Horizontal Stabilizer rigging

All,

Pushing 10 hours on N8PH. I note that on landing I'm using a lot less nose up trim than I did on the RV-8A. My solo CG is at 80.4" (CG limit is 78.7" to 86.82").

On today's flight I took a photo of the elevators in level flight, again solo:


As you can see the trailing edge is deflected down, indicating needed nose down trim (the elevators are adding lift).

As the CG is well forward, I assume the HS rigging is off and the HS is creating too much downward force. I installed the spacer under the HS forward spar per the plan. On the 8A I had a similar (but less significant) issue and resolved it by adding an additional 0.040" spacer under the forward HS spar.

My question - what have others experienced and what actions did you take?

I'm setting up for the test phase where I load the plane to the aft CG limit but at this point I'm concerned that I'll run out of nose up trim long before I get close to the aft CG limit.

Carl

Be careful shimming the stab.

One side effect I?ve yet to see mentioned here is that if you change the shim thickness, it will affect the alignment of the rudder hinge.

Chris

Yes, the hinge line is an issue. The last time I did this however, using a small shim, there is enough adjustment room on the rudder journal bearings to accommodate.

So right now the response to my question is that this is normal, and no one else has added a shim under the HS forward spar.

Carl

My airplane has a .250" shim. I believe stock is .125"? It's been that way for as long as I remember. I assume my Dad did it to reduce drag. I haven't noticed any real issues other than it's hard to 3 point solo.

DEM

Checked mine on flight today and elevator is in trail as best as I can tell in the mirror @ 180 mph without wheel pants. It was shimmed per plans.