10 Wonderful mysteries about airplanes that you probably did not know about

Auxiliary motor unit

When we get on the plane, and yet the aircraft engines are not turned on, we’ll hear a sound similar to that of the engine. This sound is auxiliary engine that, in the absence of the main engines, provides the necessary power for the control units of the aircraft. This unit also turns on motors. This auxiliary unit will also be very helpful in airports that do not have the proper equipment and the possibility of repairs and maintenance of the engines.