Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a translating inlet assembly are provided. In one embodiment, a core engine of a gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include an inner flowpath surface. A core casing can enclose the core engine. A forward end of the core casing can include a translating inlet assembly moveable between a first position and a second position. The translating inlet assembly and the inner flowpath surface can together define an inlet to an engine airflow path. A translating inlet assembly can define a first inlet area in the first position and a second inlet area in the second position, the first inlet area being greater than the second inlet area.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a valved airflow passage assembly are provided. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include a compressor. The gas turbine engine can further include a valved airflow passage assembly comprising a valve and a duct, the duct defining an inlet in airflow communication with the engine airflow path at a location downstream of the compressor and an outlet in airflow communication with the engine airflow path at a location upstream of the compressor, the duct comprising an airflow passage extending between the inlet and outlet. The valve can be operable with the airflow passage for controlling an airflow through the airflow passage to adjust airflow distortion.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a translating inlet assembly are provided. In one embodiment, a core engine of a gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include an inner flowpath surface. A core casing can enclose the core engine. A forward end of the core casing can include a translating inlet assembly moveable between a first position and a second position. The translating inlet assembly and the inner flowpath surface can together define an inlet to an engine airflow path. A translating inlet assembly can define a first inlet area in the first position and a second inlet area in the second position, the first inlet area being greater than the second inlet area.

Abstract: Methods and systems for identifying rub events of a gas turbine engine are provided. In one exemplary aspect, one or more power level changes of the turbine engine are identified from engine operating data. For a particular identified power level change, a magnitude of the power level change and a rate of the power level change are calculated. The calculated magnitude and rate of the given power level change define a data point that is plotted on a chart of the magnitude versus the rate of power level change. The data points are filtered based on one or more operating parameters, such as flight phase, to obtain a severity threshold specific to the operating conditions of the engine/aircraft at the time the power level change was performed. One or more data points are then compared to the severity threshold to identify possible rub events.

Abstract: Instrumented airflow path components configured to determine airflow path distortion in an airflow path of a gas turbine engine (e.g., using for propulsion of an aircraft) are provided. In one embodiment, a gas turbine engine for an aircraft can include a compressor section, a combustion section, and turbine section in series flow. The compressor section, combustion section, and turbine section define at a portion of an engine airflow path for the gas turbine engine. The gas turbine engine further includes one or more members extending at least partially into the engine airflow path of the gas turbine engine and one or more pressure sensor devices at least partially integrated into the one or more members extending at least partially into the engine airflow path. The one or more pressure sensor devices are configured to obtain measurements for determining a distortion condition for the gas turbine engine.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a translating inlet assembly are provided. In one embodiment, a core engine of a gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include an inner flowpath surface. A core casing can enclose the core engine. A forward end of the core casing can include a translating inlet assembly moveable between a first position and a second position. The translating inlet assembly and the inner flowpath surface can together define an inlet to an engine airflow path. A translating inlet assembly can define a first inlet area in the first position and a second inlet area in the second position, the first inlet area being greater than the second inlet area.

Abstract: A thrust reverser assembly and a method of operating an aircraft during a taxi mode of operation are provided. The thrust reverser assembly includes one or more actuator assemblies configured to modulate a position of a moveable portion over a continuous range of travel between a fully stowed position and a fully deployed position, such that an air flow through said thrust reverser bleed passage is correspondingly varied. The thrust reverser assembly also includes a throttle device that includes a first, ground idle power level position and a second, forward thrust mode position. Movement into the second position may be actuated separately and differently from movement into the first position. An actuator intermediate lock may inhibit actuation of the intermediate forward thrust mode of operation until a plurality of preconditions is met.

Abstract: A thrust reverser assembly and a method of operating an aircraft during a taxi mode of operation are provided. The thrust reverser assembly includes one or more actuator assemblies configured to modulate a position of a moveable portion over a continuous range of travel between a fully stowed position and a fully deployed position, such that an air flow through said thrust reverser bleed passage is correspondingly varied. The thrust reverser assembly also includes a throttle device that includes a first, ground idle power level position and a second, forward thrust mode position. Movement into the second position may be actuated separately and differently from movement into the first position. An actuator intermediate lock may inhibit actuation of the intermediate forward thrust mode of operation until a plurality of preconditions is met.

Abstract: Thrust reverser assemblies and a method of operating an aircraft during a landing approach mode of operation are provided. The thrust reverser assembly includes a moveable portion that is moveable over a continuous range of travel between a fully stowed position and a fully deployed position. Movement away from the fully stowed position opens a bleed passage. An actuator assembly coupled to the moveable portion is operable in an intermediate forward thrust mode to modulate a position of the moveable portion along the continuous range of travel, such that an air flow through the bleed passage is correspondingly varied. A throttle device includes a first position associated with deployment of, and a second position associated with engagement of, the intermediate forward thrust mode of operation. A drag flap assembly may extend from the bleed passage during the intermediate forward thrust mode of operation.

