Toyokawa Naval Arsenal

The Toyokawa Naval Arsenal (豊川海軍工廠, Toyokawa kaigun kōshō^?) was a major production facility for aviation ordnance, light arms, and ammunitions for the Imperial Japanese Navy during World War II. It was located in what is now part of the city of Toyokawa, Aichi Prefecture, Japan. It was one of the largest armaments plant in the Empire of Japan, but was not bombed by Allied forces until after the bombing of Hiroshima in World War II.

Plans to establish the Toyokawa Navy Arsenal were made in March 1937, along with the Suzuka Naval Arsenal in Mie Prefecture initially for the purpose of supplying 13 mm and 20 mm auto-cannons for the rapidly expanding Imperial Japanese Navy Air Service. The land was acquired in the towns of Toyokawa and Uchikubo and village of Yawata in eastern Aichi Prefecture by July 1938, and construction began on October 1, 1938. The formal opening ceremony for the new facility was held on December 15, 1939. The new plant initially covered 200 hectares, and had 1500 employees.

However, as the Second Sino-Japanese War quickly evolved into World War II, the demand for arms and ammunition increased. The Toyokawa Naval Arsenal expanded its facilities to 330 hectares in 1940. The northern 60 percent was devoted to the production of gunpowder and ammunition, and the southern 40 percent of the area was devoted to machining and assembly work, especially for the Type 92 7.7 mm aircraft gun and the Type 99 20mm aircraft cannon. In addition to aircraft weapons, the Toyokawa Navy Arsenal also produced guntō Japanese swords, bayonets, the Nambu pistol and a variety of small caliber artillery weapons as well as optical equipment such as rangefinders and binoculars.

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