JWatson
Veteran
Location: College Station, Texas
My Posts This: Topic Forum | I believe that is a text quoted fron www.heli-rnd.com under Sk360 Flight tuning. Here : http://www.heli-rnd.com/Skookum/SK_..._reference.html
Basic tuning steps
1. Slowly take off (not to give any cyclic input before actual taking off)
2. In a stable hover, test the cyclic control by giving very small input to all directions
3. if the heli slight drift in hover, you need a higher Hiller gain but please do increase "progressively" until a solid hover. The heli may oscillate as you would have on a tail gyro, the gain is then too high. You can adjust individual cyclic control Hiller gain if only one axis osciallates
4. In a stable hover, give the heli a rapid elevator input and center again sharply
* if the heli starts slowly, turn up the Bell gain
* if the heli bounces a few times before coming to a hover, turn down the Bell Gain
5. In a stable hover, sharply increase the collective pitch and observe if the heli tilts to any direction, if the heli tilts:
* nose up - tune down the elevator tail drag compensation under Advance tab and vice versa
* right - tune down the aileron tail drag compensation and vice versa
6. Test a fast forward flight, if the heli bounces like a dauphine, nose up and down, turn down the elevator dampening gain under "control" tab
Now you are basically set, in case you need faster cyclic roll, increase the control rate under "control" tab, the heli can roll as fast as 360 degree/second provide that sufficient cyclic pitch is available; hence, about ten degree cyclic pitch is recommended. However, you need to increase relative bell gain proportionally;
For example: Control rate increased from 210% to 260%, Bell gain is 30%, then Bell gain should be increased to :
30% X 260 / 210 = approximately 37%
Other settings are
Hiler Decay - increasing Hiller Decay will increase the stability of high rate piro and better tic toc. This will give a feel of flying heavier main blades
Use Base Gain Directly - select this option will simply disable both pots on the gyro, all gains are set via the software
Use Gain Channel Input - The left over port on the gyro is reserved for two band set up, you can connect it to any available channel and select "Use Gain Channel Input" under control tab. In this mode, you can swtich between two pre-set profiles with one at each side of the channel signal. Both the pots on the gyro will become Bell gain for each profile and the Hiller gain is now adjustable by changing the ATVs
There is an FAQ about the relationship between Gains and Actual Gain. This is only a matter of presentation to show the relationship between the elevator gain and aileron gain.
For example: if you have an actual Bell Gain of 30%, the elevator and aileron gains are 30% and 40%...
Increasing 5% of Bell Gain by turning the pot will increase the elevator gain from 30% to 35% when the aileron gain increases to (40% / 30 X 35) = approximately 46%, same applies to other gains
More set up tips are available in the download page.
Hope that helps,
Jarrett
Jarrett Watson
PowerHelis.com |
