Balance point???

[Stuart Porter]

Hey guys, Ive just completed my Balsa usa stearman and Im just woundering if any of you guys with experience of this model can indicate the best balance point for this model??
Cheers!

[Alan King]

Hi

what scale is this ( not that it matters really) to calculate CG for a biplane the system i use is to measure 1/3 chord top wing, one third chord lower wing, the difference in the two points due to stagger is divided in half and this gives you the safest starting point. i have used this successfully on a few biplanes and had no issues, i have actually found in two cases the manufacturers CG was so way out that the plane would be so nose heavy that flight would be impossible.

[Dave Collis 2296]

What I did with my 40% Waco is drape a string(with a weight) over the leading edge of the top wing and over the trailing edge of the lower wing, with the plane blocked up so datum line is level. This gives the total chord. I balanced at 28-30% Perfect, no trim adjustments.

Cheers,
Dave.

[Stuart Porter]

Cheers guys thank you very much for your help!!!