How do you estimate the torque/loading on a flight control surface?

Example:
If I had an elevator that had an area of 10 sq in 2X5 & was flying at 50 mph how would I estimate the torque/resistance to movement being generated by the control surface?

If that 50 mph is airspeed, then

force (oz) = sin(angle) * area (sq in) * mph^2 / 560

hinge moment = 25% of surface chord, or 0.5 inches in your example

Torque = force * moment

So, say for 15 degrees of deflection,

Torque = 6 oz-in

If you move the hinge line back from the leading edge, you can reduce the amount of torque needed

There are online calculators that'll tell you how much servo load you have. The links to them are in the sticky threads pinned to the top of the listings. If not in this forum then over in Scratch Building.

Wellss & Bmatthews,
Thank you for the info.

My goal is to use asymmetric control surface torque to Null vectored thrust gyroscopic torque
I think I have the tools now to estimate the size & location of the control surface

I had very good results with the FSW & it's time to go totally radical