A word of caution regarding benign spiral dives. I have tried to establish a benign spiral set up in all my gliders, beginning with a ASW 20 and including; Nimbus 3, ASH 25, Std Cirrus, Ventus 2A, Pegasus, and most recently Std Libelle. I have been able to find a combination of flap, spoiler, and trim that will result in a benign spiral in all of them in when starting from a fairly normal attitude and in reasonably calm air. In almost every case if I attempted the manuever in moderate or sever turbulence or when in an steep turn, or from an unusual attitude the result was anything but benign. So please try it in adverse conditions, with you glider ,before attempting to descend thru an undercast or in cloud. I have Butterfly AH's in my ASH and am putting an LX S80 in my libelle, That plus practice is the best way to keep the wings on when in turbulence in clouds.