A method for active bi-directional control of an outer structure of a gas turbine engine comprises sending, by a controller, a first control signal to a power electronics for varying an electric current supplied to a heating element to cause the outer structure to move in a first radial direction, and sending, by the controller, a second control signal to a valve assembly for varying a cooling air flow supplied to the outer structure to cause the outer structure to move in a second radial direction. The first radial direction is opposite the second radial direction.

The subject matter of this specification can be embodied in, among other things, an actuator apparatus includes an output member configured to actuate between a first positional configuration and a second positional configuration, a source fluid reservoir, a fluid velocity resistor configured to provide a predetermined resistance to fluid flow, a fluid velocity fuse configured to flow fluid flows having a first predetermined range of fluid velocities and to block fluid flows having second predetermined range of fluid velocities, and a fluid actuator assembly configured to urge fluid flow from the source fluid reservoir through the fluid velocity resistor and the fluid velocity fuse based on actuation of the output member.

The subject matter of this specification can be embodied in, among other things, a thrust reverser tertiary lock apparatus that includes a probe affixed to an aircraft engine frame and having a shaft having a barb at a first end and configurable to a first configuration and a second configuration, and a receiver affixed to a thrust reverser transcowl slider configured to accommodate the barb and having an end wall with an aperture defined therein, the aperture shaped to permit escapement of the barb in the first configuration and prevent escapement of the barb in the second configuration.

Improved gimbal systems, apparatus, articles of manufacture and associated methods are disclosed. Examples include a panel including a window, the window to define an aperture for a sensor; a platform to mount the sensor, the platform including a first pinion; a first stepper motor to move the first pinion about a first arched rack; a gimbal body including the first arched rack and a second pinion; and a second stepper motor to move the second pinion about a second arched rack, the second arched rack positioned orthogonally to the first arched rack.

A surge control system includes a rotor system with at least one compressor section and at least one turbine section operably coupled to a shaft. The surge control system also includes sensors configured to collect sensor data from the rotor system, an electric motor operably coupled to the rotor system, and a controller. The controller is operable to detect surge event from the sensor data, determine an amount of power to apply to the rotor system, and increase the amount of power provided to the rotor system to recover from the surge event.

A gas turbine engine has an engine static structure. At least one component rotatable relative to the engine static structure about an engine axis of rotation. A fan is coupled to at least one component for rotation about the engine axis of rotation. An actuator is mounted to the engine static structure, wherein the actuator is activated to prevent the fan from rotation and is inactivated to allow the fan to rotate. A method for preventing rotation of a fan in a gas turbine engine is also disclosed.

A control system for a variable area fan nozzle (VAFN) is disclosed. The VAFN may have a plurality of petals and may be for use with a gas turbine engine. The control system may include a primary system configured to acquire primary data indicative of an operating condition of the VAFN, a secondary system configured to acquire secondary data indicative of a current operating condition of the gas turbine engine, and a control module in operative communication with the primary system and the secondary system. The control module may be configured to: determine a nozzle area of the VAFN based at least in part on the primary data, adjust the determined nozzle area based on the secondary data, and position the plurality of petals according to the adjusted nozzle area.

Pitch actuation system for a turbine engine propeller, comprising an actuator, a movable part of which is designed to be connected to blades of the propeller so as to rotate said blades relative to blade pitch-setting axes, characterised in that the actuator is an electromechanical actuator and comprises first electrical means for controlling blade pitch, which means comprise at least two electric motors for driving a common rotor, and a transmission screw rotated by said common rotor, and in that the system further comprises a nut, through which said transmission screw passes and which is designed to cooperate with the blades so as to move them.

An electromechanical component arrangement for a gas turbine engine includes a mechanical component located at a first side of a firewall of a gas turbine engine and an electronic module of the electromechanical component in communication with the mechanical component separated from the mechanical component by a firewall, the firewall comprising a first side and a second side, the second side having a lower operating temperature than the first side. A vibration isolation structure is located at the second side. The electronic module is connected thereto and includes at least one vibration isolator secured to the firewall to vibrationally isolate the electronic module from gas turbine engine vibrations.

An electromechanical system for a gas turbine engine includes a mechanical component located at a first side of a firewall of a gas turbine engine, and an electrical motor located at a second side of the firewall and configured to drive the mechanical component. The electrical motor mechanically connected to the mechanical component through a firewall opening in the firewall, the first side having a higher operating temperature than the second side. An electrical connection extends between the mechanical component and the electrical motor via the same firewall opening.