I have a World Models 40 size P-51 Mustang with a flutter problem with an aileron on one side only.
It is powered by a OS 70 heli on tuned pipe spinning a APC 11X8 at 16K so the plane is going faster than originally intended. I need to fix this so that it’s safe to race, this has taken me out of two events this year.

The strip aileron is driven by a Hitec HS-5475HB servo (karbonite gears). The same side has blown out the gears in one servo completely and I replaced the gear train in a different (but same model) twice because the slop was extremely excessive in the center travel area. In other words, the flutter beats the tar out of a few teeth in the gear train in just a few flights.
The control surface was dead tight with no backlash or linklage slop at the start of the flights.
I did a high speed pass level flight and out of a dive and I can’t hear the flutter over the muffled tuned pipe.
I put a gap seal on the bottom side only, no help at all.

I was offered several suggestions;

1# Up reflex the ailerons, but a some point in flight it may still flutter when the aileron is used.
2# Cut away the last 6 ½” of the out board aileron and make it part of the wing (non movable).
3# Use a servo with metal or titanium gears, eventually the servo or the aileron may still fail since the flutter is still there.
4# remove the covering on the aileron and put a thin veneer of balsa on each side to make the aileron a bit thicker than the trailing edge on the wing.
5# Add a counter weight at the out board aileron end.
6# Increase the mechanical advantage in the servo’s favor, but this will amplify any apparent gear train slop at the control surface. It’s about one to one now, the servo is slightly advantage (shorter arm).


Too many choices
What would you guys do?