I think the instability was mostly because of the wind. I have moved my CG WAY back on the avistar and it always stays rock solid. 3 1/4 is the recommended starting CG for the Avistar. You would need to move it back much further than that to start making it unstable due to the CG. There is no wonder you have to land hot with the CG at 2 1/2, that is very far forward. Like I said, 3 1/4 is the starting point. You usually move back from there. How are you testing CG? Are you using the great planes CG Machine?

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