>>626779
wow! thank you for making these available. your post got me curious so i searched around and discovered that he passed away only just late last year. He continued making paper planes in retirement as the president of the japan paper plane association which holds tournaments across japan. he also contributed to a children science magazine sharing his knowledge and designs until 2016.

this has the final article published in the magazine in 2016
https://www.kodomonokagaku.com/read/67662/

his wiki in Japanese has loads more information than the English one
https://ja.wikipedia.org/wiki/%E4%BA%8C%E5%AE%AE%E5%BA%B7%E6%98%8E

A release from jppa on his death
http://www.kamihikouki.jp/news-detail.php?id=119&s=09

the last paper plane cup he attended before his death
https://www.youtube.com/watch?v=m9OVEQosvNw

i think i have a scan of jet age jamboree but i need to find it. if you want more info just look up ninomiyas name in Japanese (二宮康明).