I once made a homemade Gmetre and got up to 17 G's. I know more is possible but what's the maximum yank possible on our models? 17 is a pretty good yank and I now design my aerobatic models for 20-25 G's and this has worked well in practice. I thought I remember someone talking about calculating it but I'm short a few cells in my thinker to pull off that kind of stuff!