NAHA - An extensive deep-sea investigation has revealed new details about the final moments of the Tsushima Maru, a wartime evacuation ship that sank during World War II, uncovering two critical points of damage that led to its rapid sinking in just 10 minutes.
A survey vessel set out last year in waters off Kagoshima Prefecture near Akusekijima, deploying unmanned submersibles to explore the seafloor as part of a memorial project marking 80 years since the end of the war, with the goal of examining the Tsushima Maru, which lies at a depth of 870 meters.
In 1944, following the fall of Saipan, the Japanese government anticipated that Okinawa would be next and initiated a large-scale evacuation, placing schoolchildren aboard the Tsushima Maru, which was later torpedoed by a U.S. submarine on the night of August 22nd and sank while transporting civilians as part of military logistics, resulting in 1,484 confirmed deaths, including 784 children, making it one of the most devastating maritime tragedies of the Pacific War.
For decades, the circumstances surrounding the sinking remained unclear, even as memorial visits were made by members of the Imperial Family, while bereaved families continued to seek answers and the return of remains.
Among the few survivors is Masashi Takara, now 85, who was just four years old at the time and credits his survival to his father, who held him for three days before succumbing to exhaustion and sinking into the sea, while Takara lost nine siblings and both parents, with only he and one sister surviving.
In the years following the war, the Japanese government imposed strict censorship, preventing families from even mourning openly, as evidenced by a letter written by an older brother to relatives in Okinawa warning that the sinking must not be disclosed to neighbors, reflecting fears that public knowledge of the tragedy would hinder evacuation policies aimed at preparing for a mainland battle.
For many years, families did not even know the exact location where the ship had sunk, until a government survey in 1997 confirmed the wreck on the seabed, offering some measure of closure, although hopes of recovering remains were dashed due to the extreme depth.
Determined to preserve the memory of the tragedy, survivors and families established a memorial museum, yet their desire to recover personal belongings and remains never faded, believing such items carry the spirits of the deceased.
Takara revisited the area in southern Kagoshima where he was believed to have drifted ashore, reflecting on the loss with deep emotion, aware that time was running short.
In November last year, a large-scale survey was conducted for the first time in decades, backed by a budget of approximately 100 million yen, utilizing advanced unmanned vehicles equipped with high-definition cameras capable of reaching depths of 2,000 meters, along with robotic arms designed to retrieve artifacts.
The survey also incorporated 3D imaging technology to reconstruct the wreck and analyze the damage, with family members watching live footage transmitted from the seafloor.
At a depth of 870 meters, the submersible captured images of the ship’s hull, including clearly visible lettering, prompting emotional reactions from observers who described the experience as akin to seeing the faces of the deceased.
Efforts were made to recover items from the seabed, but harsh conditions and the passage of 81 years meant that most personal belongings had either been swept away or buried, although some materials believed to be part of the vessel were retrieved, along with sediment from the seabed in hopes it might contain human remains.
Analysis later confirmed that the recovered items included wood and metal fragments from the ship, but no bone material was found in the sediment.
The investigation identified two major holes in the hull, one near the bow and another toward the stern, each measuring roughly 10 meters wide and 7 meters tall, with evidence suggesting that torpedoes struck both locations, causing explosive damage that forced the hull outward.
A fallen mast was also identified near one of the impact sites, supporting the conclusion that internal explosions contributed to the structural failure.
Based on 3D reconstruction, researchers concluded that seawater rapidly flooded the vessel through these breaches, causing it to lose buoyancy and sink within approximately 10 minutes while many children were asleep, with the ship ultimately resting tilted slightly to the left and facing toward Kyushu, the intended destination of its passengers.
Although the survey did not recover remains, it provided long-awaited clarity and a sense of closure for families, who expressed appreciation for the government’s efforts to finally confront the tragedy using modern technology.
More than 60,000 crew members are believed to have died in attacks on ships during the Pacific War, many of whose resting places remain unknown, and survivors like Takara emphasize that the Tsushima Maru should not be remembered in isolation but as part of a broader history of unresolved wartime losses, urging continued efforts to locate and honor those still missing.
Source: TBS
