Did this happen to anybody else / can you reproduce this bug? To see the bug in action check
Environment: KSP 0.25 32bit, downloaded via Steam Modded AND unmodded Win 7, all current updates Recipe: + 4 3.75m tanks or half-tanks connected to a centerpiece in an X-pattern like seen in the above video. + It doesn't matter if they are connected to the centerpiece directly with a truss piece as spacer or perpendicular to an X-shaped I-beam structure, parallel or perpendicular to the main structure, connected directly or docked (tried all combinations). + Bug appears not to occur with empty tanks, total mass might matter here. + SAS and RCS don't make a difference. + Happens randomly and on load from tracking station. + Catastrophic failure can be prevented by going back to the space center without saving, then reloading the flight from the tracking station (involving a certain loss of progress). I will now delete the game completely and try to replicate the bug with a completely fresh installation. Expect follow-up post this evening.