![Aikoku Maru-1941](https://upload.wikimedia.org/wikipedia/commons/a/a8/Aikoku_Maru-1941.jpg)
was an
armed merchant cruiser
An armed merchantman is a merchant ship equipped with guns, usually for defensive purposes, either by design or after the fact. In the days of sail, piracy and privateers, many merchantmen would be routinely armed, especially those engaging in lo ...
of the
Imperial Japanese Navy
The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...
in
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. The ship entered service in 1940, the ship was later converted to an
ammunition ship
An ammunition ship is an auxiliary ship specially configured to carry ammunition, usually for naval ships and aircraft. An ammunition ship's cargo handling systems, designed with extreme safety in mind, include ammunition hoists with airlocks bet ...
. She was sunk in February 1944 during
Operation Hailstone
Operation Hailstone ( ja, トラック島空襲, Torakku-tō Kūshū, lit=airstrike on Truk Island), 17–18 February 1944, was a massive United States Navy air and surface attack on Truk Lagoon conducted as part of the American offensive drive ...
.
Design
''Aikoku Maru'' was laid down at the
Mitsui Tamano shipyards in
Okayama Prefecture
is a Prefectures of Japan, prefecture of Japan located in the Chūgoku region of Honshu. Okayama Prefecture has a population of 1,906,464 (1 February 2018) and has a geographic area of 7,114 Square kilometre, km2 (2,746 sq mi). Okayama Prefectur ...
on 29 December 1938. The vessel measured 10,438
gross register tons, with a length of . Powered by two Mitsui B&W
diesel engine
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-call ...
s with driving twin screws, she was capable of . The vessel was launched on 25 April 1940, and was named ''Aikoku Maru'' at that time.
She was designed to be a combined
passenger liner
A passenger ship is a merchant ship whose primary function is to carry passengers on the sea. The category does not include cargo vessels which have accommodations for limited numbers of passengers, such as the ubiquitous twelve-passenger freig ...
/ cargo vessel for the
Osaka Shosen Lines's regularly scheduled services to South America. Provisionally named ''Kyoto'', the design for the new vessel was to have boasted of luxurious suite rooms. The vessel was built with large government subsidies provided from 1936 to encourage the production of large, high-speed transports and tankers, which could be quickly converted to military use in times of conflict.
Although ostensibly a luxury ocean liner, the military had a say in the design of ''Aikoku Maru'' with an eye towards its future use as a troop transport. Provision was made for
landing craft
Landing craft are small and medium seagoing watercraft, such as boats and barges, used to convey a landing force (infantry and vehicles) from the sea to the shore during an amphibious assault. The term excludes landing ships, which are larger. Pr ...
and for the anchoring of
naval artillery
Naval artillery is artillery mounted on a warship, originally used only for naval warfare and then subsequently used for naval gunfire support, shore bombardment and anti-aircraft roles. The term generally refers to tube-launched projectile-firi ...
.
Operational history
Immediately on completion on 31 August 1941, ''Aikoku Maru'' was officially requisitioned by the Imperial Japanese Navy. She was converted into an
armed merchant cruiser
An armed merchantman is a merchant ship equipped with guns, usually for defensive purposes, either by design or after the fact. In the days of sail, piracy and privateers, many merchantmen would be routinely armed, especially those engaging in lo ...
from 5 September while still at
Tamano
is a city located in southern Okayama Prefecture, Japan. The city was officially founded on August 3, 1940. As of October 1, 2016, the city has an estimated population of 60,101 and a population density of 580 persons per km². The total area i ...
, with the installation of four
15 cm/50 41st Year Type guns, two
s, two
Type 93 13.2 mm machine guns and two twin-mount
torpedo tube
A torpedo tube is a cylindrical device for launching torpedoes.
There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units (also referred to as torpedo launchers) installed aboa ...
s. She was also fitted with powerful searchlights and boom for handling a
Kawanishi E7K
The Kawanishi E7K was a Japanese three-seat reconnaissance seaplane mainly in use during the 1930s. It was allocated the reporting name Alf by the Allies of World War II.
Design and development
In 1932 the Imperial Japanese Navy requested the K ...
float plane
A floatplane is a type of seaplane with one or more slender floats mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, m ...
(with one additional aircraft as a spare).
