Balancing lift across the rotor disc is important to a helicopter's stability.

In a retreating-blade stall, however, only the retreating half of the helicopter's rotor disc experiences a stall.

In typical flight, the rotor disc directs the airflow downwards, creating Lift (force).

Buoyant aircraft travel so slowly they do not need them, and helicopters achieve lateral flight control by manipulating their rotor discs.

A main rotor blade was either observed to separate or was seen separated in the vicinity of the main rotor disc.

Coaxial - One rotor disc above the other, with concentric drive shafts.

In forward flight the advancing blade has a higher airspeed than the retreating blade, creating unequal lift across the rotor disc.

In sunlight the rotor disc becomes visible and this gives more information on the roll attitude of the model.

In this case, dissymmetry of lift and blade flapping could cause the rotor disc to tilt aft.

The actual output at the turbine shaft is equal to the stage work minus the losses due to rotor disc and bearing friction.