Opening throttle changes tail pitch

[jette41]

Can anybody help me to resolve this issue please?

I have a DX9 and Brain FBL system on an Align 500 DFC. Every time I open the throttle the tail pitch changes. I suspect that there is a setting/adjustment in the DX9?
I would upload a video of this happening but don't know how to

Thanks for your help.

[bigpops]

Sound like it's the Brain pre-compensating, and it's perfectly normal.

When you pile on the pitch (positive or negative) the tail has to work harder to hold. All that's happening is the flight controller is adding that pitch before the gyro senses any rotation.

[Grumpy]

Yeah, as already pointed out this is perfectly normal. The Brain by default has both collective and cyclic 'Pre-Comp' so the tail reacts to large inputs on both the collective and cyclic sticks (but more so on collective).

You can adjust this or turn it off in the Brain advanced menu. Go to 'Advanced Menu' > 'Setup' > 'Tail' and there you find sliders that adjust pre-comp for each flight mode. Best leave then on default for starters though.