Those pirates aren't plot-related, so what you can do is jump in, kill a few quickly, jump out before you die, rinse and repeat. They won't respawn before you can eventually kill them all, and if they do, chances are they'll respawn in a distant pirate sector. In short, whittle them down bit by bit, and you should be clear to finish the mission.
I'd suggest putting FLAK on your Titan everywhere you can and wiping out the fighters first. When they're gone, use capital weapons to kill off any big ships. Missiles always go over big, too. In fact, if you have an M7M loaded with flails and hammers, that may be a better choice than the Titan. Anyway, good luck.