A gas turbine engine has a fan case exit and an inner core housing exit. At least one of the exits is provided with a fiber optic sensing unit. The fiber optic sensing unit includes a fiber optic sensing member surrounding a circumference of the at least one of the exits. A control is programmed to calculate a nozzle area at the at least one of the exits based upon the displacement of the fiber optic sensing member. The calculated nozzle area is utilized to update nozzle area information at an electronic engine controller for the engine, and the electronic engine controller is programmed to control at least one associated component on a gas turbine engine based upon the updated nozzle area. A method is also disclosed.

An aircraft propulsion system includes a gas turbine engine; a generator; a storage battery; a motor which drives a rotor, using at least one of the electric power which is output from the generator and the electric power which is output from the storage battery; a detection unit which detects the number of revolutions of the engine shaft; an engine control unit which controls at least a fuel flow rate of the gas turbine engine; and a generator control unit which controls the operation of the generator. When the number of revolutions satisfies a predetermined condition, at least the generator control unit executes a control for reducing a sudden change in the number of revolutions.

A method of actively controlling torsional resonance of a rotating shaft of an engine is provided. The shaft has a rotational velocity characterised by a low frequency, rotational velocity term and a high frequency, oscillatory term superimposed on the low frequency term, the oscillatory term being caused by torsional resonance. The method including: measuring the rotational velocity of the shaft; extracting the oscillatory term from the measured rotational velocity; and on the basis of the extracted oscillatory term, applying a torque component to the shaft, the torque component being modulated at the same frequency as the torsional resonance to counteract the torsional resonance.

A method for operating a hybrid-electric gas turbine engine is provided. The method includes: receiving data indicative of an actual rotational speed of a shaft; calculating an error between the actual rotational speed of the shaft and a commanded rotational speed of the shaft; providing the calculated error to a fuel flow control circuit operable with a fuel delivery system of the hybrid-electric propulsion engine; providing the calculated error to an electric machine control circuit operable with an electric machine of the hybrid-electric propulsion engine, the electric machine drivingly coupled to the shaft; and modifying a torque on the shaft from the electric machine with the electric machine control circuit based on the calculated error.

A system includes a controller configured to monitor a fuel system supplying fuel to a gas turbine engine. The system also includes an electric propulsion system controlled by the controller. The electric propulsion system is configured as a variable load, which is supplied rotational energy by the engine. The controller is configured to dynamically control a magnitude of the variable load to adjust rotational speed of the gas turbine engine during a fixed level of fuel supply to the gas turbine engine. The electric propulsion system may include an electric generator and a plurality of propulsor motor(s) rotating a propulsor to provide thrust and/or lift to a vehicle such as an aircraft. The electric generator may be rotationally driven with the gas turbine engine to output electric power. The electric power is supplied to the propulsor motor(s) to rotate the propulsor to provide thrust and/or lift of the vehicle.

A system includes a controller configured to monitor a fuel system supplying fuel to a gas turbine engine. The system also includes an electric propulsion system controlled by the controller. The electric propulsion system is configured as a variable load, which is supplied rotational energy by the engine. The controller is configured to dynamically control a magnitude of the variable load to adjust rotational speed of the gas turbine engine during a fixed level of fuel supply to the gas turbine engine. The electric propulsion system may include an electric generator and a plurality of propulsor motor(s) rotating a propulsor to provide thrust and/or lift to a vehicle such as an aircraft. The electric generator may be rotationally driven with the gas turbine engine to output electric power. The electric power is supplied to the propulsor motor(s) to rotate the propulsor to provide thrust and/or lift of the vehicle.

The present disclosure is directed to a method of control of a gas turbine engine comprising a fan section coupled to a low turbine together defining a low spool, an intermediate compressor coupled to an intermediate turbine together defining an intermediate spool, and a high compressor coupled to a high turbine together defining a high spool. The method includes providing an intermediate spool speed to low spool speed characteristic curve to a controller; providing a commanded power output to the controller; providing one or more of an environmental condition to the controller; determining, via the controller, a commanded fuel flow rate; determining, via the controller, a commanded intermediate compressor loading; and generating an actual power output of the engine, wherein the actual power output is one or more of an actual low spool speed, an actual intermediate spool speed, an actual high spool speed, and an actual engine pressure ratio.

Methods and systems for calibrating an engine having a rotating shaft are provided. Readings from a plurality of speed sensors provided in one of a plurality of configurations about the shaft are obtained over a plurality of rotations of the shaft, the readings indicative of the passage of position markers and associated with a first precision level. A parameter indicative of relative spacing between the plurality of speed sensors is determined by applying a statistical algorithm to the readings, the parameter being associated with a second precision level higher than the first precision level. The parameter is compared to reference parameters associated with the plurality of configurations to identify an actual speed sensor configuration from amongst the plurality of configurations. The engine is calibrated based on the actual speed sensor configuration.

Methods and systems for calibrating an engine having a rotating shaft are provided. Readings from a plurality of speed sensors provided in one of a plurality of configurations about the shaft are obtained over a plurality of rotations of the shaft, the readings indicative of the passage of position markers and associated with a first precision level. A parameter indicative of relative spacing between the plurality of speed sensors is determined by applying a statistical algorithm to the readings, the parameter being associated with a second precision level higher than the first precision level. The parameter is compared to reference parameters associated with the plurality of configurations to identify an actual speed sensor configuration from amongst the plurality of configurations. The engine is calibrated based on the actual speed sensor configuration.

A method for selectively operating a combustor head end assembly is provided. The combustor head end assembly includes a plurality of bundled tube fuel nozzles. The method includes opening a first fuel circuit of a plurality of fuel circuits. The first fuel circuit of the plurality of fuel circuits is fluidly coupled to a first nozzle group, and the first nozzle group includes one bundled tube fuel nozzle of the plurality of bundled tube fuel nozzles. The method further includes adjusting an airflow received by the plurality of bundled tube fuel nozzles in response to opening the first fuel circuit of the plurality of fuel circuits. The airflow is adjusted based on an emissions output requirement corresponding with the first nozzle group. The method also includes firing the first nozzle group.