I’m sorry for creating a topic for this matter, but I just wanted to share something that some of You might find useful. I have just found a site, containing information about japanese navy aviation gunsights. It’s pretty basic - just the picture and short description. Maybe some of You already know this site, or have much more comprehensive sources, but adittional one won’t hurt [;)]
Well, I thought, it would be helpful for those, who are building japanese planes [;)]. There’s nothing unusual, that some gunsights are copies of german designs - Germany supplied japanese with great numer of technologies, including engines etc. E.g. one of first japanese jet fighters J8M1 Shusui is an exact copy of Me-163.
Don’t forget the DB engine copies used in the Ki 61, M6A1, & the copy of the BMW 003 for the Kikka. And the Okha engine as well. The G3M Nell was said to be based on the Junkers Ju 86. A lot of technology changed hands.