An aspect includes a hybrid gas turbine engine system of a hybrid electric aircraft. The hybrid gas turbine engine system includes a gas turbine engine, an electric motor operable to perform an electric taxiing of the hybrid electric aircraft, and a controller. The controller is operable to prevent fuel flow to the gas turbine engine during at least a portion of the electric taxiing and monitor for a powered warm-up request during the electric taxiing. A powered warm-up state of the gas turbine engine is initiated based on detecting the powered warm-up request. The powered warm-up state adds heat to one or more components of the gas turbine engine prior to transitioning to a takeoff power state. The gas turbine engine transitions from the powered warm-up state to the takeoff power state after reaching a target temperature of the one or more components in the powered warm-up state.

An aspect includes a hybrid gas turbine engine system of a hybrid electric aircraft. The hybrid gas turbine engine system includes a gas turbine engine, an electric motor operable to perform an electric taxiing of the hybrid electric aircraft, and a controller. The controller is operable to prevent fuel flow to the gas turbine engine during at least a portion of the electric taxiing and monitor for a powered warm-up request during the electric taxiing. A powered warm-up state of the gas turbine engine is initiated based on detecting the powered warm-up request. The powered warm-up state adds heat to one or more components of the gas turbine engine prior to transitioning to a takeoff power state. The gas turbine engine transitions from the powered warm-up state to the takeoff power state after reaching a target temperature of the one or more components in the powered warm-up state.

A gas turbine system can estimate an amount of compressed air supplied to a combustor and limit a fuel amount according to the estimated compressed air amount. A control apparatus of the system includes a sensing unit to measure the turbine rotor speed; a compressed air amount estimation unit to estimate a change rate M.sub.R of an amount of compressed air produced by the compressor and supplied to the combustor, based on the measured turbine rotor speed; and a fuel amount control unit to control a fuel amount F.sub.C supplied to the combustor, based on the estimated change rate M.sub.R. The control apparatus can preemptively control the fuel amount in response to variations in the compressed air amount by a momentarily changing turbine rotor speed and can limit the turbine inlet temperature to below the maximum allowable temperature, to protect the turbine and/or combustor against fluctuations in compressed air amount.

A gas turbine system can estimate an amount of compressed air supplied to a combustor and limit a fuel amount according to the estimated compressed air amount. A control apparatus of the system includes a sensing unit to measure the turbine rotor speed; a compressed air amount estimation unit to estimate a change rate M.sub.R of an amount of compressed air produced by the compressor and supplied to the combustor, based on the measured turbine rotor speed; and a fuel amount control unit to control a fuel amount F.sub.C supplied to the combustor, based on the estimated change rate M.sub.R. The control apparatus can preemptively control the fuel amount in response to variations in the compressed air amount by a momentarily changing turbine rotor speed and can limit the turbine inlet temperature to below the maximum allowable temperature, to protect the turbine and/or combustor against fluctuations in compressed air amount.

A method of operating a rotary machine below a minimum emissions compliance load in a response mode includes reducing a fuel split to zero. The fuel split apportions a total flow of fuel to the combustor between a first combustion zone and a second combustion zone. The method also includes determining a current operating temperature of the first combustion zone using a digital simulation of the rotary machine. The method further includes determining a target operating temperature of the first combustion zone. The target operating temperature enables the rotary machine to operate below a traditional Minimum Emissions Compliance Load (MECL) while still in compliance with emissions standards. The method also includes channeling a first flow of fuel to the first combustion zone. The first flow of fuel decreases the temperature of the first combustion zone to the target operating temperature.

A method of operating a rotary machine below a minimum emissions compliance load in a response mode includes reducing a fuel split to zero. The fuel split apportions a total flow of fuel to the combustor between a first combustion zone and a second combustion zone. The method also includes determining a current operating temperature of the first combustion zone using a digital simulation of the rotary machine. The method further includes determining a target operating temperature of the first combustion zone. The target operating temperature enables the rotary machine to operate below a traditional Minimum Emissions Compliance Load (MECL) while still in compliance with emissions standards. The method also includes channeling a first flow of fuel to the first combustion zone. The first flow of fuel decreases the temperature of the first combustion zone to the target operating temperature.

A gas turbine engine includes an inner annular combustor radially inboard of an outer annular combustor. An outer variable turbine vane array is downstream of the outer annular combustor and an inner variable turbine vane array downstream of the inner annular combustor.

A gas turbine engine includes an inner annular combustor radially inboard of an outer annular combustor. An outer variable turbine vane array is downstream of the outer annular combustor and an inner variable turbine vane array downstream of the inner annular combustor.

A gas turbine engine system includes an engine component comprising ceramic matrix composite materials, at least one control system configured to control at least a temperature of the engine component, and a controller. The controller includes a degradation map stored therein. The degradation map includes degradation fields, each field defined by a unique range of temperatures and stresses of the component and correlated to different types of degradation of the component. The controller is configured to determine a first temperature and stress of the component and a first field based on the first temperature and stress, determine a second field different from the first and a second temperature and stress that would locate the component in the second field, and instruct the control system to change the temperature of the component from the first to the second temperature to locate the component in the second field.

A gas turbine engine system includes an engine component comprising ceramic matrix composite materials, at least one control system configured to control at least a temperature of the engine component, and a controller. The controller includes a degradation map stored therein. The degradation map includes degradation fields, each field defined by a unique range of temperatures and stresses of the component and correlated to different types of degradation of the component. The controller is configured to determine a first temperature and stress of the component and a first field based on the first temperature and stress, determine a second field different from the first and a second temperature and stress that would locate the component in the second field, and instruct the control system to change the temperature of the component from the first to the second temperature to locate the component in the second field.