A method of operating a gas turbine engine in a multi-engine aircraft, the gas turbine engine having an engine shaft mounted for rotation in a bearing and a gearbox connected to the engine shaft for torque transmission therebetween, includes axially preloading the bearing using an axially biasing element disposed between the gas turbine engine and the gearbox. The axially biasing element reacts against the gearbox to exert an axial preload force on the bearing and the engine shaft of the gas turbine engine.

A power management system for a multi engine rotorcraft having a main rotor system with a main rotor speed. The power management system includes a first engine that provides a first power input to the main rotor system. A second engine selectively provides a second power input to the main rotor system. The second engine has at least a zero power input state and a positive power input state. A power anticipation system is configured to provide the first engine with a power adjustment signal in anticipation of a power input state change of the second engine during flight. The power adjustment signal causes the first engine to adjust the first power input to maintain the main rotor speed within a predetermined rotor speed threshold range during the power input state change of the second engine.

A propulsion system for an aircraft includes at least two gas turbine engines and at least one auxiliary propulsion fan. The at least one auxiliary propulsion fan is configured to selectively receive a motive force from either or both of the at least two gas turbine engines through at least one shaft operatively coupled to the at least one auxiliary propulsion fan.

A method for operation of a hybrid propulsion system is provided that includes providing a hybrid propulsion system including a gas turbine engine, an electrical system, and a controller configured to cause the gas turbine engine to produce a first mechanical power output and to cause the electrical system to produce a second mechanical power output. The method further includes causing the gas turbine engine to produce the first mechanical power output and causing the electrical system to produce the second mechanical power output, which causes a drive shaft of the gas turbine engine to rotate. The method further includes decreasing production of the first mechanical power output when a combination of the first mechanical power output and the second mechanical power output for take-off or climb is a predetermined percentage of a predetermined parameter of the gas turbine engine.

A compressed air energy storage power generation device includes motors, compressors that compress air, an accumulator tank that accumulates compressed air, expanders to driven by the compressed air supplied from the accumulator tank, generators, and a control device that controls driving of the motors. The control device includes a power supply command receiver that receives a power supply command, a priority setting unit that sets priority to the motors so that the motor whose elapsed time from stop is shorter has higher priority, a number-of-units determination unit that determines the number of the motors to be driven on the basis of an amount of input power indicated by the power supply command, and a drive unit that drives the motors in the descending order of the priority until the number of the driven motors becomes equal to the number of motors to be driven determined by the number-of-units determination unit.

A gas turbine combined cycle (GTCC) power generation plant (100) equipped with a control unit which performs a load reduction following operation with respect to a fuel adjustment valve (Vd), a main steam valve (V1), and a bypass valve (V4), wherein, when a load reduction request for reducing a GTCC load target value has been input in a closed bypass operation, the degree of opening of the fuel adjustment valve (Vd) is reduced in accordance with the target value while the main steam valve (V1) is in an open state, and the bypass valve (V4) is placed in an open state, after which the bypass valve (V4) is placed in the closed state when the GTCC load reaches the target value.

There is provided a system and a method for operating a multi-engine rotorcraft. When the rotorcraft is cruising in an asymmetric operating regime (AOR) at least one engine is an active engine and is operated in an active mode to provide motive power to the rotorcraft and at least one second engine is a standby engine and is operated in a standby mode to provide substantially no motive power to the rotorcraft, at least one of a power level of the at least one second engine is increased and at least one variable geometry mechanism of the at least one second engine is moved to shed any ice accumulation on the at least one second engine.

Aircraft, engine electronic controller systems, and methods for controlling thrust in a no dwell zone are provided. In one example, an aircraft includes a first engine that includes a first compressor fan rotating at a first speed and a second engine that includes a second compressor fan rotating at a second speed. First and second engine electronic controllers receive engine thrust commands and are in communication with the first and second engines, respectively. When the engine thrust commands correspond to an engine response within a no dwell zone, the first engine electronic controller directs the first engine to have the first speed at or below a compressor fan speed lower boundary and the second engine electronic controller directs the second engine to have the second speed at or above the compressor fan speed upper boundary to produce an overall average thrust within the no dwell zone.

Aircraft autothrottle system, having a motor to impart rotational movement to a shaft extending from the motor. An actuator is connected to the shaft and to an attachment end of a throttle lever having a control end, opposite the attachment end. The actuator has bearings to apply thrust to a longitudinal surface of the shaft such that the actuator is translated longitudinally along the shaft surface in response to motor-imparted rotation of the shaft. The shaft surface being smoothly continuous and longitudinally unbroken along its elongation to allow the actuator to longitudinally slip along the shaft irrespective of any shaft rotation by the motor when the thrust force exceeds a linear force manually applied at the throttle lever. An electronic controller for the motor to move the throttle lever so the motor moves the actuator assembly along the shaft based on an engine parameter monitored by the controller.

The present disclosure provides methods and systems for operating a rotorcraft comprising a plurality of engines configured to provide motive power to the rotorcraft. A request to enter into an asymmetric operating regime (AOR), in which at least one first engine of the plurality of engines is an active engine and is operated in an active mode to provide motive power to the rotorcraft and at least one second engine of the plurality of engines is a standby engine and is operated in a standby mode to provide substantially no motive power to the rotorcraft, is obtained. A power capability of the active engine of the rotorcraft is determined. The power capability is compared to a current power demand for the rotorcraft. When the current power demand is greater than the power capability of the active engine, a standby-engine power output of the standby engine of the rotorcraft is reduced, and the reduction in the standby-engine power output is compensated for by adjusting an active-engine power output of the active engine and/or at least one flight control of the rotorcraft.