Airboat design

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?

 

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?

 

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...

 

Try Google and SEARCH option on this forum.

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

-Tom

 

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.

 

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.

 

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.

 

@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.

 

Hi RB1

Here's the design I was offering for your air boat project:
http://www.waterwheel.rotoquad.com/diskboat.html

 

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.

 

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.

 

CaptBill...The boat seems to lift up properly though. See the youtube video here..

http://www.youtube.com/watch?v=YztsWNER3Gk

 

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!).

 

@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.

 

@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.