The end result is foil which works well and is easy to learn on not very fast but fast enough.

How fast is a hydrofoil. Lift One side of the boat can be raised out of the water by altering the hydrofoils enabling sharp turns. A hydrofoil is completely unlike a floating hull because as the speed approaches zero the drag of the hull goes to zero but the drag from supporting the entire weight with a hydrofoil goes to infinity. Completely counterintuitive I know.

At low speeds the hull body of ship sits in the water and the hydrofoils are totally submerged in the water. Beyond these speeds increasing amounts of cavitation should be expected until a supercavitating state is eventually reached. Speed Hydrofoils can enable speeds of up to 100kph three times that of the wind.

But the drag also goes up when the hydrofoil goes very fast. Towing behind a boat or jetski in the open. Hydrofoils are a way to side-step that problem by lifting the ship and minimizing wake-formation.

A Cross section of a flapping hydrofoil showing forces during upstroke and downstroke. At the end of the fin youll notice what looks almost like a little model airplane attached. In general hydrofoils can be designed to operate at speeds of up to around 5060 knots without incurring the significant effects of cavitation although some will be present.

But theres another way to get a feel for a hydrofoil before taking it into the surf if you have the means. A hydrofoil board is basically a surfboard with a hydrofoil attached to the bottom. That is the basic design of a hydrofoil board.

Hi Raiders Ive got hydrofoils on my outboard which are like wings on either side of the cavitation plate im looking at taking them off and running the boat without them to see how it goes. Because it produces lift L on the upper surface during the downstroke and the lower surface on the upstroke the hydrofoil is uncambered. At very high speeds 60 mph that wave-making resistance becomes insanely strong.