#### Tiger Tim

##### Well-Known Member

Here’s my tail surface area calculations using the method in Stan Hall’s article linked above and copying the tail volume coefficient of a J-3:

The vertical tail area is down to 7.3 square feet from the 16.7(!) I got from the other method. This new number ‘feels’ much more correct.

Curiously the horizontal tail area has actually gone

*up*using Hall’s method, from 23.2 to 26.2. Both of those still seem way too high but again I’m copying the volume coefficient of a J-3 which has a wider CG range than I think I’ll need. When I get home I’ll consult my Baby Ace D drawings to determine its horizontal tail volume coefficient, which is perfectly acceptable and I’m assuming to be smaller than a J-3s. We’ll see how that goes.