• 9th October 2006 - By greg

    I got an email the other day from Anthony Davis with an idea that I thought could have some merit. So, I decided to model it up quickly to see what it would look like.

    Human Powered Semi-submersible

    The idea is that the boat would be mostly submerged with the water line almost as high as the deck. The rounded top would be the only part of the boat that would be above the water line. A clear dome covers the pedalling station which would be completely water tight. Fresh air would have to be pumped into the boat from a snorkel or something.

    I based the concept model from the existing model of Concept1, but I think it would be better to design a rounded hull (more submarine-like) than something that is more kayak shaped like what is shown.


    1. Drastically reduced windage. The low, aerodynamic profile is far less likely to be pushed backward while moving into a head wind.

    2. Stability. This bottom heavy design would be fairly stable and almost impossible to capsize. Also breaking waves would be less likely to push the boat over, sink it or capsize it.

    3. Dry. The pilot should be able to pedal during very rough ocean conditions because the sealed capsule will keep every thing dry. Breaking waves will simply wash over the curved canopy dome.


    1. Reduced windage. The aerodynamic profile would also mean that the boat is less likely to be pushed forward with following winds.

    2. Heat. If the canopy top is not meant to open, it could get very hot in there.

    3. Safety. If the is even the smallest leak, there would be no way to get the water out. Even if the front and rear compartments were water tight to prevent sinking, if the pedalling compartment were to fill up with water, it couldn’t be drained with scuppers because it is lower than the water line.

    4. This concept is so low in the water, that there would be no way of opening the top to get fresh air, or to climb out and stand on top.

    5. If the fresh air pump or vents were to malfunction, and the canopy top can’t be opened, the occupant could suffocate!

    There are probably too many cons for this concept to be considered safe for an ocean crossing. I think the existing idea behind my current design – Concept1 takes the pros of this idea and eliminates the cons. It’s smooth, aerodynamic and covered for less drag through headwinds, and a dry cockpit during rough seas. Plus it’s high enough above the water line to allow the canopy top to be opened during calm conditions, or to get out onto the top.

    Concept 1 with the canopy top down

    Concept 1 with the canopy top open. (Boy that water line still looks pretty high. I can see that the slightest wave would easily flood the cockpit. hmmm….

  • One Response to “Thinking outside the box – the human powered semi-sub”

    • stewart on September 28, 2011

      Try the lower hull shape with conning tower to sit in and then the top of the conning tower could be opened with out risk of sinking. Cheers Stewart

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