A feedback device for use in a gas turbine engine, and methods and systems for controlling a pitch for an aircraft-bladed rotor, are provided. The feedback device is composed of a circular disk and a plurality of position markers. The circular disk is coupled to rotate with a rotor of the gas turbine engine, to move along a longitudinal axis of the rotor, and has first and second opposing faces defining a root surface that extends between and circumscribes the first and second faces. The plurality of position markers extend radially from the root surface and are circumferentially spaced around the circular disk. The position markers have a top surface elevated with respect to the root surface and opposing first and second side surfaces. The side surfaces of the position markers have a curved concave profile extending toward the root surface.

An electronic control system (30) for a turbopropeller engine (1) having a gas turbine (2, 4, 5, 6) and a propeller (7), coupled to the gas turbine, the control system (10) having a propeller control unit (14) and a turbine control unit (15) to jointly control engine power output based on an input request (PLA), wherein the propeller control unit (14) has a first reference generator (16), to determine a reference propeller speed (N.sub.pref) based on the input request (PLA), and a first regulator (19), to regulate a propeller speed (N.sub.p). The propeller control unit (14) has a reference correction stage (31) to apply a correction to the reference propeller speed (N.sub.pref) and generate thereby a corrected reference propeller speed (I), and the first regulator (19) regulates the propeller speed (N.sub.p) based on the corrected reference propeller speed (I) to achieve optimized efficiency.

An electronic control system (30) for a turbopropeller engine (1) having a gas turbine (2, 4, 5, 6) and a propeller (7), coupled to the gas turbine, the control system (10) having a propeller control unit (14) and a turbine control unit (15) to jointly control engine power output based on an input request (PLA), wherein the propeller control unit (14) has a first reference generator (16), to determine a reference propeller speed (N.sub.pref) based on the input request (PLA), and a first regulator (19), to regulate a propeller speed (N.sub.p). The propeller control unit (14) has a reference correction stage (31) to apply a correction to the reference propeller speed (N.sub.pref) and generate thereby a corrected reference propeller speed (I), and the first regulator (19) regulates the propeller speed (N.sub.p) based on the corrected reference propeller speed (I) to achieve optimized efficiency.

A system is described that includes a turbine engine including an engine fan including one or more variable-pitch blades driven by a shaft, which rotates at a rotational speed which depends on a pitch of the one or more variable-pitch blades of the engine fan. The system further includes a generator configured to produce alternating-current (AC) electricity at a particular frequency relative to the rotational speed of the shaft. The system also includes a propulsor, which includes a propulsor motor and a propulsor fan. The propulsor motor is configured to drive, based on the AC electricity produced by the generator, the propulsor fan. The system includes a controller configured to control the particular frequency of the AC electricity by at least controlling the pitch of the one or more variable-pitch blades of the engine fan and thereby the rotational speed of the generator.

A system is described that includes a turbine engine including an engine fan including one or more variable-pitch blades driven by a shaft, which rotates at a rotational speed which depends on a pitch of the one or more variable-pitch blades of the engine fan. The system further includes a generator configured to produce alternating-current (AC) electricity at a particular frequency relative to the rotational speed of the shaft. The system also includes a propulsor, which includes a propulsor motor and a propulsor fan. The propulsor motor is configured to drive, based on the AC electricity produced by the generator, the propulsor fan. The system includes a controller configured to control the particular frequency of the AC electricity by at least controlling the pitch of the one or more variable-pitch blades of the engine fan and thereby the rotational speed of the generator.

A control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4), is provided with: a control unit (12) to control a forward operating mode or a reverse operating mode of the gas turbine engine (1); and a supervising unit (14), operatively coupled to the control unit (12), to receive an input signal (PLA) indicative of a forward, or reverse, power request and to cause the control unit (12) to control the forward, or reverse, operating mode based on the input signal (PLA). The supervising unit (14) has an enabling stage (20) to enable a transition between the forward and reverse operating modes based on a check that a safety condition is satisfied.

A control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4), is provided with: a control unit (12) to control a forward operating mode or a reverse operating mode of the gas turbine engine (1); and a supervising unit (14), operatively coupled to the control unit (12), to receive an input signal (PLA) indicative of a forward, or reverse, power request and to cause the control unit (12) to control the forward, or reverse, operating mode based on the input signal (PLA). The supervising unit (14) has an enabling stage (20) to enable a transition between the forward and reverse operating modes based on a check that a safety condition is satisfied.

A gas turbine engine including a core having in serial flow order a compressor, a combustor, and a turbine—the compressor, combustor, and turbine together defining a core air flowpath. The gas turbine engine additionally includes a fan section mechanically coupled to the core, the fan section including a plurality of fan blades, and each of the plurality fan blades defining a pitch axis. An actuation device is operable with the plurality fan blades for rotating the plurality fan blades about their respective pitch axes, the actuation device including an actuator located outward of the core air flowpath to, e.g., simplify the gas turbine engine.

A gas turbine engine including a core having in serial flow order a compressor, a combustor, and a turbine—the compressor, combustor, and turbine together defining a core air flowpath. The gas turbine engine additionally includes a fan section mechanically coupled to the core, the fan section including a plurality of fan blades, and each of the plurality fan blades defining a pitch axis. An actuation device is operable with the plurality fan blades for rotating the plurality fan blades about their respective pitch axes, the actuation device including an actuator located outward of the core air flowpath to, e.g., simplify the gas turbine engine.

Systems and methods are described for governing the speed of a propeller on a propeller-based engine in an aircraft. The method comprises obtaining a synthesized or estimated blade angle for the propeller of the engine, determining one or more gain for a controller of the propeller based on the synthesized or estimated blade angle and one or more engine or aircraft parameter, determining a difference between a reference propeller speed and an actual propeller speed, applying the one or more gain to the difference via the controller in order to generate a command signal for controlling the propeller, and governing the propeller of the engine using the command signal.