Servo drift when model is stationary

  • Hello Richard

    I am experiencing the servos slowly drifting when the model is perfectly still and gyro active. As soon as I move the control stick the servo for that control will centre but after a few seconds the servo starts to drift if I leave the stick alone. It happens in both normal and heading mode but not off course when the gyro is off . It seems worse the higher the gain setting.

    I have flown the model (the gains are quite high at between 60-80%). It happens only with the elevator and rudder servos which are S bus servos (futaba) connected using powerbox S-Bus connectors and leads to Sbus output on the Royal (It makes no difference which output). I have no trouble with the same Sbus aileron servos that are on the other Sbus output.

    The Royal manual does mention this could happen but says zeroing the gyro should solve it which it does not. I have the igyro srs and Mercury SRS in other models and on these the control surfaces are perfectly still at normal gain settings when model is stationary and gyro active.

    Everything else for the Royal gyro is as per the software default.

    Any ideas?



  • PS the unit was sent to Powerbox about six months ago to be checked/serviced (not for this problem but just to check all OK before I installed in new model) and came back reporting no faults found. The serial number 109248 (also stickers on back with 4494 and blue circle) Thank you

  • Hello,

    18.9 is the latest release and then also the latest hardware.

    Just to understand: The Gyro needs some seconds after turning on where the model stands still. It doesn´t matter when you give him the time, but anytime between turning on and start.

  • Yes I understand that. The model is perfectly still on the table after switching on the powerbox and gyro. The servo starts to drift slowly straight away in mode 2 or 3 . If I zero the gyro, again keeping plane still, it makes no difference and the servos drifts.

  • I received my Powerbox back today with new sensor all working perfectly now with no drift. Thanks for a fantastic backup service, all in less than a week back to UK and very low cost!

    Please can you confirm that the factory default boost setting should be 0 for both normal and heading flight modes.

    Is it correct that even after turning flight gain to 100% in fight assistant does not cause a model to oscillate, I need to consider a higher boost setting and test fly again?

    Can you confirm that if I set crow (airbrake) on aileron will this mean a) that heading mode is no longer active as the aileron is no longer in centre position and b) normal mode will also be less effective?

    Thank you

  • Hello,

    boost is 1 - standard.

    If you don´t get oscillations with 100% don´t change the boost. Use the Gainx4 function to get more gain. But you have to testfly new.

    I recommend to do a new testflight assistant to adjust the new sensor, before you try Gain x 4

    Crow: yes- exactly like you have written

  • Hello

    As you can see from this thread, more than a year old, my Royal was causing servos to drift randomly when model was perfectly still in flight mode 2 or 3.

    I returned the unit and it came back with problem solved with new gyro sensor.

    Unfortuantely, the unit is doing it again but this time, much worse and if there is any slight movement or vibration of the Royal unit in the model, the control surface might even jump suddenly. Of course all goes back to nomal if gyro is put back to mode 1.

    Given this unit is more than 3 years old (black plastic unit but silver plastic screen) and mpore than 12 months since you replaced the last gyro sensor, is it worthwhile to send it back? I am now flying but not using the gyro as I cannot trust it.

    Second question is I have bought a brand new Royal (so you can see I am still a fan despite these issues :-). Is there any way I can transfer or copy over all my existing non-gyro settings from one unit to another and save a lot of time setting up again?

    with thanks


  • Hello,

    if we should solve the problem you should send it back. If you want to have it replaced completely we can decide to do that once it´s here and we can make you an offer for that. If it has an silver screen it´s at least 8 years old.

    Yes- you can copy the model data with the USB interface and the PowerBox Terminal

  • I ve copied over model data into new Royal unit and installed it in my model. It is rock steady, no drift or glitches. I ll return the old unit to Donauworth and wait for your evaluation please as I think it has had its day.

    To be on safe side, I will use testflight assistant to set the gyro sensor in the new Royal unit.

    Thanks again for your help.