Aircraft engine, a unit of the power plant (PP) of an aircraft, which serves to create potential energy and transform it into kinetic energy of the aircraft (airplane, helicopter, cruise missile, airship, etc.). Depending on the principle of operation aviation engines are divided into reciprocating internal combustion engines, jet engines, rocket engines, steam engines, nuclear, electric engines. The main requirements to aircraft engines: high reliability, operating life and fuel efficiency (requirements to specific fuel consumption), thrust-to-weight ratio, small mass, size and shape with the necessary thrust or power. The AC structure depends on the engine type and aircraft type (propeller or jet, subsonic or supersonic) and includes inlet (air intake and its control means, protection against icing and dust) and outlet devices (jet nozzle, noise muffler, noise suppressor), air duct, gas generator (compressor, combustion chamber, turbine), afterburner, propulsor (propeller), fuel system (fuel tanks, pumps, refueling subsystem, in-flight refueling, emergency in-flight fuel drainage, etc. etc.), oil system, firefighting system, attachment assemblies and placement nacelle (streamlined shell), etc.
The degree of integration or disintegration with units and control systems depends on the structural design. In aircraft engines assembled according to the modular scheme, the gas generator is isolated (engine PD-14, developer JSC Aviadvigatel Perm, engine Pratt & Whitney PW1000G development company Pratt & Whitney, USA). Most aircraft engines have a gas generator combined with a nozzle, reversing apparatus, afterburner, etc. In hypersonic aircraft engine air intake is the entire lower fuselage hull (Tu-2000).
Types of engines that are in operation in aviation: internal combustion engine (ICE); airjet engine (ATE): turbojet engine (TRD), ramjet engine (ramjet), turboprop engine (TVD), turbofan engine (TVV); rocket engine.
Aircraft engine concepts of the past include the steam jet engine.
Promising concepts: atomic (nuclear) aircraft engine; aircraft electric engine; solar sail; space elevator.