A powerplant for an aircraft comprising: at least two gas turbine engines , and at least one closed-cycle arrangement for recuperating heat from the at least two gas turbine engines and supplying power to at least one power-demanding system, wherein the closed-cycle arrangement comprises: - a closed circuit channeling a working fluid subjected to a thermodynamic cycle; - at least one pre-cooler (2.1, 2.2) configured to transfer heat from the working fluid to a heat sink; - the heat sink in thermal communication with the pre-cooler (2.1, 2.2), the heat sink being a fuel tank and/or an airframe surface; - at least one pumping element configured to move the working fluid through the closed circuit ; - at least two primary heat exchangers (4, 4', 4"), each one configured to transfer heat from a respective gas turbine engine to the working fluid; - at least one expanding element configured to drive a gearbox and an output shaft by the expansion of the working fluid; wherein the output shaft driven by the expanding element is connected to at least one electrical generator configured to generate electrical power; - a power conversion system configured to receive the generated electrical power by the electrical generator and to accommodate and supply it to the at least one power-demanding system; wherein the closed-cycle arrangement is adapted to be partially housed within the airframe structure of the aircraft, so that at least the pumping element , the expanding element , the electrical generator , and the power conversion system are housed in said airframe structure . at least two gas turbine engines , and at least one closed-cycle arrangement for recuperating heat from the at least two gas turbine engines and supplying power to at least one power-demanding system, wherein the closed-cycle arrangement comprises: - a closed circuit channeling a working fluid subjected to a thermodynamic cycle; - at least one pre-cooler (2.1, 2.2) configured to transfer heat from the working fluid to a heat sink; - the heat sink in thermal communication with the pre-cooler (2.1, 2.2), the heat sink being a fuel tank and/or an airframe surface; - at least one pumping element configured to move the working fluid through the closed circuit ; - at least two primary heat exchangers (4, 4', 4"), each one configured to transfer heat from a respective gas turbine engine to the working fluid; - at least one expanding element configured to drive a gearbox and an output shaft by the expansion of the working fluid; wherein the output shaft driven by the expanding element is connected to at least one electrical generator configured to generate electrical power; - a power conversion system configured to receive the generated electrical power by the electrical generator and to accommodate and supply it to the at least one power-demanding system; - a closed circuit channeling a working fluid subjected to a thermodynamic cycle; - at least one pre-cooler (2.1, 2.2) configured to transfer heat from the working fluid to a heat sink; - the heat sink in thermal communication with the pre-cooler (2.1, 2.2), the heat sink being a fuel tank and/or an airframe surface; - at least one pumping element configured to move the working fluid through the closed circuit ; - at least two primary heat exchangers (4, 4', 4"), each one configured to transfer heat from a respective gas turbine engine to the working fluid; - at least one expanding element configured to drive a gearbox and an output shaft by the expansion of the working fluid; wherein the output shaft driven by the expanding element is connected to at least one electrical generator configured to generate electrical power; - a power conversion system configured to receive the generated electrical power by the electrical generator and to accommodate and supply it to the at least one power-demanding system; <EOS>