As an auxiliary cruiser and submarine tender
On 15 October 1941, the 24th Raider Squadron (CruDiv24), consisting of ''Aikoku Maru'', , and was created under the
Combined Fleet
The was the main sea-going component of the Imperial Japanese Navy. Until 1933, the Combined Fleet was not a permanent organization, but a temporary force formed for the duration of a conflict or major naval maneuvers from various units norm ...
. ''Aikoku Maru'' and her
sister ship
A sister ship is a ship of the same class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They often share a ...
''Hōkoku Maru'' were forward deployed to
Jaluit Atoll
Jaluit Atoll ( Marshallese: , , or , ) is a large coral atoll of 91 islands in the Pacific Ocean and forms a legislative district of the Ralik Chain of the Marshall Islands. Its total land area is , and it encloses a lagoon with an area of . Most ...
in the
Marshall Islands
The Marshall Islands ( mh, Ṃajeḷ), officially the Republic of the Marshall Islands ( mh, Aolepān Aorōkin Ṃajeḷ),'' () is an independent island country and microstate near the Equator in the Pacific Ocean, slightly west of the Internati ...
at the end of November in preparation for the upcoming hostilities against the United States.
CombinedFleet.com: ''Aikoku Maru'' Tabular Record of Movement
On 13 December 1941, ''Aikoku Maru'' and ''Hōkoku Maru'' sank SS ''Vincent'' (6,210 GWT), an American merchant vessel with a cargo of rice from Australia to
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...
at . On 31 December 1941, the reconnaissance floatplane from ''Aikoku Maru'' spotted the American freighter (3,275 GWT) ''en route'' to
Wellington
Wellington ( mi, Te Whanganui-a-Tara or ) is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the second-largest city in New Zealand by me ...
. The plane failed to return, and despite searching by both Japanese vessels, no trace was ever found of the missing aircraft. The second floatplane reacquired SS ''Malama'' south of the
Cook Islands
)
, image_map = Cook Islands on the globe (small islands magnified) (Polynesia centered).svg
, capital = Avarua
, coordinates =
, largest_city = Avarua
, official_languages =
, lan ...
on 2 January 1942, and after making a strafing attack, ordered the ship to stop. After the crew of ''Malama'' abandoned ship, she was sunk at .
[Cressman, ''The Official Chronology of the U.S. Navy in World War II''; page 68] Aside from the missing pilot, there were no casualties on either side, and the sortie was concluded on 20 January 1942. CruDiv24 returned to
Hashirajima
is an island in southern Hiroshima Bay of the Inland Sea, Yamaguchi Prefecture, Japan. Located southeast of Iwakuni, it is part of the Kutsuna Islands within the Bōyo Islands group. The island covers and as of 2013 had a population of 184 ...
in February, after disembarking their 76 POWs at
Oita.
On 14 February 1942, at
Kure Naval Arsenal
was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy.
History
The Kure Naval District was established at Kure, Hiroshima in 1889, as the second of the naval districts responsible for the defense of the J ...
, ''Aikoku Maru''s four 152 mm guns were replaced by eight
14 cm/50 3rd Year Type naval guns. She was also modified to carry submarine torpedoes in her hold to enable her to function as an auxiliary
submarine tender
A submarine tender is a type of depot ship that supplies and supports submarines.
Development
Submarines are small compared to most oceangoing vessels, and generally do not have the ability to carry large amounts of food, fuel, torpedoes, and ...
. In this capacity, ''Aikoku Maru'' and ''Hōkoku Maru'' were deployed with the
IJN 6th Fleet
The was a fleet of the Imperial Japanese Navy (IJN) that during World War II, had primary responsibility for the command of submarine operations.
History
The 6th Fleet was formed on 15 November 1940, and was assigned general control of all IJN ...
on 10 March to support submarine operations off the east coast of Africa and
Mozambique
Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi ...
. At the end of March, ''Aikoku Maru'' and ''Hōkoku Maru'' returned to Kure, where CruDiv24 was formally disbanded, and they are reassigned to Subron8, operating out of
Penang
Penang ( ms, Pulau Pinang, is a Malaysian state located on the northwest coast of Peninsular Malaysia, by the Malacca Strait. It has two parts: Penang Island, where the capital city, George Town, is located, and Seberang Perai on the Malay ...
from early April, supporting submarine operations in the western Indian Ocean.
