I'm looking to map the big left/right rotary knob atop my X52 to the rudder trim axis. I have the lower knob set to the elevator trim axis and it works excellent. Slider controls the flaps. Now, the rudder trim axis isn't accessible through the control window in the sim so I edited the controls file using information from this post. Here's the assignment: <Axis> <AxName>RyAxis</AxName> <Index>4</Index> <AxEvent>RUDDER_TRIM_SET</AxEvent> <AxScale>127</AxScale></Axis> I copied the assignment for the elevator axis and just changed the AxName, Index and AxEvent. I've confirmed "RyAxis" is indeed the correct name but neither RUDDER_TRIM_SET or AXIS_RUDDER_TRIM_SET has any effect on the rudder trim wheel in my aircraft. I don't have FSUIPC, though I'm not against buying it if it'll get this to work as I know it does a lot of other useful things too Thanks in advance!

DrewThat looks OK - I guess that you assigned it in the current "standard.xml" (ie the one in the users\appdata\roamimg\FSX\controls) and it is entered under the Saitek X52 Flight Control System {xxxxxxxxx} section? One thing to try is to use RvAxis instead of RyAxis.I can confirm that you can assign this axis in FSUIPC4 to rudder trim if you use 'Axis assignment'/ 'Send direct to FSUIPC calibration' option.Neither aileron trim or rudder trim seem to be available as options in FSX.RegardsPeterH

No joy, thanks tho. I'll get around to picking up FSUIPC soon