after targetting (with b, SubUnitTargetKey) and destroying a turret, if you're lucky your current target will revert to the main ship. If you're unlucky, it will be some other nearby ship.
In any case, if you select the ship with turrets again, and hit 'b', your target will be the still-exploding turret momentarily, and then it will be whatever it switched after blowing up that turret. Only after the turret finishes its explosion animation (> 1 second!!!) can you target another turret. I found myself blowing up a turret, waiting for it to finish blowing up, then pausing the game to figure out what turret to target next.
This totally precludes taking out multiple turrets with a single firing of heavy masers (4s beam), which would be possible if targetting switched to the next active turret on the side of the ship exposed to you. (and you were quick with the 'l' key to lock the target, which seems to be required for your shot to actually do damage...)
I almost marked this as a "game-stopper", because turret targetting is so bad that it makes fighting capships not much fun.
Anonymous