IJN Depth charge launchers
 

Revamping IJN destroyers for next release of TMO.

Seems like early on IJN DD's and ASW vessels only had DC racks, getting launchers late in 1942 and early 1943? I have not been able to locate sources with exact dates. Wondering if anyone could shed some light.

We use Imperial Japanese Navy Page TROMS for FotRSU. Use the "Long Lancers" link for the DD, of course. You can read about the class, or individual boats, and oftentimes when they did re-fit work and upgrades. Then there are the files on sites that will list the interviews post-war with some of the Japanese officers. One example is Interrogations of Japanese Officials - Vols. I & II, but there is the set of separate pdf files someone did of the Joint Army Navy Assessment Committee (JANAC) interviews that can be found peppered across the internet. It does take some digging in there though. A LOT of material.