Bug description:
ElevatorTrim from the SDK says:
Percentage of maximum elevator trim, linked to the SimVar ELEVATOR TRIM PCT .
The aileron and rudder I think work. I also see no examples of this being used anywhere. The only way as of right now I can set the elevator trim when loading a flight is from the Flight_Model.cfg under elevator_trim_neutral
But this forces it for all flight types. So an approach it is way off. So I think there is a bug or let us know if this is getting fixed.