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(2)

suction effect on the upper surface of the plane to much larger angles than fifteen degrees, the slotted plane was devised.
   In its simplest form it consists of a narrow slot extended transversely across the plane in the direction of the span. It has a wide opening on the under surface connected to a narrow exit in the upper surface of the plane. The exit is controlled by a hinged flap extending all along the leading edge of the air foil section and is controlled manually from the pilot's cockpit.
   This operates by introducing a new live air stream to the upper surface of the plane and prevents the burbling state. It also allows a suction effect on the upper surface of the plane to continue to a larger angle than before with a consequent higher maximum lift plane. The performance of this air foil had been to effect landing pseed that is much lower with a given wing area than we have been ordinarily obtaining with the conventional air foil.
   The slot arrangement is mechanically controlled from the pilot's cockpit by control of a hinged, counter-leading edge surface of air foil section which controls the width and extent of the slot opening at the will of the pilot.
   It is practically impossible to get a good ratio of lift

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