Short and simple:
Player match, make it private, team battle, 5 min' time limit, get a buddy. Have the damage set to normal/standard, The one not going for the achievement uses the machine gun (B) to shoot his buddy on the other team until he has less than 10% health.
The guy going for the achievement needs repair drone unlocked under abilities and has to equip it after picking a plane and loadout. Now in match when the guy going for cheevo has less than 10% health he presses right on d-pad then A to activate the drone and when you get to around 50% health it should unlock.
P.S - could be dependant on the plane used; a 6/10 armour rating works and doing it on realistic damage either doesn't work or is harder.