Model TriFoiler

By Greg Ketterman

The TriFoiler project really began with this model in 1981. It was inspired by boats like Crossbow and Sidd Shutt's hydrofoil triamaran. It started out as a desire to break the world speed record for sailboats. Notice how big the foils were.
This was typical - I would start out big and find out they work better small like this;
For my senior project in school I decided to write a Velocity Prediction Program (VPP), redesign the model based on the VPP, make changes to the model and test the model to verify the VPP. It was a very ambitious project. The VPP predicted that much smaller foils would go faster and it would not tip over with a much bigger sail. The main question put to the VPP was; if the weather foil pulls down to increase stability, would the increase in power make up for the increase in drag. The answer was yes, so I made the sail 2 times bigger and the foils about 1/2 the size. I also went to the L shaped foils and the whole amas pitched. I also painted it white as shown here;