Game reads 2 forms of blackout I believe.. the 'wounded BO' leaves the A/C controllable..
But the sustained 'G' BO will 'disconnect' your controls.. you don't get the plane back till about a half second after the black fades off. You need to have been increasing the pull while in complete BO for this to occur.
My FE displays BO effects as an increasing tunnel vison to black screen a 'g' loads build. I try to keep the oppostion in the middle of that tunnel; and avoid going black screen of any longer than 1 or 2 sec to avoid control disconnect.
Hang