Abstract: A fuel delivery system for a gas turbine engine is disclosed which includes a continuously variable drive assembly having a driving portion operatively associated with a gearbox of the gas turbine and a driven portion operatively associated with a fuel pump of the gas turbine, and a governor for controlling a drive ratio of the drive assembly to vary fuel pump flow performance over a range of engine operating conditions.

Abstract: A reservoir includes first and second chambers, and a piston having first and second ends disposed in the first and second chambers, respectively. The first and second ends isolate a first area from a second area within the first and second chambers. The first area of the first chamber is in fluid communication with a high pressure fluid source and the second area of the first chamber is in fluid communication with a low pressure fluid source. An orifice is formed in the first end and is configured to allow fluid communication between the upper and lower areas of the first chamber. A pumping system and an aircraft are also disclosed.

Abstract: A cooling flow circuit is provided and includes a main line having first and second sections ported to piston extend and return sides of the gas turbine engine actuator, respectively, an orifice disposed along the main line between the first and second sections, a bypass line and a bypass valve. The bypass line is fluidly coupled to the first and second sections at opposite ends thereof, respectively. The bypass valve is disposed along the bypass line between the opposite ends thereof. The bypass valve has a variable flow area which is responsive to a pressure differential between the first and second sections.

Abstract: A fuel system for an aircraft includes a main pump, a servo pump, a servo minimum pressure valve, and a servo pump bypass connection element. The main pump receives fuel from a source. The servo pump also receives fuel from the source. The servo minimum pressure valve receives fuel from the main pump supplied through a first line and the valve receives fuel from the servo pump supplied through a second line. The servo pump bypass connection element connects the first line and the second line.

Abstract: A filter screen includes a plate body with an upstream surface, an opposed downstream surface, and an array of apertures extending between the upstream surface and the downstream surface. A polytetrafluoroethylene-based layer overlays the upstream surface between apertures of the aperture array, the polytetrafluorethylene-based layer being conformally disposed over the upstream surface of the plate body and spanning the upstream surface between the apertures of the aperture array to slow deposition of carbonaceous deposits on the filter screen.

Abstract: An example method of calibrating a controller for controlling or sensing data from a device includes decoding an encoded image depicted on a surface associated with a device to obtain an identifier of the device and calibration data for an output of the device. The calibration data is utilized by a controller for one of controlling and sensing data from the device. An example system for controlling or sensing data from a device is also disclosed.

Abstract: A shut-off valve system includes a tank having an inlet and an outlet with a flow path defined therebetween. A float within the tank occludes the tank outlet at a first fluid level under positive G forces and unoccludes the tank outlet at a second fluid level under positive G forces. A flow restricting orifice and/or a hydraulic fuse is downstream of float and tank outlet to restrict fluid communication between tank outlet and an ejector pump. A method for restricting flow in an ecology fuel return system includes recovering fuel from engine components, communicating the fuel to an inlet of a fuel tank, pumping the fuel from an outlet of fuel tank to an inlet of an engine when a float within tank unoccludes the outlet of the fuel tank, and restricting fluid flow from tank outlet to an ejector pump with a flow restricting orifice and/or a hydraulic fuse.

Abstract: A cooling flow circuit is provided and includes a main line having first and second sections ported to piston extend and return sides of the gas turbine engine actuator, respectively, an orifice disposed along the main line between the first and second sections, a bypass line and a bypass valve. The bypass line is fluidly coupled to the first and second sections at opposite ends thereof, respectively. The bypass valve is disposed along the bypass line between the opposite ends thereof. The bypass valve has a variable flow area which is responsive to a pressure differential between the first and second sections.

Abstract: A shut-off valve includes a float and a negative G control component. The float is configured to occlude a tank outlet at a first fluid level and 1 G and unocclude the tank outlet at a second fluid level and 1 G. The negative G control component is operatively connected to the float to limit fluid, e.g. liquid or gas, communication between a tank outlet and an ejector pump during negative G events. An ecology fuel return system includes a tank, an ejector pump, a float, and a negative G control component, as described above. The tank has an inlet and an outlet. The inlet is configured to be in fluid communication with components of an engine. The ejector pump is in fluid communication with the tank outlet and is configured to pump fuel from the tank to a fuel pump inlet of an engine.

Abstract: A shut-off valve includes a float and a negative G control component. The float is configured to occlude a tank outlet at a first fluid level and 1 G and unocclude the tank outlet at a second fluid level and 1 G. The negative G control component is operatively connected to the float to limit fluid, e.g. liquid or gas, communication between a tank outlet and an ejector pump during negative G events. An ecology fuel return system includes a tank, an ejector pump, a float, and a negative G control component, as described above. The tank has an inlet and an outlet. The inlet is configured to be in fluid communication with components of an engine. The ejector pump is in fluid communication with the tank outlet and is configured to pump fuel from the tank to a fuel pump inlet of an engine.

