Jet flap control

Abstract

Abstract 1,174,496. Jet flaps on aerofoils. GIRAVIONS DORAND. 15 June, 1967 [20 June, 1966], No. 27652/67. Headings B7G and B7W. [Also in Division F2] A jet flap mounted on the trailing edge of an aerofoil 1 (e.g. an aircraft wing or a helicopter rotor blade) comprises a deflector flap 3 hinged about an axis 2 parallel and adjacent to an edge of a jet outlet, and a secondary flap 5, located in the path of the jet, and pivoting about the axis 2 to vary the cross-sectional area of the outlet, and to divide it into two apertures 6, 7. The secondary flap 5 may have its upper face curved about the axis 2 so that the aperture 6 remains constant, and always smaller than variable aperture 7. The two flaps 3, 5 may be moved together to vary the direction of the jet, and the flap 5 may be moved independently to vary the jet cross-sectional area. The flap 3 may comprise a second rigid part 9 pivoted at 10, and a flexible surface element 8 forming a flexible continuation of the upper surface of flap 3 and pivoted to the rear end of part 9. In a rotor blade the effective area of the nozzle may be increased along the trailing edge of an advancing blade and reduced on retreating blade, thereby providing additional propulsive thrust. The flaps may be moved in unison in the same direction in the manner of a vectored jet nozzle.

Inventors

• 👤 Pierre Rene Leon Bernar Dorand

Bibliographic Details