577,958. Fluid-pressure motor control systems. JACKSON, A. R. May 3, 1943, No. 6953. [Class 135] [Also in Group XXXIII] An aircraft is sustained by sets of autorotative wings, each wing of a set being cyclically oscillated about an axis transverse of the aircraft as the wing rotates bodily about a main axis central of the set and also transverse of the aircraft. The amplitude of the oscillation and the mean position of a wing with respect to the oscillation which respectively determine the ratio of the speed of rotation of the wings about the main axis to the speed of the aircraft and the angle of incidence of a wing with respect to its actual path through space may be adjustable. The phase of the oscillation may also be varied. The aircraft shown is provided with screw propellers 2 disposed above the fuselage 1, and sets of autorotative wings 3 diverging laterally from carriers 10 each rotatable about a transverse axis which is inclined upwardly to give a stabilising effect. As shown diagrammatically in Fig. 8, the wings 3 are secured to pinions 11 rotatable about eccentric axes b on a carrier 10 rotatable about an axis a. The pinions 11 are geared through idlers 13 also rotatable about eccentric axes c in the carrier 10, to a stationary sun pinion 12 the axis of which is eccentric to the axis. a. The pinions are of equal diameter or that if they were respectively concentric with the axes a, b, c, the wings would remain parallel to the position shown at the 2 o'clock and 6 o'clock positions when the carrier 10 is rotated but with the eccentric mounting, the wings oscillate about their axes b as shown. To permit adjustment of the eccentricity of the pinion and also of the mean position of the wings with respect to the angle of oscillation b the mechanism shown in Fig. 9 is provided. The carrier 10 is rotatable in a bearing member 14. The sun pinion 12 is rotatable by a sleeve 24 on an eccentric sleeve 19 rotatable on a rotatable shaft 18 which is eccentric to a spindle 15 concentric with the axis a of the carrier. The sleeve 19 and the spindle 15 are respectively integral with sun pinions 12b, 12a. The idler 13 is similarly rotatable on an eccentric sleeve 21 rotatable on an eccentric sleeve 20 respectively integral with idlers 13b, 13a, mounted on a spindle 16 and the pinion 11 is similarly rotatable on eccentric sleeves 23, 22 integral with pinions 11b, 11a. The pinion 11 is keyed to a boss 36 on the wing shaft 17 which is rotatable on a spindle 35. The pinions are all of the same diameter and the eccentrics all have the same eccentricity. Levers 27, 28, 29 are secured to the shaft 18, and sleeves 19, 24, respectively. Thus by adjustment of the lever 27 the shaft 18 and sleeves 20, 22 are equally adjusted and by lever 28, the sleeves 19, 21, 23 are equally adjusted. With the radius of eccentricity of the several pairs of eccentric sleeves and shaft 18, arranged in opposite directions as shown, the pinions will all be concentric with their spindles and the angular position of the wings with respect to their axes b will hot vary as the carrier rotates., By equal adjustment of the levers 27, 28 in opposite directions, a desired degree of eccentricity may be given to the pinions and thus a corresponding amplitude of oscillation to the wings. The direction of travel of the aircraft is from right to left in Fig. 8 which effects rotation of the wings about the axis a in the direction shown. The direction of the radius of eccentricity is also normally as shown in Fig. 8 but may be varied by the levers 27, 28 to vary the phase. In order that the wings may have an angle of incidence with respect to this actual path through space to produce the necessary lift, the pinions 12, 13, 11 are simultaneously turned without affecting this eccentricity, by operation of the lever 29, the mean position of each wing with respect to its angle of oscillation being thus adjusted. By increasing the amplitude of the oscillation the speed of rotation of the wings for a given aircraft speed and thus the lift with a given angle of incidence is increased. By reducing the amplitude of oscillation to zero the wings assume a stationary position with respect to the aircraft and thus act as fixed wings. Control of the aircraft may be effected wholly by the wings, a turn being effected by first increasing the drag factor of the wings on the inner side of the curve and then by increasing the lift factor on the outer side to bank the aircraft. The drag factor is increased by altering the direction of the radius of eccentricity of the pinions by suitable adjustment of the levers, 27, 28 and thus of the phase of the oscillation of the wings and the lift factor is increased by increasing the angle of incidence. The aircraft may be kept on an even keel by automatic gyrohydraulic mechanism acting to vary the lift of the forward wing sets. The speed of rotation of the wings may be maintained at a predetermined value irrespective of the aircraft speed. For this purpose, the levers 27, 28 are arranged as shown in Fig. 12 to be moved in opposite directions by a hydraulic motor 58 controlled by a valve 48 operated through lever 44 by a speed governor 42 driven from the carrier 10. Thus if due to an increase of aircraft speed, the rotation speed of the wings tends to increase, pressure liquid is supplied to the left-hand side of piston 59 causing movement of the levers 27, 28 towards each other by the links 63, 64. This decreases the eccentricity of the pinions and thus the speed of rotation of the wings about the main axis a. The valve sleeve 49 is connected by link 64 to give a follow-up action. The speed of rotation is set at the desired value by adjustment of the pivot 45 of lever 44 by the screw-and-nut device 47. In Fig. 9, the wing shafts are shown as parallel to the axis a. A construction is also shown in which the wing shafts diverge as in Fig. 1, the pinions being bevelled to permit this. The carriers 10 may be coupled together in pairs on opposite sides of the aircraft to ensure that opposite sets of wings rotate at the same speed or all the carriers may be coupled together. Power may be applied to boost up the rotation of the wings to their natural speed.