Design A-150 battleship

Design A-150, popularly known as the Super Yamato class, was a planned class of battleships for the Imperial Japanese Navy. In keeping with longstanding Japanese naval strategy, the A-150s would have carried six 51-centimeter (20.1 in) guns to ensure their qualitative superiority over any other battleship they might face. These would have been the largest guns ever carried aboard a capital ship.

Design work on the A-150s began after the preceding Yamato class in 1938–1939 and was mostly finished by early 1941, when the Japanese began focusing on aircraft carriers and other smaller warships in preparation for the coming conflict. No A-150 would ever be laid down, and many details of the class' design were destroyed near the end of the war.

Background and design

In the 1930s, the Japanese government began a shift towards an ultranationalist militancy. Planners envisioned an empire stretching from Japan to the resource-rich European colonies in Southeast Asia, and defensible islands in the Pacific Ocean (the Greater East Asia Co-Prosperity Sphere). The extensive distances involved, and the likelihood of this expansion leading to a confrontation with the United States, led the Japanese to build and maintain a large fleet that could seize and hold onto these territories. The U.S. posed a particular problem for Japan, as it possessed significantly greater industrial power, and several leading members of the United States Congress had pledged "to outbuild Japan three to one in a naval race".