Hawaii researchers with the Hawaii Undersea Research Laboratory found one of the largest submarines captured by the U.S Navy at the end of WWII, according to CNN on Dec. 3. The Japanese submarine, known as a Sen-Toku class submarine, was brought to Hawaii and later scuttled by the Navy in 1946 to prevent the technology from reaching the Soviet Union.
The 400-foot long vessel is basically an underwater aircraft carrier that holds three seaplanes, each capable of carrying an 1,800-pound bomb. The vessel was also capable of reaching any point on the globe without the need to refuel, according to CNN. It's understandable why the United States wouldn't want this to fall into the wrong hands.
The design of this submarine marked a shift in the design of submarines, which were seen as weapons. After the I-400, submarines were given the ability to launch missiles. This submarine, one of three of it's kind ever built, was the largest submarine until the 1960s saw the arrival of the nuclear ballistic missile submarines.
Though the submarine was found back in August of this year, the lab first had to notify the U.S. State Department as well as the Japanese government before altering the public.
In total, five submarines—the three Sen-Toku subs and two fast-attack subs—were captured from the Japanese and later scuttled. So far, four have been located.