I have been looking at DamienB's pics of the Old Warden Autumn Show.
http://www.pprune.org/forums/showthr...hreadid=104583
What appears to be the aileron mass balance looks like a sickle shaped mini wing with anhedral tips.
The 5th pic from the top shows this well
Is my supposition correct and if so, why is it like this instead of the usual streamlined blob of lead ?