Quoting Smithsonian National Air and Space Museum | Aichi M6A1 Seiran (Clear Sky Storm): Aichi chief engineer, Toshio Ozaki, designed the M6A1 Seiran to fulfill the requirement for a bomber that could operate exclusively from a submarine. Japanese w This Vertical Jump program is a little known multi-faceted vertical jump training program that provides trainees with all the
Aichi M6A Seiran. The new submarines and aircraft were assigned to the Japanese Imperial Navy's 1st Submarine Flotilla, comprising the two STo submarines, the I-400 and the flagship I-401, each carrying three Seirans together with two type AMs, the I-13 and I-14. The 1st Submarine Flotilla commenced training with the Seirans in January 1945, the crews gradually learning how to handle the submarines and aircraft.