an engine mounted in a fuselage of the air vehicle;

a generator engaged to the engine and configured to be driven using power from the engine;

a compressor engaged to the engine and the generator and configured to be driven by the engine or the generator;

a battery electrically connected to the generator and configured to store electricity generated by the generator;

an electricity distributor connected to the generator, the battery and a main propulsion apparatus and configured to distribute electricity generated by the generator to the battery and the main propulsion apparatus;

at least a nozzle apparatus connected to the compressor and configured to jet pressurized gas supplied from the compressor, to an outside of the fuselage;

a first clutch mounted between the engine and the generator and configured to selectively engage transmission of power from the engine to the generator; and

a second clutch connected to the first clutch in series to selectively engage transmission of the power from the engine to the compressor via the first clutch,

wherein an output shaft of the engine, the first clutch, the second clutch and an input shaft of the compressor are coaxially disposed in series,

wherein the at least one nozzle apparatus includes a lift-generating nozzle apparatus configured to jet the pressurized gas in a downward direction of the fuselage of the air vehicle and a thrust-generating nozzle apparatus configured to jet the pressurized gas in a rearward direction of the fuselage of the air vehicle,

wherein the lift-generating nozzle apparatus includes a front nozzle disposed at a front side of the fuselage and a rear nozzle disposed at a rear side of the fuselage,

wherein the front nozzle is connected to the compressor via a front gas pipe, the front gas pipe includes a front gas valve and the front gas valve controls a flow rate of the pressurized gas jetted through the front nozzle, and

wherein the thrust-generating nozzle apparatus includes: