The submarine “Canglong” of the Japanese Maritime Self-Defense Force collided with a merchant ship off the coast of Ashika, Kochi Prefecture on the 8th, causing the submarine bridge to be skewed and the shell rudder to break.
Kyodo News Agency of Japan learned from relevant people in the Ministry of Defense on the 9th that the accident may be caused by the human error of the submarine’s sonar confirming that the surrounding situation was insufficient.
According to the report, usually a series of procedures need to be performed before the submarine floats: confirm whether there are other ships around by sonar, and ensure that no dead angles are detected by changing the direction of the submarine, and then rise to the periscope near the sea in stages to extend the periscope, and the crew can observe the sea surface.
According to relevant people from the Ministry of Defense, the “Canglong” failed to confirm the merchant ship with sonar during the upsurface, and was only discovered when she stretched out a periscope near the water surface.
According to analysis, due to its close proximity, the “Canglong” had no time to avoid it.
The upper part of the submarine and the bottom of the merchant ship had collisions, causing many damage to the submarine.
Due to the damage to the submarine’s antenna, it takes more than 3 hours from the accident to the report, and the Self-Defense Force will study the mode of submarine communication in emergency situations in the future.