the kayak forward, assuming that the pull is 10 x more effective, haha! Cast out, with a surf anchor like weight, crank in, repeat as needed! Easy thing to test out? So long as you can turn the crank and the anchor holds, you should move forward! There are also electric power reels that are used for deep sea bottom fishing, if your hand gets tired....
     
    Last edited: Jan 12, 2022
    misanthropicexplore likes this.
  7. gonzo
    Joined: Aug 2002
    Posts: 16,809
    Likes: 1,722, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    That is a variation on kedging. A traditional technique to move ships.
     
    portacruise likes this.
  8. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Trivia on casting a fishing line- the records are around 300 yards/ m with a 5 Oz weight and a very long 17'? rod, but they do make very long telescopic surf rods, haha. Not sure how an arrow with a fishing line drag would compare.
     
  9. gonzo
    Joined: Aug 2002
    Posts: 16,809
    Likes: 1,722, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    Think big. How about a whale harpoon cannon?
     
  10. DogCavalry
    Joined: Sep 2019
    Posts: 3,093
    Likes: 1,578, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

    Oh yeah. A set of them, some launching, some kedging.
     
  11. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Yeah, your kedging concept appears to work, whether large or small!
    But the OP asked about kayaks... and sometimes, for some people, less is more, haha!

    TapamTheMovie http://tapamthemovie.com/trailer.html

    Ps. Just an example, I have no connection with the video authors or any of the equipment.
     
    Last edited: Jan 13, 2022
  12. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Some idea that is trivial and obsolete is not necessarily stupid or unuseful! It might be unattractive to the big boys because it is not profitable or cannot be proprietarily protected, JMHO. That may not affect the DIY tinkerer that is trying to solve issues that may not have come up before.

    For the small boat people, I did some tinkering at the River Rapids yesterday. The fishing rod idea seems to work pretty well pulling me against a current. The key is to let a stiff rod do the work when you pull, and the reel is used mostly to take up the slack. If precise control is needed, it may be an issue in some types of Rapids or opposing fast water. I did not address the issues of long-distance throws required, or the secure self anchoring and release of the fishing weight which would be required.

    Cheers!
     
  13. DogCavalry
    Joined: Sep 2019
    Posts: 3,093
    Likes: 1,578, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

    That is legitimate engineering research right there!
     
    Last edited: Jan 14, 2022
  14. portacruise
    Joined: Jun 2009
    Posts: 1,476
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member


  15. fredrosse
    Joined: Jan 2005
    Posts: 439
    Likes: 81, Points: 38, Legacy Rep: 56
    Location: Philadelphia PA

    fredrosse USACE Steam

    "Not sure how an arrow with a fishing line drag would compare."

    With respect to line casting vs using an archer's bow to get the sea anchor far ahead of the boat: The relevant issue here is the energy that is effectively used to throw the sea anchor (and its line) forward. The bow involves about 80 pounds of pull through about 2 feet length, or 160 ft-pounds of energy. Casting a line, with a big fishing pole, how much energy is that? I don't know, because I always get my energy from steam, but many here can probably give an opinion about how much energy one can get by casting.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.