RE: Servos for 1/4 scale WWI?
I believe you've got plenty of information by now. Actually, you can make your own calculation base on the size of control surface, airspeed and weight of an aircraft. You can use wing loading or dynamic pressure to get surface load in the air then combine it to static load when you have heavy surface control. Load or pressure must be multiply with the surface area to get force. Using the net of aerodynamic force and weight acted on the surface then multiply that to the distance from the pivot hinge you'll get torque load. Divide that with control arm distance to get the force acted on a linkage. Now using your servo arm you can get your required torque for your servo. To prevent your servo from overloading, you must operate within 80% of your servo capacity. Last but not the least, your servo speed determines power and its electrical equivalent.