Today I played around a bit with
Post Meridian, giving my copilots Kents and flying different kinds of bombers myself in an effort to save the UEC Vilnius. After several tryouts I indeed managed to save the cruiser with 2% hull integrity remaining. I flew an Uriel with Beta wing keeping my back secured.
Now there I wonder how people manage to save the Vilnius in that mission without manipulating it in FRED which is said to be possible. To save it you have to destroy all of Meridian's secondary beam cannons plus the Juarez's beams. In my eyes totally impossible with a hand full of Uhlans and copilots that won't take orders from the player.
Plus, I realized that the loss of the Vilnius is mourned in the debriefing even if you save it. So the bonus goal should probably be removed. Instead you could add a secondary or bonus goal for destroying all the Meridian's escorts, which is indeed possible under normal conditions (meaning without changes made in FRED).