There is provided a method and system for operating a turboprop engine of an aircraft. When a resulting value for Ng is between at least one upper limit and at least one lower limit, the output power is governed as a function of the target power. When the resulting value for Ng is on or outside of the at least one upper limit and the at least one lower limit, the output power is governed as a function of the maximum Ng and the minimum Ng.

A system includes a gas turbine engine having a low speed spool, a high speed spool, and a combustor. The system also includes a low spool motor configured to augment rotational power of the low speed spool. The system further includes a controller configured to cause fuel flow. The controller is operable to control the low spool motor to drive rotation of the low speed spool responsive to a thrust command while the controller does not command fuel flow to the combustor.

The present disclosure provides methods and systems for operating a multi-engine rotorcraft. The method comprises driving a rotor of the rotorcraft with a first engine while a second engine is de-clutched from a transmission clutch system that couples the rotor and the second engine, instructing the second engine to accelerate to a re-clutching speed, and controlling an output shaft speed of the second engine during acceleration of the second engine to the re-clutching speed by applying a damping function to a speed control loop of the second engine.

Methods and systems for operating an aircraft powerplant are described herein. One or more powerplant or aircraft parameters indicative of one or more conditions at landing or during an approach to landing are obtained. A reverse thrust rating is determined based on the one or more powerplant or aircraft parameters. Reverse thrust of the powerplant is controlled based on the reverse thrust rating when reverse thrust is requested.

A regulator device for regulating a speed of rotation, of a shaft of a gas generator of at least one turboshaft engine of a rotorcraft. The rotorcraft has at least one main rotor for regulating at least lift and/or propulsion for said rotorcraft in the air; a control member for controlling a collective pitch of the blades of said at least one main rotor, said control member serving to generate a control setpoint for said collective pitch; at least one turboshaft engine suitable for driving rotation of said at least one main rotor, said at least one engine producing, at least temporarily, a drive torque that is transmitted to said at least one main rotor; and measurement means for taking at each instant a measurement of said drive torque transmitted by said at least one engine to said at least one main rotor.

Systems and methods for starting an engine on an aircraft are provided. One example aspect of the present disclosure is directed to an integrated starter for starting an engine on an aircraft. The integrated starter includes an air turbine starter. The integrated starter includes a starter air valve integrated with the air turbine starter. The integrated starter includes a controller configured to control the starter air valve. The starter air valve can be movable between a first position and at least a second position to regulate the flow of fluid into the air turbine starter. An output torque of the air turbine starter can be dependent at least in part on the flow of fluid into the air turbine starter.

Hybrid electric systems and methods therefore are provided. In one exemplary aspect, a hybrid electric system includes an engine, an electric machine operatively coupled thereto and configured to generate electrical power when driven by the engine. One or more electrical loads are electrically connectable with the electric machine. An engine controller of the engine receives load state data indicative of electrical loads that anticipate electrically disconnecting from or electrically connecting to the electric machine at a predetermined time. In this way, the engine controller can anticipate electrical load changes and the engine can be controlled to adjust its torque output in anticipation of the electrical load change. In another exemplary aspect, a hybrid electric system is provided that includes features for nearly instantaneously reacting to load changes on the engine based on load state data received from feed forward inputs of the electrical system of the hybrid electric system.

Systems and methods to pump fracturing fluid into a wellhead may include a gas turbine engine including a compressor turbine shaft connected to a compressor, and a power turbine output shaft connected to a power turbine. The compressor turbine shaft and the power turbine output shaft may be rotatable at different rotational speeds. The systems may also include a transmission including a transmission input shaft connected to the power turbine output shaft and a transmission output shaft connected to a hydraulic fracturing pump. The systems may also include a fracturing unit controller configured to control one or more of the rotational speeds of the compressor turbine shaft, the power turbine output shaft, or the transmission output shaft based at least in part on target signals and fluid flow signals indicative of one or more of pressure or flow rate associated with fracturing fluid pumped into the wellhead.

A rotor dynamics adjustment system includes a rotor system with at least one compressor section and at least one turbine section operably coupled to a shaft. The rotor dynamics adjustment system also includes one or more rotor system sensors configured to collect a plurality of sensor data from the rotor system, an electric motor operably coupled to the rotor system, and a controller. The controller is operable to monitor the one or more rotor system sensors while the rotor system is rotating. A dynamic motion of the rotor system is characterized based on the sensor data from the one or more rotor system sensors. A damping correction torque is determined to diminish the dynamic motion of the rotor system. The electric motor is commanded to apply the damping correction torque to the rotor system.

Systems and methods to pump fracturing fluid into a wellhead may include a gas turbine engine including a compressor turbine shaft connected to a compressor, and a power turbine output shaft connected to a power turbine. The compressor turbine shaft and the power turbine output shaft may be rotatable at different rotational speeds. The systems may also include a transmission including a transmission input shaft connected to the power turbine output shaft and a transmission output shaft connected to a hydraulic fracturing pump. The systems may also include a fracturing unit controller configured to control one or more of the rotational speeds of the compressor turbine shaft, the power turbine output shaft, or the transmission output shaft based at least in part on target signals and fluid flow signals indicative of one or more of pressure or flow rate associated with fracturing fluid pumped into the wellhead.