An inlet door state control system for an auxiliary power unit (APU) includes an inlet door configured to allow air into an inlet of the APU. The system also includes an actuator configured to open the inlet door. The system also includes an APU threshold switch connected to the actuator, the APU threshold switch configured to automatically change from an open position to a closed position when a predetermined APU operating condition is met. In the system, the actuator opens the inlet door when the APU threshold switch is in the closed position.

Methods and systems for operating a gas turbine engine in a multi-engine aircraft are described. The method comprises operating the gas turbine engine in a standby mode to provide substantially no motive power to the aircraft when another engine of the multi-engine aircraft is operated in an active mode to provide motive power to the aircraft, transitioning the gas turbine engine from the standby mode to the non-standby mode, and applying pulse width modulation to an air switching system of the gas turbine engine while transitioning the gas turbine engine from the standby mode to the non-standby mode.

A control system for a gas turbine engine including a power turbine is disclosed. The control system may include a control module to receive engine operating goals and an estimated current engine state, wherein the estimated current engine state is produced by a model-based estimation module using a bandwidth signal produced by an adaptation logic module. The control module is operative to determine fuel flow, inlet guide vane schedules and stability bleed schedules based at least in part on the received engine operating goals and the estimated current engine state, and to send signals to a gas generator of the gas turbine engine in order to control the gas generator according to the determined fuel flow, inlet guide vane schedules and stability bleed schedules.

A turbine engine including: a rotor supporting a blade and guided by means of bearings; a control system for controlling the blade, which is solidly connected to the rotor and which includes an actuator driven by energy, the control system being disposed axially upstream of the bearings; and a device for transferring the energy, disposed axially between the bearings and including a stationary member and a moving member. The rotor includes a support ring supporting the blade and a shaft having a frustoconical portion and a cylindrical portion on which the bearings and the moving member are mounted, the frustoconical portion extending about the cylindrical portion.

To control an engine shutdown in an aircraft, a control system includes a fuel supply shut-off member, a control member with a set of switches, a first switch on an electrical power supply link of the fuel supply shut-off member and second switches connected to avionics of the aircraft, the set of switches switching position on an engine shutdown command. An engine shutdown confirmation unit includes a third switch on the electrical power supply link, the third switch in open position by default. The engine shutdown confirmation unit includes electronic circuitry configured to switch the third switch over to closed position when a predefined quantity Q of switches of the control member switches position within a sliding window of predefined duration and, otherwise, keeps the third switch in open position. Thus, it is ensured that the engine shutdown is intentional.

A turbine engine including: a rotor having at least one variable-pitch blade which is guided to rotate on bearings relative to a fixed structure; a system for controlling the pitch of the at least one blade, the control system being rigidly secured to the rotor and including a first actuator driven by energy, and the control system further being disposed axially upstream of the bearings; a device for transferring the energy, which is disposed axially between the bearings, the transfer device including a stationary element and a mobile element; wherein the rotor is annular and delimits an inner space which is open towards the upstream side and inside of which the control system is disposed.

A fuel supply control device is provided in which a parallel flow path of an orifice and a pressurizing valve is used as a complex pressurizing valve for a fuel supply amount, and which controls a fuel supply pump on the basis of a pressure difference before and after the complex pressurizing valve that has been detected by a pressure difference meter. When the rotational speed of the fuel supply pump is below a predetermined threshold value, the fuel supply pump is controlled on the basis of a first fuel measurement amount, and the fuel supply pump is controlled on the basis of a second fuel measurement amount.

A controller may use energy packets to control a prime mover of a machine. The controller may include an energy packet measurement control to calculate energy packets, perform post-processing actions on the energy packets to generate processed energy packets, and convert the processed energy packets into a fuel valve reference. Post-processing may include a calibration correction to remove measurement artifacts.

A gas turbine engine includes a generator that is configured to be driven by a turbine section, an electric motor that is configured to receive at least a portion of electric power from the generator, a gearbox that is mechanically coupled to both the electric motor and the generator, and a control system that has an operational amplifier that is configured to synchronize operation of the electric motor and the generator. The operational amplifier electrically couples the electric motor to the generator and is configured to define an electrical gain that matches a mechanical gain that is defined by the gearbox.

A turbine engine including: a rotor having at least one variable-pitch blade which is guided to rotate on bearings relative to a fixed structure; a system for controlling the pitch of the at least one blade, the control system being rigidly secured to the rotor and including a first actuator driven by energy, and the control system further being disposed axially upstream of the bearings; a device for transferring the energy, which is disposed axially between the bearings, the transfer device including a stationary element and a mobile element; wherein the rotor is annular and delimits an inner space which is open towards the upstream side and inside of which the control system is disposed.