Nakajima Aircraft Company
Born in Tokyo, Itokawa skipped grades in school and graduated from the Tokyo Imperial University in 1935, having majored in aeronautical engineering. In 1941, he became an assistant professor of the Imperial University of Tokyo. During World War II, he was involved in designing aircraft at the Nakajima Aircraft Company and designed the Nakajima Ki-43 "Hayabusa" ("Peregrine Falcon"; Allied reporting name "Oscar") fighter.