Old Question by New Guy

[SGMoyers]

Where can I find information about the shape and design of a proper hull for a mini airboat? I am interested in also learning about different types and materials that have been used. I am thinking that if just a flat bottom were good enough there would be more air prop powered Jon boats, that would be too easy!

Thank you for any information or ideas you may give me.
Steve

[eskimoboy]

Welcome Steve, correct me if im wrong but its usually POWER TO WEIGHT RATIO. If your talking smaller Hp then you need a lighter hull. In my quest for a perfect airboat(Reliable,low fuel consumption and enough power to carry a buddy and refreshments) I think I have found that perfect hull for me. I have an airboat thats powered by an 084 military surplus engine rated at approx. 45hp that sits in a 230lb fiberglass hull. This hull is really light and strong and has held together really well for me.I drive in all conditions from -25 degrees celcius on snow and ice to + 30 on salt water and in rocky rivers. My current top speed in deep water is 35 MPH, using a 1.9 - 1 v belt reduction swinging a 68 inch 3 blade ivo prop. I live in Eastern Canada and im running at sea level. This hull I purchased from Chuck at Airboat Pros.
You can check out some of my videos on youtube with headings starting with: nicks 084 mini airboat

Nick

[Papee]

I'm not sure how I can sum that up in a short answer other than it is that easy, the best bottom for an airboat is a flat one or relatively flat. A Jon boat is not flat, it has ribs and do not make a good airboat hull. That along with there are not really any around that are wide enough.

The size of your hull and material really depends on your running conditions. A more severe condition most often requires a aluminum hull. If you are building a ride boat length is not a big deal but if you want to fish out of it a longer boat will be better for 2 people. Width is another thing, a hull that is too wide will slow the boat due to more wet area contacting the water on plane or drag. If you keep your boat in the water your hull does not have to be as wide, a wider hull will help spread the weight over a larger area when trying to run dry.

The very minimal width for a bottom in my opinion is 5ft and that is what I run because I stay in the water. I run a boat that has no turning chines which are a bit harder to operate than a boat with them. A chine is a curved area at each side of the bottom. In my opinion you can go too wide with a mini airboat hull.The surface area is good to help float the boat higher in the water but that same area can hinder the boat when on plane with a small power plant. The hull and motor are very important when designing your boat. A wider boat will be more stable if you need a higher seating arrangement also.

Now on to the rake of the front of the boat, a longer slope will help in rougher water but takes away from the floatation of the boat at drift. A sharper slope or rake give you more floatation when drifting. It all depends on your use. As far as the sides, they should be at least 18" but could be a bit shorter if weight is a concern. So, I hope this helps, there is not really a hull that covers everyone's needs.

[SGMoyers]

Thanks all this is some really good information. I live in southwest Georgia on Seminole Lake. Lots of swampy areas with water plants, submerged trees/stumps and a big boulders when you least expect them. Most of the air boats here are aluminum with ploy sheeting on the bottom. And of course are powered by big block V8's.

I understand that this will most likely be trail and error as I go along. On limited funds I am hoping to avoid as much error as possible.

Thanks again.