Hello dear Sycho 15,
About the Tri-Foiler, a study was carried out in the MIT Water Tunnel ( with a depressurized free surface ) in 1994 by C.Savineau and J. Paschkewitz on a model of the hydrofoil used on the Ketterman's boat.
The section was far from optimum, as simple NACA 2410, and cavitates beyond 37 kt for low Clift. Like 20% chord bubble for 39 kt, 60% at 45 kt and 100% ( supercavitation ) at 55 kt.
Take a look at the remarkable web site of T. SPEER.
When you seek for ultimate design for subcavitating sections, you "hit the wall" like "sound barrier" around 52 to 54 kt without swept back wings, even with ultra-thinned sections...beyond it's supercavitation which reigns...
Friendly Yours,
FRENCHIE
