GB217588A - Improvements in aircraft - Google Patents

Abstract

217,588. Rietti, G. June 14, 1923, [Convention date]. Screw and like propellers.-The planes of an aeroplane are hinged about an axis or parallel axes at an angle to the leading and trailing edge so that when the tips are raised the two halves of the plane form screw blades adapted to raise the machine vertically when they are rotated about a vertical axis. The Figure shows two planes 1, 1<1> normally in horizontal alignment but adapted to be tilted about horizontal parallel axes a<1>, b<1> inclined to the line of flight. The axes a<1>, b<1> are carried by a frame 13 on a rotary cabin 2 supported by ball or roller bearings 4 on a fuselage 3. The planes are tilted by rods 14, 14<1> operated mechanically or by servomotors 7, 7'. Propellers 8, 8' are driven by engines 10, 10<1>, one of the propellers being reversible in pitch or rotation to enable the planes 1, 1<1> to be driven forwardly, when the machine is used as an aeroplane, or rotated with the cabin 2 about a vertical axis when used as a helicopter. Modifications are described in which the planes 1, 1<1> are pivoted about axes at their roots and are moved by endless cords connected to their tips or to intermediate portions, the propellers. 8, 8<1> being carried by the blades and driven from a single engine in the cabin 2 through jointed shafts. A biplane machine also is described.