GB889807A - Rotary wing aircraft - Google Patents

Abstract

889,807. Rotary wing aircraft. McCARTY, L. C. March 26, 1959 [April 21, 1958], No. 10559 /59. Class 4. A rotary wing aircraft has flexible rotor blades each wound on a drum attached to the rotor head by arms and provided at its tip with a propulsion unit, such units being the sole source of power during powered flight of the aircraft, whereby the blades, when rotating, may be extended to operative, positions. The aircraft comprises a rotary hub 10 mounted on a fixed pylon 12 attached to a fuselage formed as an aerial crane, and consisting of landing gear 50, a tail boom 52 carrying a tail rotor, jet nozzle or other anti-torque device 48, and a compartment 54 secured to the tail boom to house a pilot. A fixed arm 16 and hinged arms 18 and 20, which may serve.as fuel tanks, form .part of rotor head 10 and they are inter-connected by actuators 28, 30 which are used to vary the lay lead attitude of the blades. The outer end of each arm carries a pivot 35 for reel assemblies 34 comprising spaced arms 66 each of which terminates in a projection 68 for engagement with a recess 70 in the nacelle 36 of a power plant, which as shown may drive a propeller 124 or may be a turbo-jet unit. Each pair of arms 66 carry a pivot 64 for a reel 88 on which is.wound a flexible rotor blade 74, the drum.being rotated for extension and retraction of the rotor blade by a motor (not shown) operating through a worm and worm gear 78. Longitudinal reinforcing filaments are embedded in each blade together with a fuel line 100 and electric leads 102. Lag-lead movements of the blades, when extended, are sensed by a roller device (not shown) which automatically varies the power output of the appropriate power plant or adjusts the appropriate actuator 28, 30 to correct the condition. The blades, are provided with trailing edge control .surfaces (not shown) for trimming purposes and main control surfaces 130 are provided at the rear of each nacelle whereby the cyclic and collective pitch of the blades may be varied. The pilot controls the aircraft in azimuth by adjustment of the antitorque rotor 48 by means of a hand control, but control in pitch and yaw is achieved by movement of a platform on which he stands, the platform being spring biased against movement on a central pivot. Each rotor blade comprises outer skins of impregnated fibreglass which sandwich a filler of foam .plastic. Although a crane type of aircraft, with a lifting sling 134, is described, the invention may be applied to rotary wing aircraft .having conventional fuselage arrangements.