What is a Hydrofoil?

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At rest, a hydrofoil lies in the water like a normal ship, but once it starts moving, the body of the ship or the hull rises up and the vessel is supported on its underwater wings called foils. Hydrofoils are used mostly as ferries making short and fast trips. In an ordinary ship, much of the engine power is wasted in overcoming the drag of water around the ship's hull.

A hydrofoil solves this problem by lifting the ship right out of water. The water wings lift the hull as the ship gathers speed. As the water's friction gets less, the ship shoots ahead.

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