Axially translating and radially tilting fan nozzle segments with combined actuation and position sensing

Abstract

An aircraft engine variable area fan nozzle structure disposed abaft a thrust reverser, including a sleeve translatable over a cascade array, comprises two semi cylindrical segments that can be axially translated and radially tilted to enlarge the fan duct exhaust area in order to optimize exhaust pressure and associated noise in high thrust circumstances such as on take-off, and to constrict that area under lower thrust conditions such as cruise. The segments are moved by actuators anchored to the fixed engine framework and independently of the thrust reverser translating sleeve. Each actuator incorporates a linear variable differential transformer acting as a fan nozzle position sensor. The tilting movement is imposed by the pivoting links of each segment to carriages that ride in a non-linear trackway secured to a thrust reverser translating sleeve slider. In an alternate embodiment of the invention, the thrust reverser sleeve actuator and the variable area fan nozzle actuator are coaxially mounted in a compact assembly anchored to stationary components of the nacelle.