how to know when you went way back in the C.G

and if manual gave a range can you still go even farther

please answer

talking about all planes in general</p>

A neutral CG 3D plane will not climb or dive when inverted with the elevator at center.

okay thanx
but what i mean if the range in the manual is from 100 to 110

and i balance it to 115, is it okay?

Every model is going to be different. If your fuel tank is on the CG you need to be really careful. If your fuel tank is in the nose, it gives you a little margin for error. Taking off with a full tank will help with nose weight. So if the plane starts to act tail heavy as it burns fuel you know it is to tail heavy.
If it was me doing it. I would add some temporary weight to get the CG at 110 and put a few flights on it. Then, if you are comfortable with the handling, try it without the weight. Keep in mind also that a rearward CG can make a plane very hard to land. I have owned one that every landing was like a harrier. It made every landing a controlled crash.

David

thanx for your help

yes you can move the cg back if you want too the recommended ranges are a good starting point to get the plane to fly. Where you finally put the cg is where you want it for your preferences and ability. some people want neutral aircraft and some want to slug the tail. Just be aware that moving the cg back or faorwards will effect the flight characteristics of the plane, do what feels good for your flying

Thanx
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