Abstract
On 15 June 1959 the Oyashio surfaced to the applause of the crew and engineers onboard: Japan completed the trials of its first post-war indigenously developed submarine. There is little English literature that explains how Japan successfully constructed the Oyashio. United States support has been highlighted, but what about Japan’s indigenous efforts? In addition, with Oyashio Japan created a World War II era fleet-type submarine, but the tear-drop hull submarine had already been developed. Why was this approach adopted and what significance did Oyashio represent? This paper demonstrates that Oyashio was primarily an indigenous Japanese effort. Japan successfully built the Oyashio because the Imperial Navy’s technological legacy continued in the form of infrastructure, personnel and know-how: there was a strong degree of continuation in Japan’s pre- and post-war submarine programs. The limited capability of the Oyashio, including its non-tear drop hull design, is explained by Japan adopting a conservative long-term approach to submarine development, prioritising the indigenisation of capability at the short-term cost of a less capable product. This approach is consistent with what has been described in broader literature as Japan’s ‘technonationalist’ approach to technology. This paper concludes that Oyashio represented an important technological and political milestone. Despite being a fleet-type submarine, the Oyashio was a technological achievement as new and old indigenous and foreign technologies were assimilated and applied lifting the capability of Japan’s submarine industry beyond pre-war levels. In addition, the development of Oyashio did not take place within a political vacuum, but in post-war Japan where Article IX of Japan’s Constitution did not unequivocally settle the position of the Japanese Self Defense Forces (JSDF). Oyashio was therefore also a political milestone as an indigenous submarine capability was reestablished during a time when the existence of the JSDF was being questioned.
Read the article online here.