Abstract: Methods and systems for identifying rub events of a gas turbine engine are provided. In one exemplary aspect, one or more power level changes of the turbine engine are identified from engine operating data. For a particular identified power level change, a magnitude of the power level change and a rate of the power level change are calculated. The calculated magnitude and rate of the given power level change define a data point that is plotted on a chart of the magnitude versus the rate of power level change. The data points are filtered based on one or more operating parameters, such as flight phase, to obtain a severity threshold specific to the operating conditions of the engine/aircraft at the time the power level change was performed. One or more data points are then compared to the severity threshold to identify possible rub events.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a secondary airflow passage assembly are disclosed. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. A casing can enclose the gas turbine engine and be at least partially exposed to a bypass airflow. The gas turbine engine can further include a secondary airflow passage assembly comprising a door and a duct, the duct defining an inlet located on the casing, the duct defining an outlet in airflow communication with the engine airflow path, the duct comprising an airflow passage extending between the inlet and outlet. The door can be moveable between an open and closed position to allow a portion of the bypass airflow to flow through the airflow passage to adjust airflow distortion.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a valved airflow passage assembly are provided. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include a compressor. The gas turbine engine can further include a valved airflow passage assembly comprising a valve and a duct, the duct defining an inlet in airflow communication with the engine airflow path at a location downstream of the compressor and an outlet in airflow communication with the engine airflow path at a location upstream of the compressor, the duct comprising an airflow passage extending between the inlet and outlet. The valve can be operable with the airflow passage for controlling an airflow through the airflow passage to adjust airflow distortion.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a translating inlet assembly are provided. In one embodiment, a core engine of a gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include an inner flowpath surface. A core casing can enclose the core engine. A forward end of the core casing can include a translating inlet assembly moveable between a first position and a second position. The translating inlet assembly and the inner flowpath surface can together define an inlet to an engine airflow path. A translating inlet assembly can define a first inlet area in the first position and a second inlet area in the second position, the first inlet area being greater than the second inlet area.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a secondary airflow passage assembly are disclosed. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. A casing can enclose the gas turbine engine and be at least partially exposed to a bypass airflow. The gas turbine engine can further include a secondary airflow passage assembly comprising a door and a duct, the duct defining an inlet located on the casing, the duct defining an outlet in airflow communication with the engine airflow path, the duct comprising an airflow passage extending between the inlet and outlet. The door can be moveable between an open and closed position to allow a portion of the bypass airflow to flow through the airflow passage to adjust airflow distortion.

Abstract: A method for controlling a gas turbine engine on an aircraft in response to airflow distortion in an airflow path of the gas turbine engine is provided. In one embodiment, a method can include determining, by one or more control devices located on an aircraft, a distortion condition associated with the gas turbine engine. The method can further include determining, by the one or more control devices, a stall margin for the gas turbine engine based at least in part on the distortion condition. The method can further include determining, by the one or more control devices, an engine control parameter based at least in part on the stall margin. The method can further include controlling, by the one or more control devices, a component of the gas turbine engine based at least in part on the engine control parameter.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine on an aircraft. The gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow. An engine airflow can flow through the compressor section, the combustion suction, and turbine section of the gas turbine engine. In one example, a method can include determining a distortion condition associated with one or more members extending at least partially into the engine airflow path. The method can further include controlling at least one sector of a plurality of sectors of variable guide vanes positioned at least partially within the engine airflow path to adjust the distortion condition.

Abstract: Instrumented airflow path components configured to determine airflow path distortion in an airflow path of a gas turbine engine (e.g., using for propulsion of an aircraft) are provided. In one embodiment, a gas turbine engine for an aircraft can include a compressor section, a combustion section, and turbine section in series flow. The compressor section, combustion section, and turbine section define at a portion of an engine airflow path for the gas turbine engine. The gas turbine engine further includes one or more members extending at least partially into the engine airflow path of the gas turbine engine and one or more pressure sensor devices at least partially integrated into the one or more members extending at least partially into the engine airflow path. The one or more pressure sensor devices are configured to obtain measurements for determining a distortion condition for the gas turbine engine.

Abstract: A method and systems for engine control of a vehicle propulsion system are provided. The system includes a plurality of engine model modules executing independently and programmed to receive engine operating condition values from a plurality of sensors positioned on an engine wherein each of the plurality of engine model modules is programmed to determine an estimate of a process parameter of a location in the engine where a sensor is not available, not present at the location, has failed, or is determined to be inaccurate. The system also includes an estimate source selector configured to determine model blending factors and a model blending module configured to determine an estimated virtual sensor value using the determined estimates from at least two of the plurality of engine model modules and the model blending factors.

Abstract: A method for estimating an operating parameter of a turbine engine is provided. The method includes receiving at least one sensor input, calculating the operating parameter using at least the one sensor input, and determining whether an anomaly is present in the calculated operating parameter using a redundancy system. An estimated operating parameter is output.

Abstract: A method and systems for engine control of a vehicle propulsion system are provided. The system includes a plurality of engine model modules executing independently and programmed to receive engine operating condition values from a plurality of sensors positioned on an engine wherein each of the plurality of engine model modules is programmed to determine an estimate of a process parameter of a location in the engine where a sensor is not available, not present at the location, has failed, or is determined to be inaccurate. The system also includes an estimate source selector configured to determine model blending factors and a model blending module configured to determine an estimated virtual sensor value using the determined estimates from at least two of the plurality of engine model modules and the model blending factors.