The photo shows the head submarine of the series I-400 the day after the surrender to the Americans.
Japanese submarines of the I-400 series were the largest submarines before the appearance of atomic submarines. The design was started by Admiral Yamamoto, who needed a submarine aircraft carrier capable of carrying seaplanes armed with an 800-kilogram bomb or air-torpedo. The aircraft was Aichi M6A “Seiran” (Mountain haze). Of the 18 U-400 submarines planned to be built, 3 were completed, but they also did not take part in the fighting.
Date: August 28, 1945