3 ms·

There are already hydrofoil sailboats - is that what you mean? https://en.m.wikipedia.org/wiki/Sailing_hydrofoil https://en.m.wikipedia.org/wiki/Sailing_hydrof

• dragonwriter 3y ago
  Hydrofoils don't lift entirely out of the water.
• yread 3y ago
  I think they mean like flying as in not touching the ground/water. Sounds doable: these speeds are usually ground speeds so the applied wind speed (ground speed+wind speed) could reach 100kmh which is enough for a sail plane.
  • DelaneyM 3y ago
    As other replies have mentioned, you need to push against the water to position the windfoil to produce thrust. Otherwise you're just being pushed by air, and you're limited by windspeed. Sailboats can go many times the speed of the wind they're in.
• clort 3y ago
  No, ground effect is (AFAIK) when the depth of the wing (fore-aft) is greater than the distance above the surface it is flying over. The leading edge of the wing creates a pressure wave that reflects back from the surface and provides lift to the whole wing. You can see it with birds like pelicans which skim the water for a long way without needing to flap at all. I don't know if this would enhance the speed at all though, there are presumably other effects involved with going faster.