Do you have the SCP patch,it should work with it.
BTW i only saw that thing,i have retail...with mods.
I beleve i found the problem.In one of my ship testing mission:
\ SSD Diablo
While trying to hit a turret,for some reason it always missed,
I managed to destroy all systems under the beam,after that Hedetet started firing on different place.
Since Diablo is too strong for a fighter,see if you can order the bombers to attack those subsystems.