A powerplant for an aircraft comprising: at least two gas turbine engines (20, 20'), and at least one closed-cycle arrangement for recuperating heat from the at least two gas turbine engines (20, 20') 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 (20, 20') 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 (20, 20'), and at least one closed-cycle arrangement for recuperating heat from the at least two gas turbine engines (20, 20') 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 (20, 20') 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 (20, 20') 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;