GB666491A - Improvements in or relating to aircraft - Google Patents

Abstract

666,491. Convertible aircraft. GIROZ, H. E. June 17, 1948 [June 17, 1947; June 17, 1947], Nos. 16375/48 and 16376/48. Class 4. An aircraft comprises two propellers or sets of propellers arranged at opposite sides of its vertical median longitudinal plane and adapted to rotate about substantially horizontal axes, the radius of each propeller being greater than the distance of its axis from the supporting surface when the aircraft rests on its landing supports, an electric motor for each propeller or set of propellers, each motor being mounted in close proximity to the driven propeller shaft to form a propeller-motor unit, and means for producing a. take-off lift in the aircraft while preventing the blades of the propellers from fouling the supporting surface. In the embodiment shown in Fig. 1a, a fuselage 101 carries a pair of aeroplane wings 113 and accommodates turbo-generators. Propeller-motor units 105-108 comprising high frequency electric motors and a reduction gear drive rotary wings 109-112, are mounted on bearings 115, 116, 119, 120 for orientation from the position of normal flight shown on the right hand side of the figure to the position for landing and take-off shown in the left-hand side. The axes of orientation of the motor units are arranged to pass through the centres of gravity of the units. In a modification shown in Fig. 2c, a pair of wings 207, 208 carry motor units 205, 206 driving rotary wings 209, 210 and are orientable, about axes 215, 216 which coincide with the wing main-spar axes, from the normal flight position shown on the right to the hovering flight position shown on the left. The axes 215, 216 are arranged to pass through both the centre of gravity and the centre of pressure of the wings 207, 208. The wings may be orientated by geared servo motors. The pitch of the rotary wings may be varied to vary the thrust according to their use as propellers or helicopter rotors and also to control the aircraft in place of the normal control surfaces.. A differential electric control may be used for the latter purpose. The speed of the turbines driving the alternators may be kept constant, the fuel consumption being varied according to the rotor torques. The power output of an alternator mounted on the ground may assist or replace the power output of the alternator mounted in the aircraft for take-off, the power being transmitted by means of a long cable wound on a drum.