Rotary wing aircraft split segmented duct shrouded propeller tail

Abstract

An improved version of a vectored thrust ducted propeller tail assembly or 'ring tail' for rotary wing aircraft in which a deflecting surface or surfaces is pivotally mounted behind the shrouded propeller in the tail duct for rotation transversely of the duct interior in deflecting the propeller slip stream transversely of the duct establishing a transversely directed thrust for providing rotor torque counteracting and aircraft yaw control. In the improved version the slip stream deflecting surfaces are pivotally supported to extend transversely across the duct rear exit in both directions as will deflect the propeller slip stream either out the left or the right sides or out both the left and right sides of the duct end. In this version the deflecting surfaces comprise a rudder surface pivotally mounted to swing between a neutral position coincident with the duct longitudinal axis and fully deflected positions extending transversely across the duct interior in either direction and a pair of arcuate duct end sectors each configured to partially circumferentially overlie an end portion of the respective opposite lateral sides of the duct. The sectors are pivotally supported for rotation between a stowed position in which each sector of the pair spans a duct end portion of respective opposite lateral sides of the duct and alternate extended positions in which both sectors are arranged in a juxtaposed array with adjacent side edges abutting.