According to one contemplated embodiment of the rocket engine invention, water is first pumped from a water tank through a rocket nozzle cooling heat exchanger wherein it is evaporated into said superheated steam. A generator supplies electricity to an electrolyzer that electrolyzes superheated steam into gaseous hydrogen and gaseous oxygen. The gaseous hydrogen and gaseous oxygen is employed for forming an annular curtain of secondary combustion in a divergent rocket engine. The secondary combustion gas surrounds a central thrust of combustion gas produced in an upstream combustion chamber by a primary injection of hydrogen/oxygen supplied from a liquid hydrogen tank and liquid oxygen tank. The rocket liquid hydrogen tank and liquid oxygen tank are pressurized by gaseous hydrogen and gaseous oxygen generated by the electrolyzer.

Method for controlling a first, a second and a third variable of a turbomachine as a function of a first, a second and a third control quantity of a turbomachine which can each be saturated as a function of the operating parameters of the turbomachine.

The method comprises a first multivariable correction (120) delivering a first value for the three control quantities, a selection (130) of the first control quantity to be delivered as a function of a minimum value, of a maximum value and of the value determined by the first correction, a second multivariable correction (140) delivering a second value for the second and third control quantities, and a selection (150) of the values of the second and third control quantities to be delivered in the values determined during the first correction and those determined during the second correction.

A system includes a thermal engine operatively connected to drive a propeller. An electric motor is operatively connected to the thermal engine to drive the propeller together with the thermal engine. An external input system is configured to accept input and output a thrust command. A protection function module is configured to enforce limits on the thermal engine, electric motor, and propeller. A low select module is operatively connected to receive input from the external input system and form the protection function module and to output the lower of input from the protection function module and external input system to the thermal engine, the electric motor, and the propeller.

An aspect includes a variable cycle system of a gas turbine engine. The variable cycle system includes an actuation system, an electric component, and a controller. The actuation system is configured to adjust a variable cycle of turbomachinery of the gas turbine engine. The electric component is operable to provide a shaft power supply or a load corresponding respectively to an adjustment of the turbomachinery. The controller is operable to adjust an output of either or both of the actuation system and the electric component for separate control of thrust and cycle responses.

An electronic control system (30) for a turbopropeller engine (12) having a gas turbine (20) and a propeller assembly (13) coupled to the gas turbine (20), controls propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle (β) of propeller blades (2) of the propeller assembly (13). The control system (30) envisages: a propeller speed regulator (39), receiving at its input a propeller speed error (ep), indicative of a difference between a propeller speed measure (Nr) and a propeller speed demand (Nrref), and generating at its output, based on the propeller speed error (ep), a first control quantity (Outi); a propeller pitch regulator (42), receiving at its input a propeller pitch error (ep), indicative of a difference between a propeller pitch demand ( ) and a pitch position measure (β), and generating at its output, based on the propeller pitch error (ep), a first control quantity (Out2); and a priority selection stage (45), configured to implement a priority selection between the first and the second control quantities, for providing at the output the driving quantity (IP), based on the priority selection between the first and the second control quantities.

An electronic control system (30) for a turbopropeller engine (12) having a gas turbine (20) and a propeller assembly (13) coupled to the gas turbine (20), controls propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle (β) of propeller blades (2) of the propeller assembly (13). The control system (30) envisages: a propeller speed regulator (39), receiving at its input a propeller speed error (ep), indicative of a difference between a propeller speed measure (Nr) and a propeller speed demand (Nrref), and generating at its output, based on the propeller speed error (ep), a first control quantity (Outi); a propeller pitch regulator (42), receiving at its input a propeller pitch error (ep), indicative of a difference between a propeller pitch demand ( ) and a pitch position measure (β), and generating at its output, based on the propeller pitch error (ep), a first control quantity (Out2); and a priority selection stage (45), configured to implement a priority selection between the first and the second control quantities, for providing at the output the driving quantity (IP), based on the priority selection between the first and the second control quantities.

A fan assembly for a gas turbine engine includes a fan disk, a trunnion, an actuation device, a fan blade, and a counterweight assembly. The trunnion is mounted to the fan disk. The actuation device is operably coupled to the trunnion. The fan blade is rotatably attached to the fan disk. The counterweight assembly includes a link arm, a lever arm, a hinge, and a counterweight. The link arm is connected to the trunnion, to the actuation device, or to both. The link arm is configured to drive rotation of the trunnion relative to the fan disk. The hinge is pivotably connected to the lever arm. The lever arm is connected to the link arm and is disposed to rotate about a connection point of the lever arm and the hinge. The counterweight is mounted to the lever arm at a location spaced from the hinge.

A fan assembly for a gas turbine engine includes a fan disk, a trunnion, an actuation device, a fan blade, and a counterweight assembly. The trunnion is mounted to the fan disk. The actuation device is operably coupled to the trunnion. The fan blade is rotatably attached to the fan disk. The counterweight assembly includes a link arm, a lever arm, a hinge, and a counterweight. The link arm is connected to the trunnion, to the actuation device, or to both. The link arm is configured to drive rotation of the trunnion relative to the fan disk. The hinge is pivotably connected to the lever arm. The lever arm is connected to the link arm and is disposed to rotate about a connection point of the lever arm and the hinge. The counterweight is mounted to the lever arm at a location spaced from the hinge.

A gas turbine engine includes a fan section, a compressor section, and a turbine section. The fan section has a plurality of vane assemblies spaced circumferentially about an engine axis. The vane assemblies each include an airfoil extending between a leading edge and a trailing edge, a control rod extending through the airfoil, and a mechanism driven by the control rod to change the shape of the airfoil. A vane system for a gas turbine engine is also disclosed.

A gas turbine engine includes a fan section, a compressor section, and a turbine section. The fan section has a plurality of vane assemblies spaced circumferentially about an engine axis. The vane assemblies each include an airfoil extending between a leading edge and a trailing edge, a control rod extending through the airfoil, and a mechanism driven by the control rod to change the shape of the airfoil. A vane system for a gas turbine engine is also disclosed.