Incidence adjustment for trim

So Bob, you get the gold star. They zero’d the wings. No good. Then they started adjusting the washout. No good. Also did some aileron “adjustments” by bending. No good. Snapped into a spin to the right from 1 G stall with the ball centered. Decided to go back to zero and it turns out the aileron adjustments won the day. Still needs a little rudder tab adjustment but it flies straight and doesn’t spin out of a power off stall.
 
Do you know how they adjusted them? Before I discovered the hinge line problem on the Cubs I tried foot long trim tabs, munching the trailing edge, making a jig to adjust aileron wash (yes, there is a slight washout on a Cub aileron, and yes, it involved lots of re-riveting) - none of that worked.

For Cubs, we just order a matched pair. Expensive, but it works. Stalls then become benign.
 
By grabbing a handful of trailing edge and bending up or down to even out the ailerons in flight, working from one end to the other. A very small change makes a big difference. He did share they’ve improved their process in building these ailerons in the last year or so and that they have to do less of the laying on of hands. Met one of their test pilots. He said there are usually multiple flights up to around 1.5 hours total time tweaking things after they roll off the line adjusting washout and ailerons and the rudder tab.
 
Derek Lawless said:
By grabbing a handful of trailing edge and bending up or down to even out the ailerons in flight, working from one end to the other. A very small change makes a big difference. He did share they’ve improved their process in building these ailerons in the last year or so and that they have to do less of the laying on of hands. Met one of their test pilots. He said there are usually multiple flights up to around 1.5 hours total time tweaking things after they roll off the line adjusting washout and ailerons and the rudder tab.
Click to expand...
From the ACA website:
  • Adjust by bending the ailerons trailing edge in the same direction as displacement.
    • Use both hands to apply gentle, even pressure.
    • A small twist creates a large change.
    • If necessary, use a wide flange tool near aileron ribs for extra leverage. - vise grips sold as
 
Derek Lawless said:
From the ACA website:
  • Adjust by bending the ailerons trailing edge in the same direction as displacement.
    • Use both hands to apply gentle, even pressure.
    • A small twist creates a large change.
    • If necessary, use a wide flange tool near aileron ribs for extra leverage. - vise grips sold as
Click to expand...
The other thing I learned is the elevator cable tension should be measured with the elevator in the full down position. If measured inline with the horizontal stab the tensions will be way off spec.
 
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