MSDF submarine’s collision with cargo ship could have caused tragedy

It was an outrageous accident that relates to the foundation of national security. The government should take more seriously the fact that one wrong move could have led to a tragedy.

The Maritime Self-Defense Force’s submarine Soryu collided with a civilian cargo ship in the Pacific Ocean off Kochi Prefecture. Three Self-Defense Force personnel were slightly injured. No one on the cargo ship was injured.

Defense Minister Nobuo Kishi apologized for the accident and stressed he “will work to prevent such an accident from occurring again.”

The accident took place in an area where many fishing boats come and go to catch bonito and other fish. The only reason there were no civilian casualties was because the cargo ship was larger than the submarine. If it had been a small fishing boat that was involved, it is unlikely it would have been able to avoid sinking.

The accident occurred when the Soryu, which had been navigating underwater, ascended close to the surface. A civilian vessel cannot detect a submarine in the water. It is the submarine’s responsibility to ensure safety.

Normally, when a submarine rises to the surface, the crew in charge of the sonar listens for the sound of the propellers of any surrounding ships to confirm their existence, their direction of navigation and the distance between the submarine and the ships.

In this case, the crew reportedly did not notice that the cargo ship was sailing nearby until the submarine ascended close to the surface of the water and they took out their periscope to see it with their own eyes. How did the crew check for ships before surfacing and how did they communicate with each other inside the submarine? A thorough investigation is needed.

The Soryu was in the middle of training after a regular inspection. The crew had been away from sea duty for a long time, and it has been argued that they may possibly have been undertrained.

Currently, the Japan Coast Guard is investigating the accident, and the MSDF has set up an accident investigation committee to determine the cause. It is important for the MSDF to cooperate with the investigation, identify the problems and disclose the details.

Another problem is that communication with the submarine was lost for about 3½ hours after the accident. The antennas and other communication devices were damaged by the accident, and the accident could not be reported until the vessel moved to a location where there were conventional cell phone signals.

If anyone had been seriously injured, the lifesaving response would have been delayed. It is a blunder that should never have happened. Communication devices such as portable satellite phones must be deployed as soon as possible.

Twenty years ago this month, nine people, including students, were killed in an accident when a U.S. nuclear-powered submarine and the training ship Ehime Maru collided off the coast of Hawaii. Many must also recall a collision between MSDF submarine Nadashio and a leisure fishing boat, which killed 30 people.

Such accidents seriously undermine the public’s trust in the SDF. All possible measures must be taken to prevent such accidents from happening again.

— The original Japanese article appeared in The Yomiuri Shimbun on Feb. 14, 2021.