Greg Ketterman's 1983 California State Polytechnic University thesis "Design Modifications for a Model Hydrofoil Sailboat".
Analysis and mathematical model of a single-masted model of early Trifoiler concept. Includes velocity prediction program (VPP) source code in BASIC.
Used by permission from Greg Ketterman.
- Ketterman TriFoiler Thesis Inline version
- Media:Ketterman_thesis.pdf (I'm having trouble uploading this... stay tuned)
Narrative by Dan Ketterman that accompanied the polar diagram below as excerpted from email to User:Neuperg March 2006.
"This is my personal judgment of wind, boat speed, wind and boat angle to the wind, and wave conditions, myself, I weigh about 165 and my wife/crew, is about 130 lbs. These speeds are based on me driving. In looking at the polar diagram closer, my gut feeling is the boat speed is for a single pilot going to weather for both wind levels of 18-35 MPH. However, the diagram looks like it would support 2 people onboard for broadreaching in the wind range of 18-35 MPH. Therefore, I am saying that weight is less critical when sailing deep, because the center of gravity (CG) on a TriFoiler is aft upwind due to the drag in rigging, but the CG goes forward due to less rig drag aloft while broadreaching. More speed generates higher thrust vectors in a more forward direction."