Umm... I'm down here?

[Bonden]

When during the war do they become more adept and aggressive ?

[Dread Knot]

Originally Posted by Bonden

When during the war do they become more adept and aggressive ?

Roughly, about late 1943-early 1944. That's when Japanese destroyers and escorts start to routinely have radar fitted and that an effort was made by the Japanese to increase the amount of resources devoted to ASW. You start to see more proper convoys and less single ship sailings. Japanese escorts get the Type 2 depth charge with a lot more punch than the Type 95. However, it's all relative though to the IJN's lackluster beginnings in ASW. You won't be seeing any ahead-firing weapons equivalent to the Hedgehog or Squid or clouds of ASW aircraft.