Abstract: A filter screen includes a plate body with an upstream surface, an opposed downstream surface, and an array of apertures extending between the upstream surface and the downstream surface. A polytetrafluoroethylene-based layer overlays the upstream surface between apertures of the aperture array, the polytetrafluorethylene-based layer being conformally disposed over the upstream surface of the plate body and spanning the upstream surface between the apertures of the aperture array to slow deposition of carbonaceous deposits on the filter screen.

Abstract: A fuel system for an aircraft includes a main pump, a servo pump, a servo minimum pressure valve, and a servo pump bypass connection element. The main pump receives fuel from a source. The servo pump also receives fuel from the source. The servo minimum pressure valve receives fuel from the main pump supplied through a first line and the valve receives fuel from the servo pump supplied through a second line. The servo pump bypass connection element connects the first line and the second line.

Abstract: A shut-off valve includes a float and a negative G control component. The float is configured to occlude a tank outlet at a first fluid level and 1 G and unocclude the tank outlet at a second fluid level and 1 G. The negative G control component is operatively connected to the float to limit fluid, e.g. liquid or gas, communication between a tank outlet and an ejector pump during negative G events. An ecology fuel return system includes a tank, an ejector pump, a float, and a negative G control component, as described above. The tank has an inlet and an outlet. The inlet is configured to be in fluid communication with components of an engine. The ejector pump is in fluid communication with the tank outlet and is configured to pump fuel from the tank to a fuel pump inlet of an engine.

Abstract: An actuator system having various features is disclosed. An actuator system may have a first and a second electrohydraulic servo valve. A control selector may connect one of the electrohydraulic servo valves to a cylinder and may isolate the other electrohydraulic servo valve to ameliorate leakage in response to a switching solenoid valve operating. In this manner, one electrohydraulic servo valve may be connected to a cylinder to operate the cylinder, and the other electrohydraulic servo valve may be isolated from the cylinder, for example, to provide a standby electrohydraulic servo valve.

Abstract: A shut-off valve includes a float and a negative G control component. The float is configured to occlude a tank outlet at a first fluid level and 1 G and unocclude the tank outlet at a second fluid level and 1 G. The negative G control component is operatively connected to the float to limit fluid, e.g. liquid or gas, communication between a tank outlet and an ejector pump during negative G events. An ecology fuel return system includes a tank, an ejector pump, a float, and a negative G control component, as described above. The tank has an inlet and an outlet. The inlet is configured to be in fluid communication with components of an engine. The ejector pump is in fluid communication with the tank outlet and is configured to pump fuel from the tank to a fuel pump inlet of an engine.

Abstract: A shut-off valve system includes a tank having an inlet and an outlet with a flow path defined therebetween. A float within the tank occludes the tank outlet at a first fluid level under positive G forces and unoccludes the tank outlet at a second fluid level under positive G forces. A flow restricting orifice and/or a hydraulic fuse is downstream of float and tank outlet to restrict fluid communication between tank outlet and an ejector pump. A method for restricting flow in an ecology fuel return system includes recovering fuel from engine components, communicating the fuel to an inlet of a fuel tank, pumping the fuel from an outlet of fuel tank to an inlet of an engine when a float within tank unoccludes the outlet of the fuel tank, and restricting fluid flow from tank outlet to an ejector pump with a flow restricting orifice and/or a hydraulic fuse.

Abstract: A fuel system for a gas turbine engine includes an engine fuel manifold, a hydraulic actuator, and a drain piston assembly. The hydraulic actuator actuates in response to a change in pressures within the hydraulic actuator. The drain piston assembly is fluidically connected to both the hydraulic actuator and the engine fuel manifold. The drain piston assembly receives fuel from the engine fuel manifold and sends fuel to the hydraulic actuator during engine shut down.

Abstract: An actuator system having various features is disclosed. An actuator system may have a first and a second electrohydraulic servo valve. A control selector may connect one of the electrohydraulic servo valves to a cylinder and may isolate the other electrohydraulic servo valve to ameliorate leakage in response to a switching solenoid valve operating. In this manner, one electrohydraulic servo valve may be connected to a cylinder to operate the cylinder, and the other electrohydraulic servo valve may be isolated from the cylinder, for example, to provide a standby electrohydraulic servo valve.

Abstract: A shut-off valve includes a float and a negative G control component. The float is configured to occlude a tank outlet at a first fluid level and 1 G and unocclude the tank outlet at a second fluid level and 1 G. The negative G control component is operatively connected to the float to limit fluid, e.g. liquid or gas, communication between a tank outlet and an ejector pump during negative G events. An ecology fuel return system includes a tank, an ejector pump, a float, and a negative G control component, as described above. The tank has an inlet and an outlet. The inlet is configured to be in fluid communication with components of an engine. The ejector pump is in fluid communication with the tank outlet and is configured to pump fuel from the tank to a fuel pump inlet of an engine.

Abstract: A fuel flow system for a gas turbine includes a first pump, a main fuel flow path and a second pump. The first pump is connected to an actuator and a metering valve. The main fuel flow path is formed between the first pump and the metering valve. The second pump is connected to the main fuel flow path and supplements the fuel flow from the first pump under certain conditions. The second pump and first pump are in parallel.