A general rule of thumb is on a calm day fly the plane upright and trim it out for straight and level flight at a moderate speed.
Then roll over inverted and see if you need to put down stick input in and how much. This is the tell tale sign of your CG.
3d planes typically will roll over and fly with no input and or climb becuase of the reward CG settings we like for 3D flying.
As you move the battery back, it's going to take less input or in my case require holding some up-stick just to stay level since I like a very tail heavy setup.
Saturday, October 8, 2011
Nice rule of thumb for COG testing
mikeruth @ rcgroups: