Hover Condition Variable CG

During hovering flight, a helicopter maintains a constant position over a selected point, usually a few feet above the ground. For a helicopter to hover, the lift and thrust produced by the rotor system act straight up and must equal the weight and drag, which act straight down.

If there is a wind in a specific direction, the rotor blades must be tilted to the opposite direction to counter the wind movement. Cyclic to be adjusted accordingly. The phenomenon is as simple as this.

But if the CG is shifted to say forward, the cyclic must be adjusted to tilt the aircraft back and vice versa.


The following project demonstrates the hover condition of helicopters with variable CG. The project is interactive and the user can change the position of CG as well as change the direction and speed of the wind. The following link will redirect you to the project page.

(For the mobile version, please go to the bottom of the page)

Hover Condition Variable CG on Scratch


Press the Left or Right arrow keys to change the wind speed. Minus means the opposite direction. 

Press the Up or Down arrow keys to change the position of the CG

This project demonstrates how the lift and weight react to changes in wind speed and different CG to maintain a hover condition.

In real life, the helicopters do not tilt so much. Also, the CG cannot be changed like this unless load is shifted. This is a mere exaggeration for example purposes only.




Mobile Version of Hover Condition with Variable CG on Scratch


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