Torpedo can be shot down and I don't expect turrets inside fighterbay, so it's still a better idea than firing them at armour, being exposed to turret fire.
500 klicks?
FS allows you to get only 750km from the center of battlefield, then you get blown up. (I'm assuming that klick=kilometer ,correct me if I'm mistaken)
And getting out of hangar before torpedo detonation should still be possible, Kilrathi carrier are long enough for it, as is Fralthi, of course Ralarrad is obviuosly too small for that, but it can be torn apart relatively easly using guns on Longbow or Thunderbolt (not to mention I will most likely want to keep my heaviest ordnance for something bigger, especially in Thunderbolt).