Originally Posted by SideshowN
I keep on getting 10.8% damage to buildings on rescue missions. So unbelievable annoying. I fight in the air away from the buildings but buildings still get damaged. I hate this achievement. I dont know if its different on easy mode but I keep on getting 10.8% damage on normal mode. Come on game, why throw in .8% damage over and over and over. Ridiculous.
Just to keep you from getting more frustrated.
PLAY ON HARD. It brings you nothing to do on normal since you won't get the overall A-Rank.
Did you make sure not to many buildings got destroyed during the Tempest fight? I would say more than one, try again. Two or three should be fine but it makes the thing REALLY hard.
To check after the fight just leave the area and save on a different file. Go back and check how many buildings are damaged. The save is so the enemies won't damage any more buildings while you're looking around.
For the mission itself I can't give any more help than the above mentoined route I take. But a little bit of luck is involved, because the AI changes behaviour sometimes.