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 o ...

that was torpedoed by the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

submarine USS Gurnard in the

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west of

Luzon Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...

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in the

Luzon Strait The Luzon Strait (Tagalog: ''Kipot ng Luzon'', ) is the strait between Taiwan and Luzon island of the Philippines. The strait thereby connects the Philippine Sea to the South China Sea in the western Pacific Ocean. This body of water is an im ...

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

Manila Manila ( , ; fil, Maynila, ), officially the City of Manila ( fil, Lungsod ng Maynila, ), is the capital of the Philippines, and its second-most populous city. It is highly urbanized and, as of 2019, was the world's most densely populate ...

, Philippines.

Construction

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

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and List of cities in Japan, largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, ...

, 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 tr ...

steam engine 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 the ...

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 land troops directly on shore, typicall ...

. ''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 o ...

across

southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical south-eastern region of Asia, consisting of the regions that are situated south of mainlan ...

, carrying many Allied prisoners of war (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

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