I posted this on the ARF discussion but most persons building ARF's probably do not have to figure the CG. This AT6 has been nothing but truble and I hope to learn by making it easy to land. Hope someone can give advice. Thanks.

The manual for this AT6 calls for 3.5 to 4 inches from the leading edge to the CG. This plane snaps on landings unless I burn it in. Since we have a short runway I built in flaps and barn door ailerons. That did not help. I have now stripped the wing and built in 3 degrees of washout. It is about ready to go and so I wanted to be sure about the correct CG.

Now I am confused! My calculations show the CG to be only 2.5 from the leading edge. So to be sure I drew the wing on graph paper and it also shows 2.5. This figure is 25 percent of the MAC. One panel of the wing is 29 inches span. The root rib is 10.5. And the tip rib is 7.5. There is a leading edge sweep of about 3 inches.

I would love to have somebody else calculate the MAC and CG to either agree or disagree with my calcs.

Thanks, Arno

http://www.geistware.com/rcmodeling/link.htm try this it works pretty good

Thanks, I can use that calculator. Although I did finally get the CG figured out. In the end it came out where the manual said. What fooled me was that the front of the AT6 win just squares off and goes straight across the fuselage. I put a straight edge along the tapered wing leading edge and found the gap to be one inch at the fuse. After I added that to the root chord, my calculations came out the same as the manual.

The reason I got so involved with the CG was that the plane seemed to be too nose heavy using the manual info.