Abstract: An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Abstract: Blade pitch varying means for use in a gas turbine engine are disclosed. The blade pitch varying means may be used on an engine with a single row or two counterrotating rows of variable pitch blades which are disposed outwardly from an annular gas flowpath and which are connected with a rotating airfoil within the flowpath. The blade pitch varying means comprise actuation means, bearing means, and gearing means. The actuation means are in a nonrotating reference frame disposed inwardly from the flowpath and deliver an axial force. The bearing means transmit the axial force from the nonrotating into a rotating reference frame which contains both the propulsor blade and the airfoil in the gas flowpath. The gearing means are located in the rotating reference frame and convert the axial force into a force for varying the blade pitch.