ORIGINAL: Backwing
I'm thinking about converting a plane to have retracts, but I think the wheels would be way to close to the CG, so I got thinking.
I know this would take some design work, but...
What about mounting a weight on some type of track/slider, attached to a servo. So that when landing or taking off you could move the CG back a little with say the flap knob on the Tx. Then once up in the air, move the CG up to the regular position.
Might also be fun on a 3D plane.
If I'm reading this correctly, it sounds like you want to move the CG BACK when you land and FORWARD when you are in flight? This is reversed from what you would want to accomplish. Moving the CG back during slow speed flight will make it harder to handle. Moving the CG backward to accommodate improper gear location is not the right solution. I think the bottom line is if you can't get the gear in the right place relative to the CG, don't convert it to retracts.