Military Rockets in 1930's and 1940's in Japan

摘要

The research and development of rockets in Japan had been done by the military programs. The total figures of these programs are going to show you in the Table 1. (1) Rocket Propelled shell In order to extend the ranges of shell, the research and development program was started by the Institute of Japanese Army Science and Research in 1931. In early phase, they were concerned to use the liquid motor as the booster, however finally decided to use the solid motor in order to make launching quickly. In 1932, they had done the experiments to extend the ranges using rocket effects that is installed the gun powder grain behind the shell. The experiments had done using 38 type field gun (75mm caliber and 8.2km range), It might be the first trial as the military rocket experiments in Japan. After that, it had recorded the total range of about 4km using 10cm diameter shell with solid booster which was made of black powder grain solidified by paraffin.(See Fig.1) In 1935, the research and developments of shell had been accelerated quickly according to use the new propellants compressed black powder grain. However, this new propellants was not suitable for the bigger size because of the low Isp. In 1937, the Institute of Japanese Army Science and Research had been in success to develop so-called "double base propellant". After that, they have been developed a number of rocket propelled shells as shown in Table 2. There were the several ways of propellants burning systems.