Airboat design

Discussion in 'Boat Design' started by RB1, Nov 3, 2010.

  1. RB1
    Joined: Nov 2010
    Posts: 3
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Glasgow, Scotland

    RB1 Naval Arch. student

    Hi,
    I'm a student currently in second year naval architecture and marine engineering. We have to come up with and airboat design as a group project, which will be vacuum formed from a thermoplastic material, and then the models will eventually be raced. Would be interested to know if anyone has any tips on a good hull design for an airboat?
     
  2. Leo Lazauskas
    Joined: Jan 2002
    Posts: 2,696
    Likes: 151, Points: 63, Legacy Rep: 2229
    Location: Adelaide, South Australia

    Leo Lazauskas Senior Member

    It would be helpful if you give us some details.
    What are the limits on the dimensions?
    How long and far must the model travel under its own power?
     
  3. RB1
    Joined: Nov 2010
    Posts: 3
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Glasgow, Scotland

    RB1 Naval Arch. student

    Max. Hull Dimensions:-
    250 mm x 100 mm x 28 mm (this includes the 3 mm thick top deck plate)
    "Task 4: Fit out the hull with a motor and fan (supplied) and battery pack (supplied), ballast and trim as required to reach the design draught.
    Foam and Balsa will be available to build a platform for the motor and fan. The fan is a three blade 127mm Dia. prop directly driven by a small electric motor (Remember this is an air fan and has to be clear of the water and deck).
    For the more adventurous there will be brass rod, piano wire and thin Balsa available to manufacture rudders, steering surfaces or other additions you think will improve the performance or aesthetics of the vessel."

    Not sure exactly how far it has to go, but just really looking for general inspiration on hull shapes...
     
  4. Submarine Tom

    Submarine Tom Previous Member

    Try Google and SEARCH option on this forum.

    Post pics of your progress and hurdles, you'll get lots of "input".

    -Tom
     
  5. messabout
    Joined: Jan 2006
    Posts: 3,272
    Likes: 411, Points: 83, Legacy Rep: 1279
    Location: Lakeland Fl USA

    messabout Senior Member

    There have been model airboats on the market for many years. Some are gas powered, some are electric. Search a few of the hobby model web sites. In the US you could try Tower Hobbies which is one of the larger suppliers.
     
  6. WickedGood

    WickedGood Guest

    A lots of Rednecks run Airboats down in FLA and Lousiana in the swamps.

    Every one that I have seen weather it is Plywood, Alum or Glass all are about 10-12 ft wide and 20-24 ft long flat bottom with a angled bow.

    allows you to run over Logs & critters without hurting the boat.


    Polular engines were old VW Bug engines ( Those are German Made and not very good but cheap in the junk yard) and Lycoming and they are made by Textron ( Same folks that bring you such fine products as the CG47 and the Predator Unmanned Drone to eliminate Moslum Terroists to protect Freedom.


    [​IMG]
     
  7. PlaningWheel
    Joined: Nov 2010
    Posts: 78
    Likes: 2, Points: 0, Legacy Rep: 5
    Location: Canada

    PlaningWheel Junior Member

    Air Boat Design

    I have a posting on this site concerning an amphibious boat and a website:
    http://www.coldgold.rotoquad.com
    Click 4 wheel drive boat.

    I also has a passive system driven by an air prop that would win your contest.
    However the patent application is not completed but I will make the plans available (for your purpose) with a NDA.

    Let me know through my website if your interested.
     
  8. RB1
    Joined: Nov 2010
    Posts: 3
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Glasgow, Scotland

    RB1 Naval Arch. student

    @PlaningWheel - Love the 4 wheel drive boat! Think it's genius! Would be interested to see your air prop system when all the patenting's completed.

    We have more or less completed out airboat model, and unfortunately we have no choice in terms of propulsion systems as we are all supplied with the same stuff. Have gone with a fairly standard flat-bottomed thing which should be quite fast and stable, but I suspect it will be a bit of a pain to steer.
    Thanks for all the help folks.
     
  9. PlaningWheel
    Joined: Nov 2010
    Posts: 78
    Likes: 2, Points: 0, Legacy Rep: 5
    Location: Canada

    PlaningWheel Junior Member

  10. MAPAHaus
    Joined: Feb 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Duluth, GA

    MAPAHaus Junior Member

    RC Airboat Hull design

    Hi, I am new to airboats. I got the Aquacraft Alligator Tours Airboat and found that it is very easy to flip. I found out from other users of the same airboat that it is because the hull is designed too narrow. So I added a total of 4 inches to make it wider and was able to solved the flipping issue. But, a new issue came out. The boat turns and hook at high speed. Any thoughts you guys. I can't go straight at hight speed with it making and sharp u-turn... I would appreciate any help from anyone. Thanks a bunch.
     
  11. CaptBill
    Joined: Jan 2010
    Posts: 184
    Likes: 10, Points: 0, Legacy Rep: 64
    Location: Savannah,Ga

    CaptBill CaptBill

    You might have your motor out of trim horizontally and it is driving the bow, making it dig in. Maybe rake it back slightly (the top edge), so the bow wants to lift and not dive.

    Just a thought.
     
  12. MAPAHaus
    Joined: Feb 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Duluth, GA

    MAPAHaus Junior Member

  13. Village_Idiot
    Joined: Oct 2007
    Posts: 382
    Likes: 17, Points: 18, Legacy Rep: 138
    Location: USA

    Village_Idiot Senior Member

    Were your additions completely equal on both sides? A little extra on one side might make a pretty big difference in friction torque to one side. Does the boat tend to want to turn to one side? At all speeds or just high speeds? Try adding some shims to the engine/prop mount to trim back/forth and test differences (carefully!).
     
  14. MAPAHaus
    Joined: Feb 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Duluth, GA

    MAPAHaus Junior Member

    @Village_Idiot:

    The additions are pretty equal on both sides. Maybe I will sand it up to make sure that they are totally equal. They are just made of 2" thick rigid insulation board, so they are easy to trim out. However the boat turns to both sides, at times right and at times to the left. Where ever the wind or the slight wave on the water pushes the boat I guess. But atleast I know that it's not just leaning to one side.
     

  15. MAPAHaus
    Joined: Feb 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Duluth, GA

    MAPAHaus Junior Member

    @Village_Idiot:

    By the way, it only turns at high speed. If I run it at idle it is going to the direction that I want the boat to go.
     
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.