Since the emergence of aircraft in the world, although the structural form of aircraft has been continuously improved and the types of aircraft have been increasing, today, except for a few special types of aircraft, most aircraft are composed of the following five main parts, namely: wing, fuselage, tail wing, landing gear and power plant. They have their own unique functions.

(1) wing

The main function of the wing is to generate lift to support the aircraft to fly in the air; It also plays a certain role in stability and maneuverability. Wings are generally equipped with wings and flaps. Manipulating the wing can make the plane roll; Lowering the flap can increase the lift of the wing. In addition, the wing can also be equipped with an engine, landing gear and fuel tank. Wings come in different shapes and numbers. In history, it means that there have been biplanes, even many biplanes. But modern aircraft are generally monoplane.

(2) the fuselage

The main function of the fuselage is to carry passengers, crew, weapons, goods and various equipment; Other parts of the plane, such as the tail and the engine, can also be connected into a whole.

(3) Tail wing

The tail includes a horizontal tail and a vertical tail. The horizontal tail consists of a fixed horizontal fixed surface and a movable elevator. The vertical tail consists of a fixed vertical stabilizer and a movable rudder. The main function of the tail wing is to control the pitch and deflection of the aircraft and ensure that the aircraft can fly smoothly.

(4) Landing gear

Landing gear is used to support the aircraft to take off, land and park on the ground and horizontal plane. The landing gear of land aircraft is mostly composed of shock absorbing struts and wheels. It is used to support aircraft take-off, landing and taxiing, ground taxiing and parking.

(5) Power plants

The power plant is mainly used to generate tension or thrust to make the aircraft move forward. Secondly, it can also provide power supply for electrical equipment on the plane and gas source for air conditioning equipment and other gas-using equipment.

There are four kinds of modern aircraft power plants, which are widely used: one is aviation piston engine plus propeller propeller propeller; The second is a turbojet engine; The third type is turboprop engine; The fourth type is turbofan engine. With the development of aviation technology, rocket engines, ramjet engines and atomic aviation engines will be gradually adopted. In addition to the engine, the power plant also includes a series of systems to ensure the normal operation of the engine, such as fuel supply system.

In addition to the above five main components, the aircraft is also equipped with various instruments, communication equipment, pilot equipment, safety equipment and other equipment according to the needs of flight control and mission execution.

The first three points (the last three points) landing gear is an accessory device that supports the aircraft and moves the ground when it takes off and lands or taxies on the ground, and is called landing gear. The common form is a three-point wheel. If a pair of main landing gears are located behind the center of gravity of the aircraft and the other landing gear is located below the nose, it is the front three-point landing gear. If a pair of main landing gears are located in front of the center of gravity of the aircraft and the other landing gear is below the tail, it is the rear three-point landing gear. The former is adopted by modern aircraft, while the latter is adopted by old aircraft.

Turbojet engine, also known as air turbojet engine, is a kind of gas turbojet engine. It uses air as oxidant, and the gas ejected at high speed through the nozzle produces reactive thrust, which is called "turbojet" for short. The plane equipped with this engine is a jet plane. The engine must be composed of compressor, combustion chamber, turbine and tail nozzle. Thrust is expressed in cattle or kilograms.

Turboprop engine is derived from turbojet engine, which is a gas turbine aero-engine with propeller providing tension and jet reaction providing thrust. Its main component is a set of more propellers than turbojet engines, which are driven by turbines. This kind of engine is called "turboprop engine" for short. It is characterized by large thrust and low fuel consumption, and is mostly used in transport aircraft, maritime patrol aircraft and other aircraft. Power is expressed in equivalent horsepower.

Turbo-shaft engine is derived from turbojet engine, which is a gas turbine aero-engine that outputs shaft power through power turbine. Its working feature is to convert almost all available energy into shaft power output, and use high-speed rotating shaft to drive helicopter rotor and tail rotor through reducer. Its power is expressed in axle horsepower. It is the main power plant of contemporary helicopters.

Turbofan engine is a gas turbine aero-engine developed on the basis of turbojet engine, and its reverse thrust is produced by exhaust of nozzle and exhaust of fan. Its main component is one more fan than turbojet engine. The engine is called "turbofan" or "internal and external culvert engine" for short. Part of the thrust is generated by the high-speed gas ejected from the nozzle, and the other part is generated by the air reaction force driven by the fan. It is characterized by large thrust and low fuel consumption. It is often used in modern passenger planes, transport planes, fighters and bombers.