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Can a helicopter apply full cyclic and then full collective at the same time? Would'nt the blades on one side (opposite of the intended tilt direction) have already maxed their aoa, resulting in a net dissapearence of dissymmetry of lift, with the effect equal to just applying full collective? Or does full collective + cyclic result in even greater aoa (the inputs add up)?

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    $\begingroup$ Full cyclic in which direction? the side of retracting blade? $\endgroup$ – mins Feb 17 at 14:25
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Multiple questions here. Assuming by full cyclic you mean pushing the cyclic to a mechanical stop while pulling full collective to the mechanical stop, the answer is yes, at least for the Bell 206, a very common turbine helicopter in use worldwide. There are no restrictions with regards to full flight control inputs. At stabilized hover on a no wind day there is no appreciable dissymmetry of lift as aerodynamically, there is no advancing or retreating blade. If you push the cyclic straight and full forward, mechanically tilting the rotor disc, the instant you move forward you now have dissymmetry of lift between the advancing and retreating blades

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Yes it is possible to apply both max collective and max cyclic.

The three actuators that move the swashplate obviously have limited range of motion - what happens if some of the range is consumed by cyclic stick deflection, and collective action will consume more than the remaining actuator range. Is how I now understand your question.

In larger helicopters, the control mixer is designed with the following priority:

  • Collective: the power handle.
  • Pedals: the anti-spin device, also for when you need to apply more power.
  • Cyclic: for reaching your destination.

Collective and pedals have major safety related functions.

How the priority is implemented depends on the size of the helicopter, larger ones have irreversible boost actuators between control and swashplate, and are designed such that at the cyclic travel stops move as a function of collective/pedals. The stick travel limits - with the stick inside the limits there is no effect with boost on, with the cyclic fully extended it will come back a bit at full collective.

Smaller heli's without irreversible boost will act like a lever, with collective or pedal at one end and the cyclic at the other. The lever arm will favour the collective/pedal end.

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