use torp bombers and torp then when they surface. Or you can torp them when someone finds them with their sonar.

Usually 4 torps are enough to take out subs up to tier 3.
Tier 4 usually have 900 SD and are much tougher to crack.

Well the two things that work are TBs at minimum altitude and scout mines. However, these are only effective under ideal circumstances.
If you've got a bigger CV you could put HHs on it, but Bougue is like a CVE - escort carrier (in real life) and has no gunslots in NF.
Rely on your teammates to locate a nubmarine (lol) and then TB him at minimum altitude - that's what I do.
Sometimes scouts will illuminate a submerged SS , but I don't know if this is normal or a glitch.

well thanks for the info i know the sonar thing but i dont want to end up troping a friendly dds witch ive done before on accident

well thanks for the info i know the sonar thing but i dont want to end up troping a friendly dds witch ive done before on accident

for better result in hunting sub with tb, use manual, so they won't notice that they are being targeted or if in auto target them when your tb are close (not close enough that they are in your torp safety range),

for scout mines, predict where they go, and drop many mines on the direction where they go, make sure that it won't hit your ally in the progress of the game