145 results about "Sonic boom" patented technology

A method for integrating an engine nacelle below the wing of a supersonic aircraft with low sonic boom capabilities includes determining the shape of a reflexed portion of the airfoil on the underside of the wing, and a corresponding shape for the upper surface of the nacelle to provide favorable interaction between the wing and the nacelle. In some configurations, the reflex and/or the nacelle are shaped to maintain positive pressure under the reflexed portion of the wing, to the trailing edge of the wing. A gull dihedral wing is designed to form a partial shroud around the nacelle. Such configurations reduce drag at the trailing edge of the wing, and the force of the positive pressure on the gull dihedral wing portion provides additional lift that partially offsets drag from the nacelle.

A wing for use on a supersonic aircraft that includes an inboard section a central section of the wing outboard of the inboard portion, and an outboard section. The outboard section can be a winglet oriented anhedrally relative to a lateral axis of the supersonic aircraft. Leading edge segments on the inboard section, central section and outboard winglet may have mounted thereon leading-edge flaps. These flaps are adjusted by a control system operable to reposition the leading-edge flaps in order to improve the aerodynamic performance of the supersonic aircraft. This winglet promotes sonic boom minimization. Further, the wing tip anhedral allows greater inboard dihedral. This effectively pushes lift aft for sonic boom and control purposes while minimizing the movement of control surfaces.

Objectives to be achieved by this invention are the provision of a method for determining the ultimate fuselage shape of supersonic aircraft by integral modification of the upper and lower surface shapes of the fuselage, to reduce sonic boom without increasing wave drag, as well as the provision of such a fuselage front section shape. A method for determining the fuselage shape of an aircraft for supersonic flight of this invention employs different methods of determining the fuselage lower-surface shape and the fuselage upper-surface shape, whose upper and lower boundary is defined for each fuselage cross-section by the horizontal line including two points at which the fuselage width from the bilateral symmetry plane is maximum. The above fuselage lower-surface shape is determined by optimization of an objective function to minimize the pressure increase amount of the sonic boom pressure waveform on the ground, estimated using a panel method and waveform parameter method; the fuselage upper-surface shape is determined by optimization of an objective function so as to minimize drag, estimated using a panel method.