GB712023A - Aircraft with variable sweep wings - Google Patents

Abstract

712,023. Controlling swept-wing aircraft. ARMSTRONG WHITWORTH AIRCRAFT, Ltd., Sir W. G. Dec. 4, 1952 [Dec, 7, 1951], No. 28691/51. Class 4 In an aircraft in which the wings are angularly adjustable during flight for sweep, the wing roots have arcuate tracks coacting with respective arcuate guides within and fast with the fuselage,' whereby each wing can be swung about a substantially vertical axis which is spaced outwardly of the fuselage, on the same side as the wing, and in such a position that there will be no change in the stability and trim of the aircraft during the angular adjustment of the wings, there being a reversible power-operated means, acting substantially tangentially of the tracks, for adjusting the sweep of both wings simultaneously. Each wing, of which the top surface 22 and leading and trailing edges 24, 26 are shown in figure 1 in relation to the fuselage 20, is closed at its root end by a bulkhead 34 formed on its top and bottom edges with two tracks 36 which are arcuate about a vertical axis X. Each pair of upper and lower tracks cooperate with channel guides 50, 52 rigidly attached to a beam 54 within the fuselage. The beams support a fore and aft bulkhead 56 to each side of which is attached a guideway 67 for a nut 64 mounted on a screwed shaft 62 rotated by an hydraulic motor 69. The nut is pivotally attached to the inner end of a rod 66 attached at its outer end 68 to the bulkhead 34 in the wing root. Should excessive wing deflection during an adjusting movement cause the tracks 36 to bind in the guides 50, 52 a relief mechanism shown in figure 5 is brought into automatic operation. In this arrangement, the bulkhead 34 is omitted, the tracks and guides being shown at 36a, 50a and a spanwise cantilever beam 72 is positioned within the root end of the wing fast with the fuselage with its outer end 74 resting on a piston movable within a cylinder 82. If, during a sweep, the hydraulic circuit to the motor 69 becomes overloaded an automatic cut-off valve diverts the liquid to the cylinder 82 which reacts against the piston and the beam 72 to reduce the wing deflection and remove the binding action between the tracks and guides. To prevent downward deflection of the wing during this operation from overloading the tracks in the opposite sense, an arm 94, pivoted at 108 to the beam 72 and in contact at its outer end 96 with the upper surface 22, of the wing is arranged to operate a cut-off valve 92 located on the sweep axis X.