Barnard Microsystems Limited

Developing Unmanned Aircraft Systems to benefit Mankind

Helicopter flight dynamics - Heli Flight Dynamics

These notes were taken from the Blade 4000 3D flight manual by Horizon Hobby Inc.

The collective control

The helicopter has a variable pitch main rotor. The "swash plate" is used to set the rotor angle-of-attack. The swash plate for the Blade 400 3D helicopter is shown next.

Helicopter flight dynamics

The collective control raises the entire swash plate assembly as a unit. This has the effect of changing the pitch of both blades simultaneously.

Helicopter flight dynamics

Moving the left hand stick, which usually controls the engine speed when flying a fixed wing model plane, this time sets the angle of attack of the main rotor, so increasing or decreasing the lift provided by the fixed speed rotor blades.

Helicopter flight dynamics

Helicopter flight dynamics

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The elevator pitch cyclic control

The cyclic control pushes one side of the swash plate assembly upward or downward. This has the effect of changing the pitch of the blades unevenly depending on where they are in the rotation. The result of the cyclic control is that the rotor's wings have a greater angle of attack (and therefore more lift) on one side of the helicopter and a lesser angle of attack (and less lift) on the opposite side. The unbalanced lift causes the helicopter to tip and move laterally.

Helicopter flight dynamics

Helicopter flight dynamics

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The aileron roll cyclic control

Helicopter flight dynamics

Helicopter flight dynamics

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The rudder yaw control

Rudder yaw is achieved by varying the pitch of the tail rotor.

Helicopter flight dynamics

Helicopter flight dynamics

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