Rough, working notes from tinkering with small flat bottomed electric boats.
Hydroplaning and hydrofoiling speed
It sounds like 10 knot wind is sufficient to plane, and this usually means a board speed of 7 knots. (From https://www.reddit.com/r/windsurfing/comments/2q5z4p/minimum_speed_for_planing).
It's a bit unclear what speed is needed to foil. Still need to experiment more.
Hydrofoils are commonly used in many flat bottomed small boat sports: surfing, windsurfing, kitesurfing, efoiling.
The setup involves a short and wide board designed for planing, with a special port in the back. The port is sturdy and supports a mast which juts vertically downward. At the tip of the mast is a wingset, including a fuselage, wings and a tail stabilizer.
Seems like beginners start with a short mast. Kits come with a 55cm mast. Short masts are easier to start with but harder to maneuver.
There are various ways of mounting the mast to the board. Most commonly, something called a Tuttle or Deep Tuttle is used. See also Tuttle Box Confusion on foils (angry but informative)