Yonai graduated from the Imperial Japanese Naval Academy in 1901 and went on to sea appointments, gunnery duties, staff service, fleet command, and naval-district command. His early sea service included the closing phase of the Russo-Japanese War. In December 1928 he took command of the First Expeditionary Fleet on the Yangtze River, placing his career within Japan's operations in China. While commanding at Sasebo, he joined the group that identified faults in the Chidori-class torpedo boats. His willingness to call the design dangerous shows a senior officer treating ship stability as a fleetwide safety problem instead of protecting institutional reputation.
Notable Point · 3:50-5:49
Technical judgement across a naval career
Yonai's rise from academy graduate to fleet and district commands includes a willingness to identify unstable torpedo-boat designs as a service-wide problem.