Abstract: A pivotal strake located at the nose section of an aircraft forebody. The strake pivots about an axis that is essentially perpendicular to the surface of the nose section. Rotation of the strake will influence the forebody vortices to create a resulting yawing moment on the aircraft. The rotating strake can be used to provide directional control of an aircraft, even at high angles of attack.

Abstract: Methods and apparatus for stability and maneuver control using rotatable nose strakes to control forebody vortices at medium to high angles of attack are disclosed. In one form, small left and right nose strakes are supported on a member or members forming the forward most contours of the forebody. Supporting of the two strakes on a single member allows rotation of the two in unison, the angular position thereof controlling the asymmetry of the forebody vortices at higher angles of attack, while support of each strake on a separate forebody nose member allows individual strake control for the same purpose. In another embodiment, the strakes may be mounted on a nose boom for rotation about the axis of the nose boom, whereby rotation of the strakes about the nose boom axis affects the development of the forebody vortices and the asymmetry thereof. Various embodiments and methods of operation thereof are disclosed.

Abstract: A method of extending the maneuver, performance and flight safety of a specific fighter aircraft, namely, the F-16, is disclosed. In accordance with the method, a portion of the forebody strakes on the original aircraft which extend along each side of the fuselage to the front of the cockpit are eliminated, with a small leading edge cap capping the leading edge just forward of the structural bulkhead at the aft end of the cockpit. While the method involves the removal and replacement of skin panels, access doors and various frame members adjacent the cockpit, as well as the rerouting of one or more wire bundles, no major structural changes are required, and the modification may be made utilizing ordinary maintenance and repair procedures. The net result of the modification is to shift the center of pressure which acts on the forebody aft, thereby eliminating the deep stall characteristics of the aircraft.