Counterbalancing the rudder. "The key here is not that we're trying to make the nose of the surface hang downwards (well, we are, but gravity is not the issue), but rather than we're trying to move it's inertia (it's center of mass) to be forward of the hinge line, so deflections of the structure to which it's attached make the surface move to generate aerodynamic forces which DECREASE the load which made the structure deflect in the first place.  It's the same for a wing/aileron, a stabilizer/elevator, or a fin/rudder.  We just use gravity to help us measure where the center of mass is.  It doesn't matter whether the surface is used horizontally (ailerons and elevators), vertically (rudders), or otherwise (ruddervators on a Bonanza, for example). As an exercise to the curious, why don't we balance flaps?

 

This makes since and makes me ask the same question I asked myself a week ago. Wouldn't it be more affective to preload springs at the top and/or the bottom of the rudder so as to increase the spring load in the opposite direction of rudder movement and reduce the other spring's load in the same direction as the rudder's direction of movement? However, this would adversely affect rudder pedal feel/load.  I'm going to install the weight, but the thought process is interesting.

Craig Berland