ddekel, you say my explanation is totally wrong but then go on to pretty much repeat what I just said using a lot of fancy terms and force names.....
Originally posted by ddekel
....dihedral do not roll back the A/P !!!
it's just create a Croll_beta derivative (Rolling moment coefficient due to side-slip).
That means, It couples between yaw and roll.
Having a sudden gust, A/P sideslip and then dihedral causes
a roll moment into the turn !!!
what happens is that beta angle (sideslip) become alfa.
Dihedral actually elimnates sideslip by turning it into alfa angle,
and this is a real directional stability.
finally the A/P rolls back due to it's low C.G position,
this has nothing to do with dihedral.......
And as for your last statement I've flown a couple of low wing models that have some dihedral and the still show a tendency to roll back to level when disturbed or when the controls are neutralized at the end of a turn without actively leveling the model. A low CoG will certainly help to level the wings thanks to the pendulum action but I've got first hand proof that neutral or even high CoG's will self level also.