Flap is a structure fixed on the wing of an airplane. They are also called baffles.

They play an important role in safety, improving aircraft performance, improving aircraft stability and reducing aircraft noise.

First of all, they help to improve the safety of aircraft. Installing flaps can resist the instability of airflow, help suppress the impact of airflow on aircraft wings, and help reduce the possibility of stall.

Secondly, they can improve the performance of aircraft. Flaps can change the shape of aircraft wings, thus improving aerodynamic characteristics, improving maneuverability, increasing the drag of wings, reducing the drag reduction rate of wings, and thus increasing the lift of wings.

Third, they can improve the stability of aircraft. Because the flap can change the shape of the wing, the wing can better resist the turbulence of the air, thus improving the stability of the aircraft.

Fourth, they can reduce aircraft noise. Because flaps can reduce the turbulence of aircraft wings, thus reducing the noise generated during flight, thus making the aircraft quieter in the air.