I have a Enya SS40 powered Wot4, a symetrical wing, first aerobatic plane, fairly light.

I want to replace the single servo controlling both ailerons with 2 individual servos. We have a short downhill strip and running off the end on landing is always a problem that the guys with flaperons/spoilerons don't suffer. (they are probably better pilots too).

I have bought 2 Topaz mini servos rated at 1.8Kg/cm, thinking the pair of them would be close to being a replacement for the existing std servo. Std servos are in the 4-5kg/cm range, so I figured that 2 x 1.8=3.6 would be pretty close.

Until I got them home and took them out of the box and they are TINY!
Now I'm not so sure I want to entrust my plane to them.

How can I decide if they are going to cut it or just strip the gears? I figure there is a considerable safety margin in a std servo, and I'm only recently off my trainer, so I won't be going ballistic with it.

Short of driving down the road at 50mph with the wing out the window and a spring scale attached to the the aileron control arm, I can't see how I can make an informed judgement.

Does anyone know of a formula that would allow you to predict the pressure exerted by airflow on a fully deflected aileron?

Ailerons are 60cm (24") x 4cm (1.5") each.

Any suggestions much appreciated.
Thx