Aircraft APU-USA Aircraft Group Corporation

Date: 2025/4/27

The aircraft's APU (Auxiliary Power Unit) is an independent power unit that provides the power supply and pressure required during the aircraft's parking or engine shutdown. APU is usually located at the tail of the aircraft and has the characteristics of a gas turbine engine.

The working principle of APU is as follows:

1. Start-up: When the plane needs APU, the system will provide power to the activation circuit of the APU. Then, the control panel of APU will select to activate APU and select the appropriate working mode.

2. Fuel supply:

Once the APU is activated, the fuel pump will take the fuel from the main fuel of the aircraft.

Send it to the fuel controller in the system or fuel sedimentation tank. The fuel controller is responsible for adjusting the fuel flow and injecting fuel into the combustion chamber according to the condition.

3. Pressure gas supply: APU provides pressure gas through a turbine compressor. The gas generated by burning fuel makes the turbine compressor rotate, resulting in pressure.

4. Power generation: APU's generator rotor and turbine compressor are driven by the same shaft. When the compressor rotates, the generator also rotates to provide the required electricity for the aircraft.

5. Auxiliary functions: In addition to providing electricity and pressure, APU can also perform other auxiliary functions, such as providing Cabin Pressure caused by air pressure.

The APU of the aircraft is a very important component of the flight. It can bring many conveniences to aircraft, such as maintaining a comfortable environment and providing necessary electricity during aircraft downtime. At the same time, the working principle of APU also ensures its high efficiency and reliability, ensuring the safety and comfort of flight while providing the required power for the aircraft.