How to adjust helicopter parameters, helicopter model version 1

0 General information

Please read this file for a description of helicopter parameters.

1 Suggested steps

It is assumed that values for mass and inertia already are correct.
  1. Copy and modify the values of an existing model.
  2. Set all of the following values to zero: aero.yaw.dist, aero.pitch.dist, aero.roll.dist, aero.yaw.moment_mul, aero.yaw.off, aero.yaw.cp_to_yaw, aero.roll.ForwardToRoll, aero.yaw.vane, aero.pitch.vane
  3. Start CRRCSim, set wind speed and thermals to zero. Load the model you want to adjust. Save settings. Easiest way to try settings is to just quit CRRCSim (hit 'q'), edit and save parameter file, start CRRCSim again.
  4. If power.fixed_pitch is set, adjust aero.pitch.off and power.automagic.F to set maximum climb rate and climb rate at neutral stick.
    For a collective pitch heli, adjust aero.pitch.off, aero.pitch.ctrl and power.automagic.F.
  5. Adjust aero.yaw.ctrl, aero.pitch.ctrl, and aero.roll.ctrl for full stick rotation rates in rad/second.
  6. Does the heli rotate around the correct point? Adjust its center of gravity.
  7. Adjust lift in ground effect with GroundEffect.climb.mul and GroundEffect.climb.exp.
  8. Fly around and adjust aero.yaw.vane, aero.pitch.vane, and aero.speed.damp.
  9. Remove aero.pitch.damp and aero.pitch.dist. They are taken from aero.roll.damp and aero.roll.dist if they don't exist.
  10. Adjust aero.roll.damp and aero.roll.dist. You may want to tweak Disturbance.tau_filter and Disturbance.time, too.
  11. Do you think aero.pitch.damp and aero.pitch.dist should differ from aero.roll.damp and aero.roll.dist? If this is the case: define them.
  12. Adjust aero.yaw.damp, aero.yaw.damp_min_rel, and aero.yaw.dist.
  13. If the model has a heading lock gyro, set aero.yaw.HeadingHold to something greater than zero and aero.yaw.moment_mul to one.
    Otherwise, you should ideally increase aero.yaw.moment_mul to one and adjust aero.yaw.off and aero.yaw.cp_to_yaw. Setting aero.yaw.moment_mul to something smaller than one makes this easier -- but maybe less realistic.
  14. Adjust increase of disturbances in ground effect: GroundEffect.dist.mul and GroundEffect.dist.exp.
  15. Finally, you may want to tweak aero.roll.ForwardToRoll.