Weird rudder behaviour

[9GTurn 6]

I have a problem with the rudder automatically moving out of centre when on the ground and the airspeed builds.

So normal taxi travel is fine, but when I throttle up and start take off roll the rudder trim moves which makes the take off tricky!!  The same happens when I land, once wheels touch down the rudder goes off centre, sometimes to the max, but once I trim it to the centre it doesn't happen again.  Even if I throttle up on a practice landing, touch and go and lift off the rudder stays centred.

I've had to set up a key combination to centre the rudder.  But I wondered why its doing it.  Running P3D v4.5 HF2 

[argosafe 14]

Rudder controls have always been a weak point for me.  I've tried tuning them etc, but always get the sense of either lag or large deflection rather than smooth control.  Maybe there is a method out there? 

[Dominique_K 10,133]

On 2/5/2020 at 6:19 PM, 9GTurn said:

I have a problem with the rudder automatically moving out of centre when on the ground and the airspeed builds.

So normal taxi travel is fine, but when I throttle up and start take off roll the rudder trim moves which makes the take off tricky!!  The same happens when I land, once wheels touch down the rudder goes off centre, sometimes to the max, but once I trim it to the centre it doesn't happen again.  Even if I throttle up on a practice landing, touch and go and lift off the rudder stays centred.

I've had to set up a key combination to centre the rudder.  But I wondered why its doing it.  Running P3D v4.5 HF2 

As you do not specify the aircraft you fly when it happens, a general procedure would be to verify that you don’t have a double assignment. 

[Wells 5]

Also check that the yaw damper isn't turned on 

[9GTurn 6]

Thanks for the replies.

No specific aircraft it happens with everything i fly including the default jets.

No yaw damper on the ground and it only occurs when the speed goes over a certain number. Will check for double assignments, but what assignment causes a rudder input as speed builds?

[Dominique_K 10,133]

18 minutes ago, 9GTurn said:

Thanks for the replies.

No specific aircraft it happens with everything i fly including the default jets.

No yaw damper on the ground and it only occurs when the speed goes over a certain number. Will check for double assignments, but what assignment causes a rudder input as speed builds?

Just advising you a first step approach in debugging your problem, not a miracle solution 😉.

A weird behavior of this kind with well calibrated and good quality (no wornout pots !) controllers (joystick, throttle, rudder with brake pedals) smacks of a double assignment.

But It could be something else of course. By the way, I suppose that you checked off auto-rudder. If not, it may kick in if there is some noticeable crosswind. 

 

[9GTurn 6]

Ok.  I took the Carenado SR22 for a little fly about and once the wheels where rolling over 50kts on the take off the rudder went out of whack.  I've set up a key combo to reset the rudder trim to centre.  However the SR22 doesn't appear to have rudder trim so it never reset.

I saved the scenario and reloaded when in the air and the rudder trim was reset to centre with no interaction from me.

When I landed at LOWI just as there was wheel rotation the rudder went out of whack again and threw me off the side of the runway as a full opposite rudder does nothing to centre it.

I use FSUIPC to control my assignments with the controllers checked as disabled in the P3D controls and assignments which it confirms they are off.  I have checked and reassigned my axis in FSUIPC so where am I looking to check for double assignments?  Auto rudder is definitely off.

I am using 6 month old Thrustmaster TPR pedals so no bad hardware providing bad inputs.

Would a reinstall of the Client module fix this?

This is really screwing up my flying 😔😕

[spokes2112 179]

This really sounds like it is FSUIPC calibration problem and you have both rudder and steering tiller assigned to the rudder axis.
Either the rudder or the steering tiller is out of calibration.
Basically, when it comes to the internals of the sim, the rudder and steering tiller are the exact same thing, just applied differently to the situation (ground friction vs aerodynamics) . All it does is to provide 2 separate calibrations ( on ground taxiing or rudder now effective ) for the human controlling the airplane. IE -
Changing the rudder will change the steering tiller using the calibration provided for the rudder.  (> 50knots, adjustable in FSUIPC.ini) 
Changing the steering tiller will change the rudder using the calibration provided for the tiller. (< 50knots, adjustable in FSUIPC.ini) 
It gets much more complicated than that, but that is for the aircraft modeller to deal with providing a more realistic visual/tactile representation.  

[9GTurn 6]

It was indeed a double assignment.

The engine 2 reverser detent (button) on the throttle stack was mapped to "right rudder trim" under buttons and switches in FSUIPC and consequently when I taxi a twin the lever may have drifted in this zone and when landing and engaging reverersers the trim moved right and then as the rudder to nose wheel steering crossed over the aircraft went off the side.

Thanks everyone for their help.