Aerodynamic Centre of an aircraft

Hi, I was wondering if there is an efficient way to determinethe aerodynamic centre of an aircraft. I set up a model of theaircraft where drag is in the Z direction and lift is in the Ydirection. I set up a grid of coordinate systems and applied GlobalGoal Torque about X at each of these coordinate systems. I washoping to find various values at each location and then run againat another angle and find a pair of values that remain constant todetermine the aerodynamic centre. The initial flow simulationhowever showed all values as being the same, as if they were aboutthe origin instead.

Is there not a way to specify torque about a point? What is thepurpose of being able to select another coordinate system indefining the torque about X? Is my only option to set the highestlevel assembly origin at only one aerodynamic centre point and runmany iterations until I find the correct point?

Note that for some reason Flow Simulation crashes when trying toselect a coordinate system at the same time as defining a globalgoal for torque. I had to define the global goals first, then editeach one after to select the coordinate system. Is this a bug?

Thanks,
Peter FerreiraSolidworksFlow Simulation