[Boyd, ''The Japanese Submarine Force and World War II''; page 90] On 9 May, ''Aikoku Maru'' captured the Dutch tanker ''Genota'' (7,897 GWT) SSE of
Diego Suarez Diego Suarez or ''Diego-Suarez'' may refer to:
* Antsiranana, a city in Madagascar formerly known as Diego-Suarez
* Diego Suarez (navigator) or Diogo Soares, 16th-century Portuguese navigator and explorer
* Diego Suárez (soldier) (1552–1623), Sp ...
, Madagascar. On 5 June, she sank MV ''Elysia'' (6,757 GWT), a British freighter carrying a number of
Allied
An alliance is a relationship among people, groups, or states that have joined together for mutual benefit or to achieve some common purpose, whether or not explicit agreement has been worked out among them. Members of an alliance are called ...
troops at . On 12 July, she captured the
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
registered freighter ''Hauraki'' near
Ceylon
Sri Lanka (, ; si, ශ්රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...
. She placed a
prize crew
A prize crew is the selected members of a ship chosen to take over the operations of a captured ship. Prize crews were required to take their prize to appropriate prize courts, which would determine whether the ship's officers and crew had sufficie ...
on board, but en route back to Japan, her New Zealander engine crew managed to sabotage the cargo and engine spares.
[
After repairs at Seletar Naval Base in Singapore, the floatplanes on ''Aikoku Maru'' were upgraded to two ]Aichi E13A
The Aichi E13A ( Allied reporting name: "Jake") was a long-range reconnaissance seaplane used by the Imperial Japanese Navy (IJN) from 1941 to 1945. Numerically the most important floatplane of the IJN, it could carry a crew of three and a bomblo ...
s, two dual Type 96 25 mm AT/AA Guns were added, and an additional 70 torpedoes were loaded. She continued to be based out of Penang until late August under the command of Tamotsu Oishi
was a career officer in the Imperial Japanese Navy during World War II.
Biography
Born in Kōchi Prefecture, Oishi graduated from the 48th class of the Imperial Japanese Naval Academy in 1920, with a ranking of 13th out of a class of 171 cadets. ...
.
From September, ''Aikoku Maru'' was assigned to the IJN 8th Fleet and tasked with transporting the IJA 38th Infantry Division to Rabaul
Rabaul () is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about 600 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in ...
for the reinforcement of Guadalcanal
Guadalcanal (; indigenous name: ''Isatabu'') is the principal island in Guadalcanal Province of Solomon Islands, located in the south-western Pacific, northeast of Australia. It is the largest island in the Solomon Islands by area, and the seco ...
. After accomplishing this mission by 10 October, her Commerce Raiding Unit was reactivated, and Aikoku Maru transited the Sunda Strait
The Sunda Strait ( id, Selat Sunda) is the strait between the Indonesian islands of Java island, Java and Sumatra. It connects the Java Sea with the Indian Ocean.
Etymology
The strait takes its name from the Sunda Kingdom, which ruled the weste ...
into the Indian Ocean on 7 November, together with ''Hōkoku Maru''.[
]
On 11 November, the raiders attacked the Dutch tanker (6341 GWT), which was accompanied by the minesweeper
A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping.
History
The earliest known usage of ...
, southwest of the Cocos Islands
)
, anthem = "''Advance Australia Fair''"
, song_type =
, song =
, image_map = Australia on the globe (Cocos (Keeling) Islands special) (Southeast Asia centered).svg
, map_alt = Location of the Cocos (Keeling) Islands
, map_caption = ...
. ''Hōkoku Maru'' was closer and attacked first, but a shot from ''Ondina''s 4-inch guns hit ''Hōkoku Maru''s starboard torpedo tube, and detonated the torpedo. A fire broke out, which quickly raged out of control, causing the aft magazine to explode, sinking the vessel. ''Aikoku Maru'' then arrived, and drove off ''Bengal'' while ''Ondina'' also attempted to escape. ''Aikoku Maru'' scored six hits on ''Ondina'' with her guns, but her two torpedoes missed. However, with their ship damaged and out of ammunition, the crew of ''Ondina'' abandoned ship. ''Aikoku Maru'' fired on ''Ondina''′s lifeboats, rescued 278 survivors of ''Hōkoku Maru'', and returned to Penang, and from there to Singapore and Rabaul. Meanwhile, the crew of ''Ondina'' managed to re-enter their ship and effect repairs, escaping to Fremantle
Fremantle () () is a port city in Western Australia, located at the mouth of the Swan River in the metropolitan area of Perth, the state capital. Fremantle Harbour serves as the port of Perth. The Western Australian vernacular diminutive for ...
