The internal structure of noun phrases in the Scandinavian languages

A hydrofoil for watercraft provided with air exit apertures at the under pressure regions of the hydrofoil and extending at least partially over the foil span. Ducts are provided internally of the foil and operatively connected with the apertures to which air can be admitted for the purpose of influencing lift. The front part of the hydrofoil profile possesses an upwardly cambered mean line for producing lift, whereas the rear part of the profile has the maximum profile thickness and a slightly downwardly cambered mean line without intersecting or cutting the chord line for producing approximately equal under pressure at the upper and lower profile sides. The air exit apertures are arranged at the upper and lower profile side at the region of the underpressure produced by the rear part of the profile.