SS ''Dainichi Maru'' was a Japanese troop- and

Hell ship A hell ship is a ship with extremely inhumane living conditions or with a reputation for cruelty among the crew. It now generally refers to the ships used by the Imperial Japanese Navy and Imperial Japanese Army to transport Allied prisoners of w ...

that was torpedoed by the

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in the

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west of

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, Philippines in the

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at (), while she was travelling in Convoy 772 from Takaoka, Japan, to

Manila Manila, officially the City of Manila, is the Capital of the Philippines, capital and second-most populous city of the Philippines after Quezon City, with a population of 1,846,513 people in 2020. Located on the eastern shore of Manila Bay on ...

, Philippines.

Construction

''Dainichi Maru'' was laid down on 14 August 1920 at the Mitsui Senpaku K. K. shipyard in

Tokyo Tokyo, officially the Tokyo Metropolis, is the capital of Japan, capital and List of cities in Japan, most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is List of largest cities, one of the most ...

, Japan. She was launched on 21 July 1921 and was completed on 15 May 1922. She was built for the Mitsui Line and was named ''Ibukisan Maru''. She was renamed ''Dainichi Maru'' when she was bought by the Japanese company Itaya OSK Lines on 6 June 1935. ''Dainichi Maru'' was long, with a beam of and a depth of . The ship was assessed at . She had a single

triple expansion A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be trans ...

steam engine A steam engine is a heat engine that performs Work (physics), mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a Cylinder (locomotive), cyl ...

rated at 488

nominal horsepower Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. Two common definitions used today are th ...

and driving one screw. She had one funnel and two masts.

World War II career

On 15 September 1941, the Imperial Japanese Army charted ''Dainichi Maru'' for use as a

troopship A troopship (also troop ship or troop transport or trooper) is a ship used to carry soldiers, either in peacetime or wartime. Troopships were often drafted from commercial shipping fleets, and were unable to land troops directly on shore, typic ...

. ''Dainichi Maru'' participated as a troopship in Operation "M", the Japanese invasion of Lamon Bay, Philippines beginning on 17 December 1941 as the convoy departed Setouchi, Japan. The invasion force arrived at their destination on 24 December 1941 at 2 am, with the invasion proceeding without strong opposition. During the early stages of the war, ''Dainichi Maru'' would go on to complete several voyages as a

hell ship A hell ship is a ship with extremely inhumane living conditions or with a reputation for cruelty among the crew. It now generally refers to the ships used by the Imperial Japanese Navy and Imperial Japanese Army to transport Allied prisoners of w ...

across

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, carrying many Allied

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(POWs).

Sinking

On 8 October 1943, ''Dainichi Maru'' was part of Convoy 772, which consisted of five ships, including the cargo- and

and three other ships, escorted by a

torpedo boat A torpedo boat is a relatively small and fast naval ship designed to carry torpedoes into battle. The first designs were steam-powered craft dedicated to ramming enemy ships with explosive spar torpedoes. Later evolutions launched variants of ...

. At the time, ''Dainichi Maru'' was carrying 2,274 members of the 11th Independent Garrison Unit and 14th Army Workshop alongside their equipment. The convoy was attacked in the

west of

, Philippines in the

, while it was travelling from Takaoka, Japan, to

, Philippines, by the American submarine at 1.39 am after the submarine had been stalking the convoy since midnight. The ''Gurnard'' went on to torpedo and sink both the ''Taian Maru'' and ''Dainichi Maru'' in the attack. 45 military personnel and 32 crew went down with ''Taian Maru'' as she sank, while on ''Dainichi Maru'' between 2,025 and 2,057 military personnel and 32 crew were killed.

Wreck

The wreck of ''Dainichi Maru'' lies at (). The condition of the wreck is currently unknown.

References

{{October 1943 shipwrecks Steamships of Japan 1922 ships Ships built in Japan Maritime incidents in 1943 Maritime incidents in October 1943 Steamships World War II ships of Japan World War II shipwrecks in the South China Sea Shipwrecks in the South China Sea Ships sunk by American submarines