Originally Posted by AOS Puck
You need to pay attention to the mission to find out what requirements there are. There are three basic things:
Amount Of Damage Taken (Less damage taken, more points for you)
Ammunition (Less ammo used, more points for you)
Time (Quicker you finish, more points for you)
All missions use one to all three of those requirements in order to figure out your Rank. At the end of a mission just look to see what requirements are being used for that mission and adjust your gameplay accordingly.
Edit: Apparently the mission you are having trouble with is based on Damage and Time.
Just edit your mech and weaponry so that you can do quick damage and not sustain a lot of damage. By the way, those numbers above are what you need to obtain Rank S for Normal & Hard difficulties.
as a matter of fact for dat mission..i suffered 0AP dmg..i used only lik 20k of ammo and 189secs..all 3 requirements are under the threshold..still no S rank!!