Just a question : does destroying weapon subsystem of cruisers (or destroyers) make the turrets disable ?
I read in the walkthrough of "Good Luck" mission, the last of the FSport campaign, that if I destroy the weapon subsystem of the Lucifer, she cannot shoot down the Ursas, but even I destroy this subsystem, her turrets still shooting my Ursas

[The best strategy, however, and one that becomes necessary on the higher difficulty levels, is to follow your wing's lead and destroy the Lucifer's weapons subsystem first. This will prevent the Lucifer from shooting down Delta wing's bombs]