You arent supposed to fight them. Try to avoid them and if one of them manages to catch up to you then start running, wait for him to run out of air and shoot.

Fisrt, sonarman don´t work in BBs.

Some players use HH in their BBs, but for use them you will by in one this situations.
1 - There is  a FF/DD or other SS than can see enemy SS and help you to attack it with HH.
2 - If can can see enemy torpedoes maybe can guess where is the SS.

As Tapp said, you are not supposed to fight SS in your BB and apply the tactis that he mention.
However, if you have a low tier BB and your AA sucks, could mount some HH, just in case but that´s all. 

You can mount A in one part os T slots and HH in the other, but I think that will be to mant tasks to combine.

Personally for alow tier BB I try to hunt CA a smaller ships, use a scout to provide vision and, if situation allows it, sink most enemy BBs as possible.

Good luck. 

DDs and FFs dont need a sonarman to see subs so you can use one as an escort if you can deal with the escort crossing you from time to time. Also AA gunners have been given the ability to use HH guns.

It is suppose to be a rick/paper/scissor scenario with BB/SS/DD. The current problem is when there isnt an even balance among the 3 (in terms of reward).

Thanks for the replies.

Im H44 so Im just one big fat target - cant blame the subs going after me. I cant get enough speed to outrun them - they are simply to fast. Often - they are also around me in the middle of battles with enemy battleships.

My AA guys can use hedgehogs...only the H44 :

A: cant load any ammo to the hedhehogs

B: can only load two sets of naval mines (and they are pretty much useless unless you are directly over the enemy sub).

So I really have no chance aginst enemy subs unless I go for the escort ship--- and thats not really something I ever liked. Oh well - cant argue with the huge player base that seems satisfied with the way things are.

Once again thanks for the answers.

Just hope they don't know how to crit dive. If they do, the only thing you can do is use PHH to keep them in crit dive.

I would say your best weapon is your "speed". If you don't have that, well you might as well just sink and go to the next room, because it is GG for you. 

Also, another great way to fight them is to ask your subs to perform ASW.