, Australia.
As a military transport
From 16 December 1942, ''Aikoku Maru'' was reassigned back to the IJN 8th Fleet, primarily as a military transport to support New Guinea
New Guinea (; Hiri Motu
Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea).
It is a simplified version of ...
operations, and her aircraft were disembarked. While unloading cargo at Madang
Madang (old German name: ''Friedrich-Wilhelmshafen'') is the capital of Madang Province and is a town with a population of 27,420 (in 2005) on the north coast of Papua New Guinea. It was first settled by the Germans in the 19th century.
Histor ...
on 18 December, she was attacked in an air raid by B-17 Flying Fortress
The Boeing B-17 Flying Fortress is a four-engined heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Relatively fast and high-flying for a bomber of its era, the B-17 was used primarily in the European Theater ...
bombers of the 43rd Bomb Group of the USAAF
The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...
Fifth Air Force
The Fifth Air Force (5 AF) is a numbered air force of the United States Air Force Pacific Air Forces (PACAF). It is headquartered at Yokota Air Base, Japan. It is the U.S. Air Force's oldest continuously serving Numbered Air Force. The organiza ...
, but was not hit. She returned to Kure on 29 December 1942.[
As part of "Operation C" (the Reinforcement of New Guinea), on 5 January 1943, ''Aikoku Maru'' loaded the IJAAF 209th Airfield Battalion, 14th Aerial Repair Shop and others, a total of 691 men plus 34 vehicles at ]Pusan
Busan (), officially known as is South Korea's most populous city after Seoul, with a population of over 3.4 million inhabitants. Formerly romanized as Pusan, it is the economic, cultural and educational center of southeastern South Korea, w ...
in Korea
Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...
, arriving at Rabaul on 14 January. She was then sent to Tsingtao
Qingdao (, also spelled Tsingtao; , Mandarin: ) is a major city in eastern Shandong Province. The city's name in Chinese characters literally means " azure island". Located on China's Yellow Sea coast, it is a major nodal city of the One Belt ...
in Japanese-occupied China, arriving 24 January, and from there to Cebu
Cebu (; ceb, Sugbo), officially the Province of Cebu ( ceb, Lalawigan sa Sugbo; tl, Lalawigan ng Cebu; hil, Kapuroan sang Sugbo), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 ...
(2 February) and Palau
Palau,, officially the Republic of Palau and historically ''Belau'', ''Palaos'' or ''Pelew'', is an island country and microstate in the western Pacific. The nation has approximately 340 islands and connects the western chain of the Caro ...
(7 February), where she loaded additional troops and cargo, delivering the reinforcements successfully to Wewak
Wewak is the capital of the East Sepik province of Papua New Guinea. It is on the northern coast of the island of New Guinea. It is the largest town between Madang and Jayapura. It is the see city (seat) of the Roman Catholic Diocese of Wewak.
Hi ...
on 23 February. She returned to Kure on 5 April.[
On 10 July 1943, as part of a convoy including the ]aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...
, ''Aokoku Maru'' was attacked by the submarine north of Truk, which fired six torpedoes. One struck ''Aikoku Maru'', causing moderate damage. On her return voyage, on 15 July, she was attacked again, this time by the submarine , whose four torpedoes all missed. She returned to Kure on 2 September.[
On 6 October, ''Aikoku Maru'' returned to Tamano for repairs and refitting with additional weaponry, which included two 152 mm guns and four twin-mount Type 96s. The refitting work was completed by 31 December 1943.
