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The Flexible Hydrofoil Wing Float(Fhwf)is a new device for lifting the headline of a trawl.It is made fromSuperior Grade canvas.Part of the structure is cut away at the leading edge to form a water intake.The flow ofseawater inflates the canvas into a shape similar to that of an aircraft wing,thus generating lift.Sea trials havebeen conducted on practical wing floats suitable for full scale fishing gear.Model tests have been conducted in awind tunnel.At low attack angles,the lift coefficient(C_L)is 0.32,the lift to drag ratio(G_L/C_d)is 5 and the mo-ment ccefficient(C(?))is positive Better results are obtained when netting is placed below the model float,comparedwith the float in isolation.The wing float has many advantages compared with conventional lifting devices.It maybe used at any depth.Large net mouth openings may be achieved at high speeds.It is cheap,simple to install andto handle.Spare wing floats may be folded for storage and do not require much space.
The Flexible Hydrofoil Wing Float (Fhwf) is a new device for lifting the headline of a trawl. It is made from Superior Grade canvas. Part of the structure is cut away at the leading edge to form a water intake. The flow of seaawater inflates the canvas to a shape similar to that of an aircraft wing, thus generating lift. Sea trials have been conducted on practical wing floats suitable for full scale fishing gear. Model tests have been conducted in awind tunnel. At low attack angles, the lift coefficient (C_L) is 0.32, the lift to drag ratio (G_L / C_d) is 5 and the mo-ment ccefficient (C (?)) is positive Better results are when netting is placed below the model float, comparedwith the float in isolation. The wing float has many advantages compared with conventional lifting devices.It maybe used at any depth .Large net mouth openings may be achieved at high speeds.It is cheap, simple to install andto handle. Spare wing floats may be folded for storage and do not require much space