Rotary wing aircraft shrouded propeller tail assembly.

摘要

There is disclosed an improved structure for the shrouded propeller tail duct or "ring tail" of a rotary wing aircraft providing rotor torque counteracting aircraft yaw control forces in all flight conditions of hovering and high speed cruising flight. The rear portion of one lateral side (32) of the shrouded propeller duct comprises a plurality of overlying arcuate segments (36,37,38) that are pivotally supported for rotation relative to each other about a vertical axis between a retracted position for high speed flight in which the segments (36,37,38) are in mutually overlying position constituting one side of the duct and an extended position in which the segments (36,37,38) are in a mutually adjoining relationship with their edges only overlapping and extending obliquely transversely of the duct interior in the form of a continuous, rearwardly projecting and transversely extending arcuate extension of the interior wall of one side of the duct. This extendable elbow duct section, in combination with a vertically extending rudder vane (20) which preferably comprises a plurality of tandemly arranged sections (21,22,23,24) with pivotal connections to each other for rotation relative to one another about respective axis between a neutral position with the vane sections (21,22,23,24) in alignment and a deflected position with the vane sections (21,22,23,24) angularly arranged relative to each other in the form of an arc extending transversely of the duct forwardly of and congruent with the contour of the fully extended duct segments, provides a propeller slip stream containing and deflecting structure that smoothly deflects the slip stream from the propeller through 90 degrees with minimum turbulence when the aircraft is in a slow speed and hover flight condition.