A method for controlling at least a first turboshaft engine and a second turboshaft engine of a rotorcraft, which set a common kinematic linkage in motion, the rotorcraft having an output electric machine cooperating with a first output kinematic linkage of the first turboshaft engine, the rotorcraft having an input electric machine cooperating with a gas generator of the second turboshaft engine. The method includes the following steps: supplying fuel to the first turboshaft engine, operating the output electric machine in electrical energy generator mode, supplying fuel to the second turboshaft engine, and operating the input electric machine in motor mode in order to supply a second non-zero power to said common kinematic linkage.

Methods and systems for operating an aircraft having two or more engines are described. The method comprises operating the two or more engines of the aircraft in an asymmetric operating regime, wherein a first of the engines is in an active mode to provide motive power to the aircraft and a second of the engines is in a standby mode to provide substantially no motive power to the aircraft, receiving a request to exit the asymmetric operating regime, the request having at least one parameter associated therewith, selecting one of a plurality of available exit protocols as a function of the at least one parameter, and applying the exit protocol by commanding the engines accordingly.

Methods and systems for operating an aircraft having two or more engines are described. The method comprises operating the two or more engines of the aircraft in an asymmetric operating regime, wherein a first of the engines is in an active mode to provide motive power to the aircraft and a second of the engines is in a standby mode to provide substantially no motive power to the aircraft, receiving a request to exit the asymmetric operating regime, the request having at least one parameter associated therewith, selecting one of a plurality of available exit protocols as a function of the at least one parameter, and applying the exit protocol by commanding the engines accordingly.

A turbo cluster gas turbine system includes: at least one combustor configured to combust a fuel to generate a combustion gas; an output turbine configured to be driven with the combustion gas from the at least one combustor; and a plurality of supercharging systems configured to supply compressed air to be supplied to the at least one combustor, wherein each of the supercharging systems includes: a first turbocharger having a rotation shaft formed separately from a rotation shaft of the output turbine and configured to be driven with the combustion gas from the combustor; a first air line for supplying compressed air compressed by a compressor of the first turbocharger to the combustor; and a first combustion gas line for supplying the combustion gas from the combustor to a turbine of the first turbocharger.

A turbo cluster gas turbine system includes: at least one combustor configured to combust a fuel to generate a combustion gas; an output turbine configured to be driven with the combustion gas from the at least one combustor; and a plurality of supercharging systems configured to supply compressed air to be supplied to the at least one combustor, wherein each of the supercharging systems includes: a first turbocharger having a rotation shaft formed separately from a rotation shaft of the output turbine and configured to be driven with the combustion gas from the combustor; a first air line for supplying compressed air compressed by a compressor of the first turbocharger to the combustor; and a first combustion gas line for supplying the combustion gas from the combustor to a turbine of the first turbocharger.

An aircraft propulsion system includes a fan section that includes a fan shaft that is rotatable about a fan axis. The fan shaft includes a fan gear. The aircraft propulsion system also includes a boost turbine engine that includes a first output shaft that includes a first gear that is coupled to the fan gear. The boost turbine engine has a first maximum power capacity. The aircraft propulsion system further includes a cruise gas turbine engine that includes a second output shaft that includes a second gear that is coupled to the fan gear. The cruise turbine engine has a second maximum power capacity that is less than the first maximum power capacity of the boost turbine engine. The fan section produces a thrust that corresponds to power input through the fan gear from the boost turbine engine and the cruise turbine engine.

A gas turbine power plant comprises a gas turbine, a power turbine, a clutch, an electrical generator and a controller. The power turbine is fluidly connected to the gas turbine without any mechanical connection. The clutch comprises an input mechanically connected to the power turbine and an output mechanically connected to the electric generator. The controller can identify that a speed of the electric generator is greater than a speed of the power turbine, determine a difference between the speed of the electric generator and the power turbine, in response to the difference being greater than a threshold, control the gas turbine to a first maximum acceleration of the power turbine, and in response to the difference being equal or less than to the threshold, control the gas turbine to a second maximum acceleration of the power turbine that is less than the first maximum acceleration.

A method for detecting wear before failure of a free-wheel, the free-wheel comprising a driving part integrated into an upstream mechanical power transmission system and a driven part integrated into a downstream mechanical power transmission system. The method comprises determining an oscillation measurement of a monitoring parameter within the upstream or downstream mechanical power transmission system, determining a value of at least one dynamic parameter characteristic of the oscillation measurement or of a transform of the oscillation measurement in a frequency reference frame, and generating an alarm when the value of the dynamic parameter reaches at least one wear threshold.

In a cryogenic combined cycle power plant electric power drives a cryogenic refrigerator to store energy by cooling air to a liquid state for storage within tanks, followed by subsequent release of the stored energy by first pressurizing the liquid air, then regasifying the liquid air and raising the temperature of the regasified air at least in part with heat exhausted from a combustion turbine, and then expanding the heated regasified air through a hot gas expander to generate power. The expanded regasified air exhausted from the expander may be used to cool and make denser the inlet air to the combustion turbine. The combustion turbine exhaust gases may be used to drive an organic Rankine bottoming cycle. An alternative source of heat such as thermal storage, for example, may be used in place of or in addition to the combustion turbine.

Systems and methods for operating an engine in a multi-engine rotorcraft are described herein. A first parameter indicative of torque of a first engine is obtained. A decrease of the first parameter is detected. In response to detecting the decrease of the first parameter, an autorotation of the rotorcraft is accommodated, A second parameter indicative of torque of a second engine of the rotorcraft is assessed while accommodating the autorotation. If the second parameter has not decreased, a shaft shear of the first engine is identified and accommodating of the autorotation is ended. If the second parameter has decreased, the accommodating is maintained.