]
On 21 January 1944, ''Aikoku Maru'' loaded the 629 men of the 66th Naval Guard Unit, with ammunition, supplies and construction materials. The convoy was attacked northwest of Truk by the submarine , which sank the minelayer and transport ''Yasukuni Maru''; however, ''Aikoku Maru'' was undamaged and reached Truk on 1 February. After making an abortive run to Brown Island, she returned to Truk on 16 February to find that most of the capital ships had evacuated the base in anticipation of an impending American attack. ''Aikoku Maru'' began loading ammunition and making preparations for departure to Rabaul, loading troops of the 1st Amphibious Brigade. However, before preparations were complete, Operation Hailstone
Operation Hailstone ( ja, トラック島空襲, Torakku-tō Kūshū, lit=airstrike on Truk Island), 17–18 February 1944, was a massive United States Navy air and surface attack on Truk Lagoon conducted as part of the American offensive drive ...
began, with the US Navy Task Force 58
The Fast Carrier Task Force (TF 38 when assigned to Third Fleet, TF 58 when assigned to Fifth Fleet), was the main striking force of the United States Navy in the Pacific War from January 1944 through the end of the war in August 1945. The task ...
striking at Truk with 30 air strikes of over 150 aircraft each every hour for a period of two days. On the first day, 16 February 1944, ''Aikoku Maru'' was bombed by aircraft from the aircraft carrier , with the first bomb exploding in the officer's wardroom, causing a fire. She was hit three more times in this attack, and was hit again in the second attack by a torpedo which set off the ammunition in her No.1 hold, shearing off the bow. ''Aikoku Maru'' sank in two minutes at , with most of the 945 crew and passengers.[ The aircraft which dropped the torpedo on ''Aikoku Maru''- a ]TBM Avenger
The Grumman TBF Avenger (designated TBM for aircraft manufactured by General Motors) is an American World War II-era torpedo bomber developed initially for the United States Navy and Marine Corps, and eventually used by several air and naval a ...
and its three-man crew from Torpedo Squadron 6 were also destroyed in the explosion of the ship.
''Aikoku Maru'' was removed from the navy list
A Navy Directory, formerly the Navy List or Naval Register is an official list of naval officers, their ranks and seniority, the ships which they command or to which they are appointed, etc., that is published by the government or naval author ...
on 30 March 1944.
Shipwreck
The wreck of ''Aikoku Maru'' is a popular scuba diving
Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface air supply. The name "scuba", an acronym for "Self-Contained Underwater Breathing Apparatus", was coined by Chris ...
spot in the waters of Truk Lagoon
Chuuk Lagoon, previously Truk Atoll, is an atoll in the central Pacific. It lies about northeast of New Guinea, and is part of Chuuk State within the Federated States of Micronesia (FSM). A protective reef, around, encloses a natural harbou ...
, despite her depth of approximately . The wreck is upright, with the bridge at the meter level and deck extending approximately deeper. The remains of an anti-aircraft gun on top of the aft deckhouse is often photographed, as are the scattered dishes and kitchen utensils in her galley. Her wreck was first dived by the famous French explorer Jacques-Yves Cousteau
Jacques-Yves Cousteau, (, also , ; 11 June 191025 June 1997) was a French naval officer, oceanographer, filmmaker and author. He co-invented the first successful Aqua-Lung, open-circuit SCUBA (self-contained underwater breathing apparatus). Th ...
in 1969, but she was not positively identified until later. In July 1980, a Japanese recovery team retrieved the remains of approximately 400 men who were killed in the attack, but the remains of hundreds more remain on site.[Jackson, ''Top Wreck Dives of the World''; page 127]
On 17 February 1994, a memorial monument was placed on ''Aikoku Maru''′s deck at a depth of approximately . The monument was a joint project of the Chuuk Visitors Bureau, United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
Civic Action Team (CAT), the Chuuk Atoll-based dive boat
A dive boat is a boat that recreational divers or professional scuba divers use to reach a dive site which they could not conveniently reach by swimming from the shore. Dive boats may be propelled by wind or muscle power, but are usually pow ...
SS ''Thorfinn'', and the Blue Lagoon dive shop
A dive center is the base location where recreational divers usually learn scuba diving or make guided dive trips at new locations. Many dive centers operate under the guidelines of ISO 24803, in which case the facilities must meet the ISO mi ...
at Chuuk Atoll.[Larry McLean, S.S. Thorfinn Crew and monument placer]
Notes
References
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Further reading
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External links
{{February 1944 shipwrecks
Ships built by Mitsui Engineering and Shipbuilding
1940 ships
Cruisers sunk by aircraft
Maritime incidents in February 1944
Auxiliary cruisers of the Imperial Japanese Navy
Submarine tenders of the Imperial Japanese Navy
Auxiliary ships of the Imperial Japanese Navy
Shipwrecks of Truk Lagoon
Ships sunk by US aircraft
Japanese hell ships