Hello,

I´am flying a TRex 550X with a Spirit Pro.

Made 4 flights with it that morning.
On the third start my heli began immediately with spool up to turn right on the ground and did not stop by itself. (perhaps I did not set the Tail rotor to neutral position before spooling up?).
I thought in my unexperience, I could start with turning going on and stop turning, when I´m in the air. Therefore I did not do anything to stop turning on the ground and took off with the heli turning further on. I was sure to stop the turnings without problems, when the heli is in the air and the spirit would compensate the rightturn.

But no compensation happened and the heli continued to turn tot he right; I had to steer with full left rudder against the turning and had big difficulties to bring the heli back to the ground without damage.

Before the next flight I setted the tailrotor in neutral position before spool up. The heli worked without any problem.

I hope now, not setting the tailrotor before spoolup in neutral position and taking off without stoppng turning on the ground were the reasons for the unstoppable turning in flight.
Indeed there is a rest of fear, that the reason for that incident could be a damage of the spirit, which could happen always again. I wonder, why the FBL did not compensate the turnings, after landing the tail rotor position got always back in position for turning right.

Could You give me any advise, to handle with this?

Thank You in advance and with best regards


Roland

PS: The Spirit, I flew had no crash and I´m using Heading Hold Mode.

Hello,

you are right that the tail slider should be approximately in the middle while lifting off.


It look like your gyro gain is very low. For this reason also steering was a problem and it required a bigger angle to stop the rotation.

Did you configured recommended 50% for the first flight?

_________________
Spirit System developer

Hello Tomas´,

thank You very much for quick reply.

My Gyro Gain is in all three banks 60%.

I think the main reason for that strange behavior was my own mistake, when I lifted off with a turning helicopter.
The only thing, I do not not understand is the fact, that the heli did not stop the turning in the air.
Even after landing was the tail rotor in full "turn right" position and even got always back in that "turn right" position when I steered in "turn left" position.
It seemed almost, that the pitch slider is locked in the "turn right " position.

Thats the only point, why I ´m a little bit afraid, that this incident is perhaps connected with a damage in my spirit. I can hardly imagine this, because this FBL did work very well since March this year and the rescue function is the best I have ever seen. ThereforeI would be very glad, when the mistake was only on my side and you could confirm this to me.


With best regards

Roland

PS: I attached provident my configuration files

Hello,

if you are getting unstoppable rotation after lift off, then it is always caused by a wrong reversing of the Tail servo.
In that case it will always start to spin very rapidly and you will have a hard time to stop it.

Are you perfectly sure that your tail servo is reacting/compensating correctly? If not, then it will happen always.

The tail must hold immediately after lift off even if you are not doing anything.

_________________
Spirit System developer

Hello Tomas,

thanks for Your reply.

Compensation of tail servo is correct, I´ve made with this configuration perhaps 50 flights since beginning of May.
But I hope still, that my own mistake was responsable for that behavior of the heli. Strange was for me only the fact, that the tail pitch slider got after landing always back in the "rudder right" Position like locked. When I made on the ground a steering to the left, the pitch slider reacted well, but after release of the rudder stick got immediatly back in "rudder right" Position.
Therefore I am a Little bit afraid, this incident could be based on a Hardware Problem.
Although the next flight was well, I´m a Little bit afraid, that this behavior can occur another time.

But I hope still, that You can confirm to me, that it was my own mistake.

With best regards

Roland

There is possibility that there is failing potentiometer in your radio. This could give you for example full speed turns unexpectedly.
But this will happen on any model with higher occurance over time. It could be visible sometimes directly in your radio in channel monitor.

Or if the model has extremely high vibrations it could cause similar troubles in some RPMs too. This can be verified by vibration measurement.

There should be no other reason for such behavior.

_________________
Spirit System developer

Hello Tomas´

the solution of a failing potentiometer is imaginable for me, because the vibrations are very low (according to telemetry data an average data of 4 when hovering). Also I got never a message in the log, that vibrations are high.

Is it too much to ask, what You would in such a case? I´m at a loss now

Nevertheless, thank You very much for Your time spending with my Problems.

With best regards

Roland

Hello rolandk,

I would try to get a similar radio from someone else for testing or I would use another (expendable?) modell to test your radio with. Such a modell could be a small plane with two channels (for ex. UMX Radian from Hobby Horizon) since your problem is the gear/rudder function.

He meant failing potentiometer on your radio, not on the heli (vibrations not relevant). As in your rudder stick is giving false inputs, check your radio monitor screen to see if it's at zero when you're not touching the sticks. You may have also accidentally bumped one of the trims making rudder have a continuous input. You should be able to see this in your transmitter's monitor screen and/or the spirit diagnostic screen. If it is getting false inputs you can increase the deadband under advanced until it no longer sees it, but it would be best to have it repaired/replaced if that's what it is.

Also 50-60% tail gain for the 550x is VERY low, I see you have a 1x multiplier (no multiplier). I run mine at 70% gain in the tx, plus 1.3x multiplier so really about 90%.