The chapter explains the composition of aircraft power plants of various types and shows the properties of aircraft engines (with the focus on jet engines). The chapter also covers the features of air intakes, both subsonic and supersonic, the arrangement of the intake on an aircraft, as well as the design of exhaust systems and thrust reversers. The chapter explains the installation of engines on aircraft, the noise of jet engines, and its reduction. Finally, the chapter presents the composition and arrangement of fuel systems on aircraft.