Flapping to Equality

During the movement of a helicopter rotating blade, the speed of airflow over the advancing blade is more than the retreating blade, resulting in the production of an unequal amount of lift. This is called a       dissymmetry of lift. To correct this aerodynamic imbalance, the blades are allowed to perform a series of controlled movements to produce equal amounts of lift. This process of equalization is called flapping to equality.

        


Nil wind hover, no flapping, AOA is constant, the lift is equal on all sides






Advancing Blade, Flapping up, AOA is reduced, the lift is reduced




Retreating Blade, Flapping down, AOA is increased, the lift is increased








The following project demonstrates the flapping to equality of helicopters. The project is interactive and the user can increase or decrease the velocity of the helicopter. The following link will redirect you to the project page.
(For the mobile version, please go to the bottom of the page)

Flapping to Equality on Scratch

Simple helicopter simulation to explain the phenomenon of Flapping to Equality.

Press the up or down arrow to increase or decrease the velocity of the helicopter.

The Helicopter on the top right has dissymmetry of lift due to lack of flapping and has a rolling moment.

However, the helicopter on the bottom right has the symmetry of lift due to flapping and has no rolling moment.





Mobile Version of Flapping to Equality on Scratch





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