I thought the moment when it transitioned from sailing like a regular boat to almost-flying as a surface-skimming hydrofoil would be more … momentous. I’ve been on my share of boats, including large ferries, small sailboats, and plenty of others in between, but never been on a hydrofoil and I was curious what flying along the water might feel like during the brief ride from the Brooklyn Marina out toward Governors Island on the East River in New York. It didn’t feel like flying, but it was a bit like a riding in a sports car.
Traditional boats of this size — about 30 feet — start to bounce and slap the water as they gain speed. But on a hydrofoil, that’s when the foils start to do their work. On the surface, the VS-9 looks like plenty of other catamarans.
But under the hull are two wing-like structures that lift the boat as they slice through the water. Computer-controlled underwater flaps keep the ride smooth and stable. In the VS-9, most of the lifting is done by the front foil, with about 20% handled by the rear.
The rear foil also hosts the electric motor, which Vessev makes in-house. Laakmann said that it’s important to keep costs in line — eventually, you’ll have to bring production in house, so why not do it earlier in development? The only thing Vessev doesn’t build are the batteries.
By lifting the hull clear of the water, hydrofoils can operate more efficiently than other boats. That’s especially important for electric boats, where every kilowatt-hour counts. Shipbuilders have been experimenting with hydrofoils for well over a century.
The design offers several advantages, including lower drag and a smoother ride. The subtle transition I experienced on the VS-9, from sailing to almost-flying, underlined just how smooth a hydrofoil can be. Despite hydrofoils’ advantages, they’re not a panacea.
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