Patent GB-708738-A (GB)
Title: Impeller propelled aerodynamic bodies
IPC: B64C29/00
Filed: 1951-06-29
Abstract: 708,738. Aircraft: screw propellers. DOAK. E. R. June 29, 1951 [July 1, 1950], No. 15502/51. Classes 4 and 114 An aircraft includes a body provided with one or more aerodynamic units, said body having an upper, generally convex surface and a lower, generally convex surface, and having aerofoil characteristics in longitudinal section, margins of said upper and lower surfaces being connected, in part at least, to form entering and trailing edges each of said aerodynamic units comprising, in combination with said body and surfaces. an inlet port for each said unit in the upper surface and an outlet port for each said unit in the lower surface, and said inlet port and outlet port for each unit being connected by an inclined passageway extending through the said body, said passageway being provided with a virtually imperforate wall which is continuous and in confluent, anastomotic relation to the upper surface of the body, and a power driven impeller provided with counter-rotating torque and counteracting impeller sections mounted for rotation along the axis of said passageway, for drawing air into said passageway along the upper surface of the body and discharging such air downwardly in a direction parallel to the axis of the pasageway so as to produce a downwardly directed jet and creating a lift along said upper surface, resulting in a vertical reaction in excess of thirty pounds per square foot of area swept by the impeller. The aircraft comprises a body portion 10<SP>1</SP> of discus shape having upper and lower convex surfaces 11<SP>1</SP> and 12<SP>1</SP> so that the whole body is of aerodynamic form. Elevators 19, 19<SP>1</SP> and a rudder 23 are provided at the trailing edge 18 of the fuselage and lateral stabilizers having upwardly bent ends 25<SP>1</SP> are pivotally mounted on substantially vertical axes 26 and are controlled by actuators 27. A canopy 24 and undercarriage 28 are fitted. A circular passageway 13<SP>1</SP> extends through the body 10<SP>1</SP> at an angle of preferably between 30 degrees and 85 degrees to the plane passing through the leading and trailing edges and at a point located between 0.3 and 0.5 of the length of the chord of the body. An impeller in the passageway 13<SP>1</SP> comprises two contra-rotating sections which draw air from the upper surface and eject a downwardly and rearwardly directed jet of air which provides both lift and forward thrust. As shown in Fig. 6 the duct for the impeller unit is provided with upper elements 50, 50<SP>1</SP> actuated by jacks 51, 51<SP>1</SP> which may be moved to the positions shown by chain dotted lines to restrict the volume of air drawn into the duct and spoilers 52, 52<SP>1</SP> are located in the lower end of the duct. The members 50, 50<SP>1</SP> and 52, 52<SP>1</SP> may be moved in unison to control the volume of air passed through the duct or they may be moved differentially to provide a directional control effect. An embodiment, Fig. 9 (not shown), refers to a plurality of ducts and impeller units. Each impeller comprises contrarotating elements driven from a shaft 37 and having hub portions 43, 44 which together are frustoconical in form. Each blade is defined by a root line 54, an outer edge 46 in proximity with the wall of the passageway 13<SP>1</SP> and forming an angle of between 35 degrees and 60 degrees to the impeller shaft axis and upper and lower edges 41, 42 so shaped that the blade has a concave operating surface, the impeller being stated to produce an axial thrust in excess of 30 pounds per square foot.