Japan invented a new kind of submarines according to the Dutch newspaper De Tijd dated 21 December 1932

An item dated Tokyo 20 December reported that Japanese naval experts designed a complete new kind of submarine who was to operate before the main fleet to prevent the danger of torpedo attacks. Experts stated that this design was unique and that now other powers possessed such vessels. With a displacement of just 500 tons they could developed a very large speed. In times of war they would cooperate with planes to locate the positions of submarines of the enemy. As soon as the Diet approved the budget for next year would two of this ‘sea wolves’ be laid down. The needed money would be paid out of the supplementary budget of 10 million guilders approved by the department of finance for the new building of ships.