Abstract: A turbofan gas turbine propulsion engine includes a multi-speed transmission between the high pressure and low pressure turbines and associated high pressure and low pressure starter-generators. The multi-speed transmission reduces the operating speed range from the low pressure turbine to its associated starter-generator, and is configurable to allow the starter-generator associated with the low pressure turbine to supply starting torque to the engine.

Abstract: A turbofan gas turbine propulsion engine includes a system to transfer power from the low pressure turbine to the high pressure turbine and/or extract additional load from the low pressure turbine during certain turbofan engine operational conditions. The systems include a hydrostatic power transfer system that includes a hydraulic pump and a hydraulic motor coupled to the low pressure and high pressure turbine, respectively. The systems additionally include a mechanical and electrical load shifting/loading sharing systems that use clutches and gear assemblies to share and/or shift load between the turbines.

Abstract: A relatively small, lightweight valve actuator assembly that can withstand relatively high levels of vibration and shock includes a motor, a position sensor, and a drive belt mounted on an actuator housing assembly. The position sensor is preferably disposed within a sensor housing that is mounted on a side of the actuator housing assembly. As a result, the overall center-of-gravity (CG) and weight of the actuator assembly is significantly reduced, as is the overall size envelope.

Abstract: A lubrication system for supplying lubricants between two environments is provided. The first environment is disposed within a first housing and the second environment is disposed within a second housing having a supply opening and an exhaust opening. The system includes a lubricant supply tube disposed within the supply opening and configured to supply lubricant from the first environment to the second environment. The system also includes a receptacle disposed within the second housing and configured to receive lubricant supplied from the supply tube and to hold a predetermined volume of the lubricant. A check valve is disposed within the second housing and is in fluid communication with the exhaust opening. The check valve is configured to receive overflow lubricant from the receptacle, if the lubricant exceeds the predetermined volume and to provide a seal between the first and second environments in response to a pressure differential therebetween.

Abstract: An aircraft brake actuation system includes an actuator for selectively supplying a commanded brake force to one or more aircraft wheels. The actuator includes a ballscrew, a ballnut, and a plurality of balls. The ballscrew has a plurality of ball grooves formed on its inner surface, and is coupled to receive a rotational drive force. The ballnut is mounted against rotation, is disposed at least partially within the ballscrew, and includes a plurality of ball grooves formed on its outer surface. The plurality of balls are disposed within the ballnut ball grooves and at least selected ones of the ballscrew ball grooves.

Abstract: An air turbine starter is provided that includes a check valve assembly for placement between a first environment, at least a portion of which is at a first pressure (P1), and a second environment, at least a portion of which is at a second pressure (P2), wherein the difference between the first and second pressures generate a pressure force (Fp). The check valve assembly comprises a valve element disposed between the valve seat and the valve body, the valve element capable of being acted upon by a gravitational force (Fw), a viscous force of the fluid to be communicated between the gearbox assembly and the starter housing (Fv), a buoyancy force of the valve element (Fb), and the pressure force on the valve element (Fp), the valve element further configured to translate axially to a closed position when P2<P1 and Fw<Fv+Fb+Fp.

Abstract: An air turbine starter is provided that includes a check valve assembly. The check valve assembly comprises a valve body, a valve seat and a valve element. The valve body includes an inlet port, an outlet port, and a flow passage extending therebetween. The valve seat is coupled to the valve body, extends at least partially into the flow passage and has an opening therethrough. The valve element is disposed within the flow passage between the valve seat and the valve body outlet port. The valve element is also configured to translate axially between an open position and a closed position in response to a pressure differential between the inlet and outlet ports.

Abstract: A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

Abstract: Methods and apparatus are provided for monitoring an aircraft accessory. The apparatus comprises a processor associated with said aircraft accessory, a transducer coupled to said processor and operable to produce parametric data relating to said aircraft accessory and a memory coupled to said processor having baseline parametric data residing therein, wherein said baseline parametric data comprises the parametric data obtained during an acceptance test procedure. The method comprises installing a transducer configured to produce parametric data relating to said aircraft accessory, coupling said transducer to a processor associated with said aircraft accessory, coupling said processor to a memory associated with said aircraft accessory, recording baseline parametric data relating to said aircraft accessory in said memory during an acceptance test procedure for said aircraft accessory.