Concept for an amphibious aircraft float/ski.
This is a rough approximation to the float configuration. There will be a wheel protruding from the float centered near the back of the two mini-wings. It will also have a tail wheel protruding through a tail ski like planing surface at the rear. A little better example can be seen at Waterbug Aircraft. The little wings just represent what is needed to support the aircraft when it is on-plane. They will be incorporated into the float/ski bottom because they would be a problem on rough ground or rough or deep snow. The bottom of these foils follow an equation for the shape which give minimum drag for a planing body. I found this NASA technical report TECHNICAL REPORT R-93 from 1961 in which they gave the equation and performed experiments which showed a large reduction in drag. I have noticed this shape on the tail of some new power boats. The center flat area of the ski will be covered with a replacable Ultra-high molecular weight plastic sheet as is used on snow ski bottoms and truck bed liners. There will be a suspension system allowing operation on rough terrain/snow as well as water. The first design will be for the light sport category with mountings for common existing aircraft.
I am working on modeling the float and aircraft dynamics with Blender 3D animation software which has the Bullet physics game engine incorporated. So far I have modeled a 1946 Aeronca Champ on regular landing gear, Federal 1500 skis and PK floats. I made them roll or slide down a ramp and go over some rough ground. I have written python scripts within the game to model the exact configurations of the spring/shock and wheel/ski rotation, including the front ski bungee and rotation limit cables. I added the ability to use the up and down arrows to increase and decrease engine thrust so that I could make the aircraft keep going until it falls of the end of the world ;^) I have yet to model water for the float plane or model aero lift and drag. I have made all of the control surfaces controllable, however, so that I can make a flight simulation later. Buoyancy modeling can be seen in the simplebuoy.blend file. Tie the buoyforce.py python script to an always sensor for the object to float. You should have a mesh which has no more than 2 faces per edge. I have tied it to the excellent plugin for waves found at www.ashsid.sk in the WaveBuoy.blend file.
This work is in support of my main ongoing project to design a plane I call the Waterbug , for the Light Sport category.
I recently found an old document on an aircraft I designed in 1982 called the Speedolight , for the Ultralight category.
