GB918325A - Aircraft which take-off and land on a cushion of air - Google Patents

Abstract

918,325. Aircraft supported on air cushions during landing and take-off. DORNIERWERKE G.m.b.H. July 3, 1961 [July 2, 1960; July 9, 1960(3); Aug. 6, 1960(2)], No. 23892/61. Class 4. 4. An aircraft which can take-off and land on an air cushion formed beneath a wing which produces lift in forward flight, is a low wing monoplane with a straight central wing portion bounded by vertical surfaces between the central and the outer wing portions, and has blowers in which the airflow is transverse to their axes for producing the cushion and forward thrust, the blowers being installed chieffly in the central wing portion with their axes lying spanwise of the wing. Fig. 1 in a general view, showing the vertical surfaces 4 between the central wing portion 1 and the outer portions 2. These surfaces may act as skids on which the aircraft can rest and be manoeuvred on the ground, and may incorporate telescopic shock absorbing means, and each may also have a wheel just proud of the skid surface, to facilitate ground running and steering, the skid providing the main shock absorption on touch down, the landing run then being executed on the air cushion. A similar runner or runners may be provided under the fuselage. The runners may have collapsible floats, and water rudders. Fig. 4 shows a cross-section of the central wing portion, the blower 6 having a spanwise inlet duct 5, which may suck the boundary layer from the wing upper surface, and a spanwise discharge duct 15. A flap 12 and slidable surface 13 are extended as shown in broken lines to form the front and rear boundaries of the air cushion during take-off and landing, so that the cushion space is defined by the underside of the central wing portion, the vertical surfaces 4, and surfaces 12, 13 on either side of the fuselage. Laterally extending flaps beneath the fuselage may also define the cushion space. Surfaces 13 may also be flaps, and the flaps may be elastic or have flexible outer edges so as to be able to conform to the landing surface. Each flaps 12 may be extended, and nested automatically by being free to take up a position governed by the total pressure head on its foremost surface during forward movement, and the cushion pressure set up by the blower on its rearmost surface. To provide forward or rearward thrust during take off and landing, a flap 14 can control the direction of flow from duct 15, and surfaces 12 and 13 may be independently adjustable to vary the amounts of air escaping forwardly and rearwardly from the cushion. The surfaces 12 and 13 on opposite sides of the fuselage, or their outboard ends, may be movable differentially to set up unequal forward thrusts on the two sides of the fuselage, to provide yawing torques. The surfaces 13 and 14 may be coupled together. The inboard ends of the blowers extend into the fuselage, and the airflow therefrom may be used to provide forward thrust, lift, cooling air for the prime mover or movers, or compressed air for gas turbine engines. During flight, the airflow from duct 15 is used to provide lift and forward thrust.