A turbofan engine has an engine core including in flow series a compressor, a combustor and a turbine. The engine further has a fan located upstream of the engine core, has a supersonic intake for slowing down incoming air to subsonic velocities at an inlet to the fan formed by the intake, has a bypass duct surrounding the engine core, wherein the fan generates a core airflow to the engine core and a bypass airflow through the bypass duct, and has a mixer for mixing an exhaust gas flow exiting the engine core and bypass airflow exiting bypass duct. The engine further has a thrust nozzle rearwards of the mixer for discharging mixed flows, the thrust nozzle having a variable area throat. The engine further has a controller controlling the thrust produced by the engine over a range of flight operations including on-the-ground subsonic take-off and subsequent off-the-ground subsonic climb.

A turbofan engine has an engine core including in flow series a compressor, a combustor and a turbine. The engine further has a fan located upstream of the engine core, has a supersonic intake for slowing down incoming air to subsonic velocities at an inlet to the fan formed by the intake, has a bypass duct surrounding the engine core, wherein the fan generates a core airflow to the engine core and a bypass airflow through the bypass duct, and has a mixer for mixing an exhaust gas flow exiting the engine core and bypass airflow exiting bypass duct. The engine further has a thrust nozzle rearwards of the mixer for discharging mixed flows, the thrust nozzle having a variable area throat. The engine further has a controller controlling the thrust produced by the engine over a range of flight operations including on-the-ground subsonic take-off and subsequent off-the-ground subsonic climb.

The invention regards a gas turbine engine control system and a method for limiting turbine overspeed in case of a shaft failure. The control system includes: an overspeed protection system that activates an activation member in case a shaft failure is detected; a fuel limiting mechanism coupled with the activation member, wherein the fuel limiting mechanism is configured to limit the fuel supply to the gas turbine engine combustor if the activation member is activated; a variable stator vane mechanism which is configured to adjust variable stator vanes of a compressor of the gas turbine engine in their rotational position, the variable stator vanes having a closed position which blocks air flow through the compressor. A connecting fuel line connecting the fuel limiting mechanism and the variable stator vane mechanism is provided, wherein upon activation of the activation member the fuel limiting mechanism pressurizes the connecting fuel line, thereby activating the variable stator vane mechanism to move at least one row of the variable stator vanes into the closed position.

The invention regards a gas turbine engine control system and a method for limiting turbine overspeed in case of a shaft failure. The control system includes: an overspeed protection system that activates an activation member in case a shaft failure is detected; a fuel limiting mechanism coupled with the activation member, wherein the fuel limiting mechanism is configured to limit the fuel supply to the gas turbine engine combustor if the activation member is activated; a variable stator vane mechanism which is configured to adjust variable stator vanes of a compressor of the gas turbine engine in their rotational position, the variable stator vanes having a closed position which blocks air flow through the compressor. A connecting fuel line connecting the fuel limiting mechanism and the variable stator vane mechanism is provided, wherein upon activation of the activation member the fuel limiting mechanism pressurizes the connecting fuel line, thereby activating the variable stator vane mechanism to move at least one row of the variable stator vanes into the closed position.

Methods and systems for detecting and responding to an engine disturbance are described. The method comprises monitoring a rate of change of a combustor pressure of an engine, detecting an engine disturbance when the rate of change of the combustor pressure falls below an event detection threshold, initiating an engine recovery sequence in response to detecting the engine disturbance, confirming a surge event when the rate of change of the combustor pressure increases above a surge confirmation threshold within a flameout confirmation time period after having crossed the event detection threshold, applying a surge recovery sequence in response to confirming the surge event, confirming a flameout event when the flameout confirmation time period expires and the rate of change of the combustor pressure remains below the surge confirmation threshold after having crossed the event detection threshold, and applying a flameout recovery sequence in response to confirming the flameout event.

Methods and systems for detecting and responding to an engine disturbance are described. The method comprises monitoring a rate of change of a combustor pressure of an engine, detecting an engine disturbance when the rate of change of the combustor pressure falls below an event detection threshold, initiating an engine recovery sequence in response to detecting the engine disturbance, confirming a surge event when the rate of change of the combustor pressure increases above a surge confirmation threshold within a flameout confirmation time period after having crossed the event detection threshold, applying a surge recovery sequence in response to confirming the surge event, confirming a flameout event when the flameout confirmation time period expires and the rate of change of the combustor pressure remains below the surge confirmation threshold after having crossed the event detection threshold, and applying a flameout recovery sequence in response to confirming the flameout event.

A method of controlling a combustion system of a gas turbine engine which has a combustor with a primary combustion zone, of which a condition in the primary combustion zone is defined by a primary zone control parameter. The method includes controlling the primary zone control parameter to be substantially constant value over a range of values of compressor inlet air temperature.

A method of controlling a combustion system of a gas turbine engine which has a combustor with a primary combustion zone, of which a condition in the primary combustion zone is defined by a primary zone control parameter. The method includes controlling the primary zone control parameter to be substantially constant value over a range of values of compressor inlet air temperature.

The invention concerns a method for monitoring the operating state of a system for positioning variable-geometry members (18) of a turbomachine (10), the members (18) being configured to travel over an operating area comprising a first position P1 and a second position P2, the method comprising the steps of: -(E23) determining a first pivoting speed V1 from the first position P1 to the second position P2; -(E25) determining a second pivoting speed from the second position P2 to the first position P1; and -(E26) determining an anomaly in the operation of the system for positioning the members (18) if the first speed V1 is lower than a first determined speed threshold and/or if the second speed V2 is lower than a second determined speed threshold.

The invention concerns a method for monitoring the operating state of a system for positioning variable-geometry members (18) of a turbomachine (10), the members (18) being configured to travel over an operating area comprising a first position P1 and a second position P2, the method comprising the steps of: -(E23) determining a first pivoting speed V1 from the first position P1 to the second position P2; -(E25) determining a second pivoting speed from the second position P2 to the first position P1; and -(E26) determining an anomaly in the operation of the system for positioning the members (18) if the first speed V1 is lower than a first determined speed threshold and/or if the second speed V2 is lower than a second determined speed threshold.