Hi servceteam,
my heli is a TREX600 DFC with standard blades at main (600mm) and tail (95mm). Since a while - every time flying a right curve tail starts to wag / swing / shake. Just for 2 to 3 seconds until curve has been finished. Same behavoir all the time - flying slow or fast; at windy conditions and without any wind.
Spirit's log says "rudder limit has been reached". But can't be under this circumstances. Spirit's rudder limits has been configured correct!
Any idea ?
thanks in advance and br Siggi

Hi,

is this behavior occuring from the beginning?
If so, then the problem can be in the tail center position.

You can verify it by selecting Subtrim (tuning) option in the Servos tab. I recommend to set 3-4° there (slider closer to the boom).
Then dont forget to re-adjust rudder servo limits as well.

Other reason could be too high Rudder Delay or Piro Consistency. What values did you configured?

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Spirit System developer

Hi,
no I didn't change Spirit's core configuration - I just changed tail blades (from 92mm to 95mm) and tail rotor head - ofcourse after that I reconfigure rudder center position and rudder limits. Current value for "rudder delay is 15" and for "piro consistency is 160" - bute these values are unchanged since first setting (one year ago and more than 100 flights).

Yesterday I did some tests - what will happen if I change Gyro setting - result . If I set gyro to 68° comming from 63° it becomes worse. If i set Gyro to 55° coming from 63° it becomes a bit better (could be helpful to analyse ?).

There is no problem using rudder in every direction (fast, abrupt use, continously) if heli is at one position - (perfect stop behavoir and hold behavoir) - it only happens flying a right curve.

Today - looking at the values you asked for, I noticed that one sensor (the right once) is not zero (his value jumps inbetween 7 and 10) ; heli system does nothing (just standing at the table). Is that okay ?
Thanks in advance and br Siggi

Hi,

for your helicopter I recommend to set Rudder Delay to 8 and Pirouette Consistency to 165. This can improve performance in each case.
Always try to set the highest possible Gyro Gain (without any oscillation during fast forward flight or pitch pumps).

Longer blades are more efficient so rudder configuration must be changed.

What servo do you have on the rudder? Is it Align DS655?

_________________
Spirit System developer

Hi,
no it's DS620 - not the fastest but strong
Because I'm not a 3D runner - just fast flying normal fugures like laying 8 ; speeding straight forward ;
br Siggi

Hi ,
I think I got the reason of shaking tail.
I rebuild the main gear to helical version and rebuilding the tail system (front gear of tail drive) - I noticed that rudder rod's mount point in the middle of the tail boom goes a bit strong. I removed it .
that's all i did and it seems to be good - tested during 4 flights
Thanks and br Siggi