The Ha-201-class submarine, (Ha-ni-hyaku-ichi-gata sensuikan) were a class of small submarines designed for the Imperial Japanese Navy (IJN). They were first deployed in 1945, but never saw combat. The Ha-201's were designed from the outset to have high underwater speed and were based on the earlier Submarine No.71 prototype. The official designation of the submarine was Sentaka-Sho type submarine.
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