GB866608A - Improvements in or relating to aircraft - Google Patents

Abstract

866,608. Controlling aircraft. POWER JETS (RESEARCH & DEVELOPMENT) Ltd. Sept. 9, 1959 [Sept. 18, 1958], No. 29911/58. Class 4. An aircraft comprises a pair of wings having lift control means for varying the lift produced by the wings extending along the trailing edge of each wing, and a control for varying the setting of the lift control means, the wings being cambered with the maximum camber substantially at the mid-chord point of the wings and the neutral point of the aircraft being to the rear of the mid-chord point. The wing 2 has a chord line 41, along which is positioned the mid-chord point O of the chord C and the neutral point N of the aircraft, and a camber line 42 so arranged that the point of -maximum camber coincides with the mid-chord point 0 with the point N always aft of point 0, preferably at 55%C. The aircraft centre of gravity is approximately positional at point O, and though they may be vertically displaced, G will never be aft of N. The camber line 42 may be a circular arc or a parabolic arc. The trailing edge of the wing carries a flap 5 associated with jet propulsion nozzles in the manner disclosed in Specification 787,012 and 823,591, the flaps being controlled for simultaneous movement in the same or opposite directions by mechanism as disclosed in Specification 790,193 and 823,591 in order to deflect the jets. Consequently the lift on the wings, which are set at zero incidence in flight, is composed of a component LF resulting from the jet flap effect and a component LC resulting from wing camber, both components acting at the mid-chord point O. The invention may be applied to a cambered wing 50, Fig. 8, with conventional trailing edge flaps 51 in place of the jet flap arrangement of Fig. 6, though such wing should preferably be provided with nozzles for blowing air out or sucking air in over the upper surface of the flaps for bounding layer control in known manner. An arrangement is described, Fig. 7 (not shown), for a retractable or extension flaps and apparatus such as disclosed in Specification 823,591 is described for actuating the elevators for control during supersonic flight. Specifications 758,269 and 829,753 also are referred to.