Japanese minelayer Minoo
Encyclopedia
was a minelayer
of the Imperial Japanese Navy
, which was in service during the final stages of World War II
. She was the lead ship
of what was intended to be a two-vessel class, but her sister ship
, designated Vessel #1822 was not completed before the end of the war.
invasion of the Japanese home islands
, the Imperial Japanese Navy perceived the need to block the entrances to the Sea of Japan
, namely the La Pérouse Strait
, Tsugaru Strait
and Tsushima Strait
to protect Japan’s long and relatively lightly defended western coastline. However, as all minelayer
s has been sunk by that time, an emergency program was begun under the Maru Sen Programme
to construct several small vessels for this task. Minoo was a modified Type 2D wartime standard cargo ship, which had been laid down by the Naniwa Dock Company on November 29, 1944. It was requisitioned by the Imperial Japanese Navy in December before completion, was launched on May 13, 1945, and was commissioned into service on August 5, 1945 after modifications at the Kure Naval Arsenal
.
, but the surrender of Japan
occurred only 5 days after her commissioning. She was removed from the navy list
on October 5, 1945.
From September 1945 through December 1946, Minoo was used as a repatriation transport, shuttling between Okinawa, Shanghai
, Hakata, and Sasebo
returning demobilized Japanese troops and civilians from the Asian mainland to the Japanese home islands. She was scrapped in 1947.
, ex-Type 2D wartime standard cargo ship, 2300 LT (2,337 t) gross
Launched at Mitsubishi Heavy Industries
-Kōnan Shipyard on 11 August 1944, completed on 2 September 1944, enlisted by the Navy on 29 January 1945, classified to auxiliary minelayer and assigned to the Minelayer Division 18 (Escort Fleet) on 10 March 1945, armaments installed on 20 April 1945 at Kure Naval Arsenal
, Minelayer Division 18 was moved to 7th Fleet, minelaying at Japanese coastal waters in June 1945, sunk by USS Spadefish
off Okushiri Island
42°43′N 139°57′E on 17 June 1945, discharged on 10 August 1945.
, ex-Type 2E wartime standard cargo ship, 870 LT (884 t) gross
Launched at Kawanami Kōgyō-Fukabori Shipyard on 22 June 1944, completed on 16 July 1944, transportation duty in Japanese coastal waters between 1944–1945, enlisted by the Navy on 6 May 1945, armaments install started at Hitachi Zōsen-Innoshima
on 9 May 1945, classified to auxiliary minelayer and assigned to the Escort Fleet on 7 July 1945, sunk by air raid at Innoshima on 28 July 1945, discharged on 22 May 1946. She was sunk before rebuilt.
Minelayer
Minelaying is the act of deploying explosive mines. Historically this has been carried out by ships, submarines and aircraft. Additionally, since World War I the term minelayer refers specifically to a naval ship used for deploying naval mines...
of the Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
, which was in service during the final stages of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. She was the lead ship
Lead ship
The lead ship or class leader is the first of a series or class of ships all constructed according to the same general design. The term is applicable military ships and larger civilian craft.-Overview:...
of what was intended to be a two-vessel class, but her sister ship
Sister ship
A sister ship is a ship of the same class as, or of virtually identical design to, another ship. Such vessels share a near-identical hull and superstructure layout, similar displacement, and roughly comparable features and equipment...
, designated Vessel #1822 was not completed before the end of the war.
Building
During the very final stages of World War II, in preparation for the anticipated AlliedAllies of World War II
The Allies of World War II were the countries that opposed the Axis powers during the Second World War . Former Axis states contributing to the Allied victory are not considered Allied states...
invasion of the Japanese home islands
Operation Downfall
Operation Downfall was the Allied plan for the invasion of Japan near the end of World War II. The operation was cancelled when Japan surrendered after the atomic bombing of Hiroshima and Nagasaki and the Soviet Union's declaration of war against Japan. The operation had two parts: Operation...
, the Imperial Japanese Navy perceived the need to block the entrances to the Sea of Japan
Sea of Japan
The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It is bordered by Japan, North Korea, Russia and South Korea. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific...
, namely the La Pérouse Strait
La Perouse Strait
La Pérouse Strait is a strait dividing the southern part of the Russian island of Sakhalin from the northern part of the Japanese island of Hokkaidō, and connecting the Sea of Japan on the west with the Sea of Okhotsk on the east....
, Tsugaru Strait
Tsugaru Strait
is a channel between Honshu and Hokkaido in northern Japan connecting the Sea of Japan with the Pacific Ocean. It was named after the western part of Aomori Prefecture...
and Tsushima Strait
Tsushima Strait
is the eastern channel of the Korea Strait, which lies between Korea and Japan, connecting the Sea of Japan and the East China Sea.The Tsushima Strait is the broader eastern channel to the east and southeast of Tsushima Island, with the Japanese islands of Honshū to the east and northeast, and...
to protect Japan’s long and relatively lightly defended western coastline. However, as all minelayer
Minelayer
Minelaying is the act of deploying explosive mines. Historically this has been carried out by ships, submarines and aircraft. Additionally, since World War I the term minelayer refers specifically to a naval ship used for deploying naval mines...
s has been sunk by that time, an emergency program was begun under the Maru Sen Programme
Wartime Naval Armaments Supplement Programme (Japan, 1944)
The was the final armaments expansion plan of the Imperial Japanese Navy .-Background:Early 1944, the IJN started building warships for war. The plan did not include any large warships which were suitable for offensive operations.-Table of vessels:...
to construct several small vessels for this task. Minoo was a modified Type 2D wartime standard cargo ship, which had been laid down by the Naniwa Dock Company on November 29, 1944. It was requisitioned by the Imperial Japanese Navy in December before completion, was launched on May 13, 1945, and was commissioned into service on August 5, 1945 after modifications at the Kure Naval Arsenal
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 Japanese home islands along with the establishment of the...
