Ok guys, this roll, pitch and yaw stuff has made me seasick.
See, I'm working on a mod which will defy all realism and what not...
So I decided that having a Balao that could do barrel rolls would be awesome.
I played with some stuff, namely LR drag and engines RPMs with a bhp boost and now I feel ill.
I got the boat to going at a Flank x2 sort of speed while submerged and took a turn, and then the death spin began.
But as always, I won't be defeated (I was playing some quick mission.) And I attempted for 20 minutes to AUTO-target anything while my periscope was swinging across the surface for ~1s intervals. AND I don't have stabilized view.
I need dramamine.
P.S. It is possible to surface keel up. I do not recomend this.