An accident in which a sightseeing boat sank off the Shiretoko Peninsula in Hokkaido, killing 14 passengers and missing 12 people will take one month in 23 days.

The scope of the search has expanded over time, but the search has been difficult as no missing persons were found at the end of the 28th of last month.

So far 14 people have been found 12 people are missing

The first missing person was found on the morning of the 24th of last month, the day after the accident.

Ten people were found in the sea and rocky areas around Cape Shiretoko, about 14 km northeast of the Kashni Falls at the site.

On the same night, one was found at sea about 14 kilometers east of Cape Shiretoko, farther from the scene.

Furthermore, on the 28th of last month, the sixth day after the accident, a total of three people were found on the sea about 23 to 24 km south-southeast of Cape Shiretoko, and they were washed away from the site to the offshore of Rausu Town on the opposite side of the Shiretoko Peninsula. rice field.

[Drift range is expected to be wide]

The waters around the Shiretoko Peninsula are originally fast and complex, and it is predicted that if passengers drift over the sea, they will already be widespread.

According to Associate Professor Naoyuki Inukai of Nagaoka University of Technology, who is a director of the Water Difficulty Society and specializes in wave analysis, the range of drifting may extend to a wide range around the west and north sides of Kunashir Island in the Northern Territories. Is that there is.

In fact, in May, the Russian side contacted Kunashir Island that two bodies had been found so far, and the Maritime Security Headquarters is proceeding with confirmation that it may be a passenger or crew member of a sightseeing boat.

In addition, Associate Professor Inukai said that the range of drifting had expanded to the northwestern sea area due to the influence of the subsequent wind, and it is possible that it had spread to the Sea of ​​Okhotsk at least 190 km north of the tip of the peninsula by the 10th of this month. I point out that there is.

[No clues found on board]

On the other hand, even for a tour boat that sank to the bottom of the sea at a depth of about 120 meters, a search was conducted with an unmanned aerial vehicle equipped with an underwater camera to check if there were any people left behind.

In addition, last week, for two days, salvage company divers searched the interior of the dive in a way that could accommodate deep waters called saturated diving, but found no clues.

The Japan Coast Guard Headquarters and the Self-Defense Forces want to expand the range to the waters around Kunashir Island and continue searching at sea to hurry to find the missing person.

Expert "Search required around Kunashir Island"

A saturated diving search was conducted on the sunken ship last week, but no clues were found that could lead to the discovery of the missing person.

Regarding this, Junji Toyama, an alumnus of the Japan Coast Guard and a managing director of the Marine Rescue Japan, said, "Passengers may have escaped by wearing life jackets before sinking, but it has been too long since the outbreak. The search for the is also expected to be difficult. "

On top of that, if the passengers are drifting, it is highly likely that they have already been washed away, so Mr. Toyama said, "Searching around Kunashir Island in the Northern Territories is essential, and contacting and coordinating with the Russian side. Information sharing is very important. "

According to Mr. Toyama, the Japan Coast Guard makes full use of the simulation of drift prediction that it operates independently, and is searching while deciding the arrangement of the ships to be searched.

Whereabouts of future investigation

The 1st Regional Coast Guard Headquarters continues to search for missing persons and works on two people, Seiichi Katsura, president of the Shiretoko Tour Boat, which operates KAZU 1, and Captain Noriyuki Toyoda, whose whereabouts are still unknown. We are proceeding with an investigation on suspicion of being fatal due to negligence.

[Focus 1 Pros and cons of making a decision to set sail]

One of the focal points of the investigation is the pros and cons of deciding to sail on the day of the accident.

On this day, it was expected that the weather would be stormy in Shari-cho from the afternoon, and strong wind warnings and wave warnings were issued by 10 am.

President Katsura admitted at a press conference on April 27 that he knew the possibility of rough weather, and explained, "I consulted with Captain Toyoda and decided to return to the sea when the sea was rough." Did.

However, the company's operating standards, which were subsequently revealed, stipulated that the departure should be canceled if the wave height is 1 meter or more and the wind speed is likely to reach 8 meters or more.

[Focus 2 Did safety management problems cause accidents?]

Another focus is whether the company's safety management issues were the cause of this accident.

The company had to be informed about the passing time, weather, wave height, etc. every time the tour boat arrived at the designated point of the navigation route, but on the day of the accident, such communication was not done. It was.

President Katsura, who is the flight manager, had to stay in the office while the ship was out, but on the day he was away from the office and contacted other employees with the captain to understand the navigation situation. It means that he did not give any instructions to do so.

In addition, the sunken "KAZU 1" had a satellite phone out of order, and the captain's mobile phone was out of the calling area for most of the navigation routes, so he left with insufficient communication means. There is also suspicion.

The point is whether or not such a sloppy safety management system can be said to be the cause of the accident.

The 1st Regional Coast Guard Headquarters will start to identify the cause of the accident, such as withdrawal of the ship, and will also listen to the situation voluntarily from President Katsura to investigate the circumstances of the decision on the operation and the actual situation of safety management. I have decided.

Expert “Hull salvage, identification of the cause of the accident is the most important”

We asked Mr. Toyama about the points of future investigations.

Toyama points out that it is most important to pull up the sunk hull and investigate it in detail to identify the cause of the accident, as no survivors have been found.

In this accident, before the ship sank, the tourist boat reported 118, such as "the bow was flooded" or "the engine could not be used".

Mr. Toyama pointed out, "It is necessary to find out how the water got into the ship and why the engine stopped. The investigation will identify who made the mistake." increase.

He also said, "If you pull up the ship, you can see the time of sinking from the clock that stopped. If you analyze the smartphone of the leftover item, you may be able to identify the course that the ship followed."

Furthermore, regarding the fact that the ship departed in anticipation of bad weather, "Who made the departure and what kind of judgment was made, why it was not possible to make a decision to return quickly when the sea broke, the company's safety management regulations, etc." I think we can proceed with the investigation on those points as well. "