.
Operational history
On completion, Minoo was assigned to the Kure Naval DistrictKure Naval District
was the second of four main administrative districts of the pre-war Imperial Japanese Navy. Its territory included the Inland Sea of Japan and the Pacific coasts of southern Honshū from Wakayama to Yamaguchi prefectures, eastern and northern Kyūshū and Shikoku....
, but the surrender of Japan
Surrender of Japan
The surrender of Japan in 1945 brought hostilities of World War II to a close. By the end of July 1945, the Imperial Japanese Navy was incapable of conducting operations and an Allied invasion of Japan was imminent...
occurred only 5 days after her commissioning. She was removed from the navy list
Navy List
A 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 authorities of a country....
on October 5, 1945.
From September 1945 through December 1946, Minoo was used as a repatriation transport, shuttling between Okinawa, Shanghai
Shanghai
Shanghai is the largest city by population in China and the largest city proper in the world. It is one of the four province-level municipalities in the People's Republic of China, with a total population of over 23 million as of 2010...
, Hakata, and Sasebo
Sasebo, Nagasaki
is a city located in Nagasaki Prefecture, Japan. As of 2011, the city has an estimated population of 259,800 and the density of 609 persons per km². The total area is 426.47 km². The locality is famed for its scenic beauty. The city includes a part of Saikai National Park...
returning demobilized Japanese troops and civilians from the Asian mainland to the Japanese home islands. She was scrapped in 1947.
Ships in class
| Ship # | Ship | Builder | Laid down | Launched | Completed | Fate |
| 1821 | Naniwa Dock Company | 29 November 1944 | 13 May 1945 | 5 August 1945 | Decommissioned 5 October 1945; scrapped in April 1947 | |
| 1822 | Naniwa Dock Company | 1 February 1945 | 1948 | 7 June 1948 | Construction stopped in April 1945. Transferred to Inui Steamship inc., and construction restarted as merchant ship . Sunk by rough weather on 4 October 1948. | |
Approximate vessels
The IJN used two merchant ships and experimented for before building Minoo. One the Eijō Maru, other the Kōryū Maru. Their conversion was useful for Minoo. Their brief careers are below., ex-Type 2D wartime standard cargo ship, 2300 LT (2,337 t) gross
Launched at Mitsubishi Heavy Industries
Mitsubishi Heavy Industries
, or MHI, is a Japanese company. It is one of the core companies of Mitsubishi Group.-History:In 1870 Yataro Iwasaki, the founder of Mitsubishi took a lease of Government-owned Nagasaki Shipyard. He named it Nagasaki Shipyard & Machinery Works, and started the shipbuilding business on a full scale...
-Kōnan Shipyard on 11 August 1944, completed on 2 September 1944, enlisted by the Navy on 29 January 1945, classified to auxiliary minelayer and assigned to the Minelayer Division 18 (Escort Fleet) on 10 March 1945, armaments installed on 20 April 1945 at Kure Naval Arsenal
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 Japanese home islands along with the establishment of the...
, Minelayer Division 18 was moved to 7th Fleet, minelaying at Japanese coastal waters in June 1945, sunk by USS Spadefish
USS Spadefish (SS-411)
USS Spadefish , a Balao-class submarine, was the first ship of the United States Navy to be named for the spadefish. Although she was commissioned late in the war and spent only one year in the Pacific war zone, she was to run up a record of 88,091 tons in 21 ships and numerous trawlers...
off Okushiri Island
Okushiri Island
is an island in Hokkaidō, Japan. It has an area of . The town of Okushiri and Hiyama Prefectural Natural Park encompass the entire island.-History:It was the site of a powerful earthquake and tsunami in 1993....
42°43′N 139°57′E on 17 June 1945, discharged on 10 August 1945.
, ex-Type 2E wartime standard cargo ship, 870 LT (884 t) gross
Launched at Kawanami Kōgyō-Fukabori Shipyard on 22 June 1944, completed on 16 July 1944, transportation duty in Japanese coastal waters between 1944–1945, enlisted by the Navy on 6 May 1945, armaments install started at Hitachi Zōsen-Innoshima
Innoshima, Hiroshima
was a city located in Hiroshima Prefecture, Japan.On January 10, 2006 Innoshima, along with the town of Setoda, from Toyota District, was merged into the expanded city of Onomichi....
on 9 May 1945, classified to auxiliary minelayer and assigned to the Escort Fleet on 7 July 1945, sunk by air raid at Innoshima on 28 July 1945, discharged on 22 May 1946. She was sunk before rebuilt.
Books
- Ships of the World special issue Vol.47, Auxiliary Vessels of the Imperial Japanese Navy, , (Japan), March 1997
- The Maru Special, Japanese Naval Vessels No.42, "Japanese minelayers", (Japan), August 1980
- Century of Hitachi Zōsen Corporation, Hitachi Zosen Corporation (Japan), March 1985, Syllabus of Japanese merchant ships (1868–1945), Kaibundō (Japan), May 1976