GB1038931A - Improvements in or relating to aerial vehicles - Google Patents

Abstract

1,038,931. Vertical take off aircraft; air cushion vehicles. PIASECKI AIRCRAFT CORPORATION. Jan. 19, 1965, No. 2236/65. Headings B7G, B7K and B7W. A vertical take off aircraft comprises a platform 11 (Figs. 1 and 2, not shown) with two contra-rotating ducted rotors 15 arranged in tandem and driven together by engines 21, 21a. The blades 15 of each rotor are variable in pitch and connected by links 33 to a spider 34 (Fig. 5, not shown) tilted by push rods 40, 41 for cyclic pitch control, and moved axially by a push rod 36 for collective pitch control. The collective pitch of the two rotors may be varied differentially for longitudinal control. Longitudinal and transverse hinged vanes 24, 25 beneath the rotors are also provided for control purposes. The platform, or the individual rotor ducts, are surrounded by an inflatable fairing 29, the inflation pressure of which may be variable to control the local air flow. Retractable spoilers 50 (Fig. 7, not shown) may also be fitted to the forward parts of the duct intakes to break up high negative pressure regions. The platform may be provided with skirts (Figs. 9-11, not shown) to help contain an air cushion beneath the rotors andthesemaybo located all round the platform or just at the sides. They may be retractable to reduce drag. The aircraft may be propelled on the ground by driving an undercarriage wheel from the engines, through a clutch. The rotors may lie in the same plane, as shown, or the rear rotor may be raised to improve the airflow to it. The duct intakes are conversely curved, the curvature having no discontinuity.