I don't run.
If I'm leaving a fight at all, I'm either damaged beyond being "helpful" or out of ammo. I will fight while on fumes, pilot wounded. This is a game, I've lost count of sorties where I've had a lot of kills, turned back to help and gotten shot down. I play for competition. I've also lost count of 5 on 1's I've walked away from - "shaking and mentally exhausted from being on the hats".