Abstract: A method of controlling an aeronautical gas turbine engine may be performed with an electronic controller. The method may include determining an airfoil pitch control command for at least one of a plurality of airfoils of the aeronautical gas turbine engine based at least in part on an excitation load acting upon the aeronautical gas turbine engine, and outputting the airfoil pitch control command to one or more actuators actuatable to change a pitch angle of the at least one of the plurality of airfoils. The airfoil pitch control command may be configured to augment and/or compensate for the excitation load acting upon the aeronautical gas turbine engine. The method may be embodied by a non-transitory computer-readable medium that includes computer-executable instructions, which when executed by a processor associated with the electronic controller, cause the electronic controller to perform the method.

Abstract: An open rotor engine includes a core engine, a plurality of guide vanes positioned within or extending from the core engine; and a pitch change assembly operably coupled to the plurality of guide vanes. The pitch change assembly includes one or more actuators configured to change a pitch angle of respective ones of the plurality of guide vanes, and a plurality of linkage arms that are respectively movable by actuation of at least one of the one or more actuators. The plurality of linkage arms are directly or indirectly coupled to a corresponding one of the plurality of guide vanes. The plurality of linkage arms may have a length that differs from one another, and such length may orient a displacement or a range of motion of the respective linkage arm to an envelope of rotation about a guide vane axis that differs as between the plurality of guide vanes.

Abstract: An open rotor aeronautical engine may include a core engine, a plurality of unducted airfoils, and a pitch change assembly. The pitch change assembly may include an ensemble actuator assembly and a unitary actuator assembly. The ensemble actuator assembly may have one or more ensemble actuators and a unison ring that is movable by actuation of the one or more ensemble actuators to collectively change a pitch angle of the plurality of unducted airfoils. The unitary actuator assembly comprising a plurality of unitary actuators respectively coupled to a corresponding one of the plurality of unducted airfoils, the plurality of unitary actuators respectively movable to change the pitch angle of the corresponding one of the plurality of unducted airfoils.

Abstract: A control system for active stability management of a compressor element of a turbine engine is provided. In one example aspect, the control system includes one or more computing devices configured to receive data indicative of an operating characteristic associated with the compressor element. For instance, the data can be received from a high frequency sensor operable to sense pressure at the compressor element. The computing devices are also configured to determine, by a machine-learned model, a stall margin remaining of the compressor element based at least in part on the received data. The machine-learned model is trained to recognize certain characteristics of the received data and associate the characteristics with a stall margin remaining of the compressor element. The computing devices are also configured to cause adjustment of one or more engine systems based at least in part on the determined stall margin remaining.

Abstract: A monitoring and control system for a flow duct and a method for determining a component status of an operational component disposed within a flow passage of the flow duct utilizing the system are provided. In one exemplary aspect, the system includes at least two sensors that are disposed within the flow passage and configured to sense a characteristic of a fluid flowing therethrough. The sensors may be averaging sensors. Each sensor extends circumferentially about an axial centerline defined by the flow duct. The sensors are arranged in an overlapped arrangement. Particularly, the sensors extend circumferentially about the axial centerline such that the sensors physically overlap one another circumferentially. Additionally, the sensors may be disposed within the same or substantially the same plane axially. Signals generated by the sensors may be utilized to monitor and control the fluid and various operational components disposed within the flow passage.

Abstract: A fuel flow measuring system includes an ultrasonic fuel flow sensor. The fuel flow sensor includes a first transducer and a second transducer. The first transducer is excited at multiple different excitation frequencies and a voltage, an electric current, and a phase difference between the voltage and the electric current is sensed at the first transducer during excitation. Data points are generated based on the sensed readings and a model is fit to the data points to determine a complex impedance spectrum. The complex impedance spectrum indicates a range of excitation frequencies within a range of a peak resonance frequency of the first transducer. One or more characteristics of excitation signals directed to the second transducer are set based on the determined complex impedance spectrum. In this manner, the signal to noise ratio of ultrasonic signals emitted by the second transducer and received by the first transducer can be maximized.

Abstract: A fuel flow measuring system includes an ultrasonic fuel flow sensor. The fuel flow sensor includes a first transducer and a second transducer. The first transducer is excited at multiple different excitation frequencies and a voltage, an electric current, and a phase difference between the voltage and the electric current is sensed at the first transducer during excitation. Data points are generated based on the sensed readings and a model is fit to the data points to determine a complex impedance spectrum. The complex impedance spectrum indicates a range of excitation frequencies within a range of a peak resonance frequency of the first transducer. One or more characteristics of excitation signals directed to the second transducer are set based on the determined complex impedance spectrum. In this manner, the signal to noise ratio of ultrasonic signals emitted by the second transducer and received by the first transducer can be maximized.

