Talk:Recent Updates/@comment-104.238.63.92-20190803110411

The Japanese did have ASW mortars during the war an 81mm carred on escorts and a 150mm carred on merchants and transports, there was also a 150mm rocket propelled depth charge developed but the war ended before it was deployed.

http://www.navweaps.com/Weapons/WAMJAP_ASW.php

https://en.wikipedia.org/wiki/Type_97_81_mm_infantry_mortar