Japanese probably using American torpedo for improving their own torpedoes according to the U.S. Joint Intelligence Committee. Daily summary dated 30 March 1942

An item reported that the Japanese forces recovered (probably at Wake) an US Navy torpedo which was manufactured in 1941. Probably were technical details of the this torpedo to be incorporated in future Japanese torpedoes.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 110 dated 30 March 1942.