About the Japanese I-400-class Japanese Navy Submarine
Three special attack aircraft "Seiran" can be installed, and it is also known as a submarine aircraft carrier.
The three submarines that entered service during World War II are still the world's largest diesel-powered submarines today.
Theoretically, it boasted a long cruising range of being able to navigate the earth once and a half, and was able to attack from anywhere in Japan to anywhere on the earth and return to Japan as it was.
In Japan, three ships of the same type entered service, but they all ended before the concrete results were achieved, and the Allies didn't even know they existed until Japan surrendered.
There is an anecdote that when the US military investigated the I400 immediately after the end of the war, an American officer was astonished by its size.
After an investigation by the US military, the i400 was subjected to torpedo disposal off the coast of Hawaii. Then it was discovered by American researchers at the bottom of southwestern Oahu in August 2013.
Drainage basis 3,530 tons underwater 6560 t
Total length 122m
Full width 12m
Cruising distance 37500 nautical miles
Crew 157 people