Rob since you're in 1944 I would suggest caution. The Destroyers are deadly from 1943 onwards. I would fire as many torpedoes as possible to as many targets as possible from the largest possible distance to avoid detection. In situations like these there is a high chance you will get yourself killed if you try to get too close. If despite all this you still want to go for the kills try to fire a couple of torpedoes to the most important ships. Be prepared though to get a heavy beating afterwards if you get detected by the DDs.
Good Luck
