Failsafe nozzle actuating system

摘要

A nozzle failsafe nozzle actuating system for an aircraft gas turbine engine variable exhaust nozzle having a plurality of pivotal flaps circumferentially disposed about a nozzle centerline and bounding an exhaust gas flowpath in the nozzle is provided with a number of primary actuators which are operably connected to nozzle flaps for pivoting and setting an attitude of the flaps relative to the centerline and wherein each of the primary actuators is extendable between a fully extended position and a fully retracted position, and a failsafe nozzle actuating means for setting the attitude of each of the flaps to a failsafe attitude during a failsafe mode of the nozzle actuating system wherein the failsafe attitude is such that each of the primary actuators is at a partially retracted position between the fully extended and the fully retracted positions. A particular embodiment provides actuator assembly wherein a failsafe piston rod of the failsafe actuator is disposed concentrically about a primary rod of the primary actuator and a stop means is provided for the failsafe rod to engage the primary rod when the primary rod is being retracted and the failsafe rod is extended. <IMAGE>