Abstract: A monitoring and control system for a flow duct and a method for determining a component status of an operational component disposed within a flow passage of the flow duct utilizing the system are provided. In one exemplary aspect, the system includes at least two sensors that are disposed within the flow passage and configured to sense a characteristic of a fluid flowing therethrough. The sensors may be averaging sensors. Each sensor extends circumferentially about an axial centerline defined by the flow duct. The sensors are arranged in an overlapped arrangement. Particularly, the sensors extend circumferentially about the axial centerline such that the sensors physically overlap one another circumferentially. Additionally, the sensors may be disposed within the same or substantially the same plane axially. Signals generated by the sensors may be utilized to monitor and control the fluid and various operational components disposed within the flow passage.

Abstract: A monitoring and control system for a flow duct and a method for determining a component status of an operational component disposed within a flow passage of the flow duct utilizing the system are provided. In one exemplary aspect, the system includes at least two sensors that are disposed within the flow passage and configured to sense a characteristic of a fluid flowing therethrough. The sensors may be averaging sensors. Each sensor extends circumferentially about an axial centerline defined by the flow duct. The sensors are arranged in an overlapped arrangement. Particularly, the sensors extend circumferentially about the axial centerline such that the sensors physically overlap one another circumferentially. Additionally, the sensors may be disposed within the same or substantially the same plane axially. Signals generated by the sensors may be utilized to monitor and control the fluid and various operational components disposed within the flow passage.

Abstract: A fleet mission control system for a network of aerial vehicles including power thermal management systems is provided. According to examples of the disclosed technology a control system receives one or more mission objectives for a network of aircraft including two or more aerial vehicles. Each aerial vehicle includes a power-thermal management system. The control system receives system state information for the network of aircraft. The system state information includes PTMS state data. The control system determines a set of aircraft commands for the network of aircraft based on the one or more mission objectives and the PTMS state data, and generates an output signal based on the set of aircraft commands.

Abstract: The subject matter of the present disclosure is directed to a turbine engine having an adaptive prognostic health management control system that passively monitors stall margin reductions and applies corrective trims to a power management schedule of the engine to recover operability over time whilst maintaining a sufficient level of stall margin over the life cycle of the engine. The control system can adjust the power management schedule as needed to sustain a target stall margin, which allows for a more optimized and gradual performance to operability trade-off.

Abstract: A control system for active stability management of a compressor element of a turbine engine is provided. In one example aspect, the control system includes one or more computing devices configured to receive data indicative of an operating characteristic associated with the compressor element. For instance, the data can be received from a high frequency sensor operable to sense pressure at the compressor element. The computing devices are also configured to determine, by a machine-learned model, a stall margin remaining of the compressor element based at least in part on the received data. The machine-learned model is trained to recognize certain characteristics of the received data and associate the characteristics with a stall margin remaining of the compressor element. The computing devices are also configured to cause adjustment of one or more engine systems based at least in part on the determined stall margin remaining.

Abstract: The subject matter of the present disclosure is directed to a turbine engine having an adaptive prognostic health management control system that passively monitors stall margin reductions and applies corrective trims to a power management schedule of the engine to recover operability over time whilst maintaining a sufficient level of stall margin over the life cycle of the engine. The control system can adjust the power management schedule as needed to sustain a target stall margin, which allows for a more optimized and gradual performance to operability trade-off.

Abstract: A monitoring and control system for a flow duct and a method for determining a component status of an operational component disposed within a flow passage of the flow duct utilizing the system are provided. In one exemplary aspect, the system includes at least two sensors that are disposed within the flow passage and configured to sense a characteristic of a fluid flowing therethrough. The sensors may be averaging sensors. Each sensor extends circumferentially about an axial centerline defined by the flow duct. The sensors are arranged in an overlapped arrangement. Particularly, the sensors extend circumferentially about the axial centerline such that the sensors physically overlap one another circumferentially. Additionally, the sensors may be disposed within the same or substantially the same plane axially. Signals generated by the sensors may be utilized to monitor and control the fluid and various operational components disposed within the flow passage.

Abstract: A fleet mission control system for a network of aerial vehicles including power thermal management systems is provided. According to examples of the disclosed technology a control system receives one or more mission objectives for a network of aircraft including two or more aerial vehicles. Each aerial vehicle includes a power-thermal management system. The control system receives system state information for the network of aircraft. The system state information includes PTMS state data. The control system determines a set of aircraft commands for the network of aircraft based on the one or more mission objectives and the PTMS state data, and generates an output signal based on the set of aircraft commands.