In an aircraft gas turbine engine equipped with a bleed-off valve that bleeds intake air compressed by a compressor exterior and an electric actuator that drives the valve when current is supplied, a required valve opening θr and a current value Ia corresponding thereto are calculated and Ia is supplied to the actuator to bring valve opening θ to the required opening θr. Then Ia is compared with a current value Ib and if Ia exceeds 1b, the valve is estimated to have failed and another current value Ic is calculated and Ic is supplied to enlarge valve opening toward wide-opening θw. Then a current value Id is calculated and supplied to decrease valve opening toward θr. Next, Id is compared with Ib and the valve is determined normal when Id is equal to or smaller than 1b. If not, it is determined to be faulty.

A gas turbine engine and methods of operation include a low pressure electric motor-generator arranged for selective operation in a generator mode to generate electrical power or a drive mode to assist rotation of a low pressure drive shaft of the engine.

A gas turbine engine and methods of operation include a low pressure electric motor-generator arranged for selective operation in a generator mode to generate electrical power or a drive mode to assist rotation of a low pressure drive shaft of the engine.

A gas turbine engine actuation system includes a gas turbine engine, an actuation device, an actuator, and a power source. The gas turbine engine includes a compressor section, a combustion section, a turbine section, and a rotating shaft. The actuation device is operable with the compressor section, combustion section, turbine section, or a combination thereof. The actuator is operationally coupled to the actuation device and includes an electric actuator configured to convert electrical current into mechanical power. The power source is configured to supply electrical current to the actuator, alone or in tandem with a hydraulic actuator.

A gas turbine engine actuation system includes a gas turbine engine, an actuation device, an actuator, and a power source. The gas turbine engine includes a compressor section, a combustion section, a turbine section, and a rotating shaft. The actuation device is operable with the compressor section, combustion section, turbine section, or a combination thereof. The actuator is operationally coupled to the actuation device and includes an electric actuator configured to convert electrical current into mechanical power. The power source is configured to supply electrical current to the actuator, alone or in tandem with a hydraulic actuator.

A system and a method include an engine having one or more vanes. An actuator is coupled to the one or more vanes. The actuator is configured to move the one or more vanes between different positions. A control unit is coupled to the actuator. The control unit is configured to operate the actuator to move the one or more vanes between the different positions. The control unit is disposed on or within the engine.

An apparatus is provided for an aircraft propulsion system. This apparatus includes a variable area nozzle apparatus. The variable area nozzle apparatus includes a plurality of panels, a plurality of inter-panel members and an actuation system. The panels are arranged circumferentially about an axial centerline. The panels include a first panel and a second panel. The inter-panel members are arranged circumferentially about the axial centerline. The inter-panel members include a first inter-panel member between and connected to the first panel and the second panel. The first inter-panel member is configured from or otherwise includes an elastomeric material. The actuation system is configured to move the panels and the inter-panel members between a restricted flow arrangement and an unrestricted flow arrangement. The actuation system includes a first linkage and a second linkage. The first linkage is coupled to the first panel. The second linkage is coupled to the second panel.

An apparatus is provided for an aircraft propulsion system. This apparatus includes a variable area nozzle apparatus. The variable area nozzle apparatus includes a plurality of panels, a plurality of inter-panel members and an actuation system. The panels are arranged circumferentially about an axial centerline. The panels include a first panel and a second panel. The inter-panel members are arranged circumferentially about the axial centerline. The inter-panel members include a first inter-panel member between and connected to the first panel and the second panel. The first inter-panel member is configured from or otherwise includes an elastomeric material. The actuation system is configured to move the panels and the inter-panel members between a restricted flow arrangement and an unrestricted flow arrangement. The actuation system includes a first linkage and a second linkage. The first linkage is coupled to the first panel. The second linkage is coupled to the second panel.

A system may comprise a sensor configured to measure a characteristic of an engine component. A valve assembly may have an airflow outlet in fluid communication with the engine component. The valve assembly may include a first valve. A first valve control device may be coupled to the first valve and configured to control the first valve based on a measurement by the sensor. A second valve may be in fluidic series with the first valve. A second valve control device may be coupled to the second valve and configured to control the second valve based on the measurement by the sensor.

A system may comprise a sensor configured to measure a characteristic of an engine component. A valve assembly may have an airflow outlet in fluid communication with the engine component. The valve assembly may include a first valve. A first valve control device may be coupled to the first valve and configured to control the first valve based on a measurement by the sensor. A second valve may be in fluidic series with the first valve. A second valve control device may be coupled to the second valve and configured to control the second valve based on the measurement by the sensor.