''Wa-1'' (''Japanese:'' 第1号掃海特務艇) was the first No.1-class auxiliary minesweeper 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 ...

during

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 ...

History

''Wa-1'' was the first of 22 No.1-class auxiliary minesweepers built for the

. Sources differ as to whether the class had wooden or steel hulls. The design was based on that of a

fishing trawler A fishing trawler is a commercial fishing vessel designed to operate Trawling, fishing trawls. Trawling is a method of fishing that involves actively dragging or pulling a trawl through the water behind one or more trawlers. Trawls are fishing ...

and readily convertible to a fishing vessel after the war. She was laid down on 30 June 1941 at the Ōsaka Iron Works shipyard in the Sakurajima district ( :jp:桜島 (大阪市)) of

Osaka is a designated city in the Kansai region of Honshu in Japan. It is the capital of and most populous city in Osaka Prefecture, and the third most populous city in Japan, following Special wards of Tokyo and Yokohama. With a population of 2. ...

. She was launched on 9 November 1941, and completed and commissioned on 31 January 1942. She was assigned to the

Yokosuka Naval District was the first of four main administrative districts of the pre-war Imperial Japanese Navy. Its territory included Tokyo Bay and the Pacific Ocean, Pacific coasts of central and northern Honshū from the Kii Peninsula to Shimokita Peninsula. Its h ...

where she patrolled the entrance to

Tokyo Bay is a bay located in the southern Kantō region of Japan, and spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. Tokyo Bay is connected to the Pacific Ocean by the Uraga Channel. The Tokyo Bay region is both the most populous a ...

. On 23 April 1942, she was attached to the Port Moresby Operation (

Operation MO or the Port Moresby Operation was a Japanese plan to take control of the Australian Territory of New Guinea during World War II as well as other locations in the South Pacific. The goal was to isolate Australia and New Zealand from the Allied ...

) tasked with the occupation of the Australian

Territory of New Guinea The Territory of New Guinea was an Australian-administered United Nations trust territory on the island of New Guinea from 1914 until 1975. In 1949, the Territory and the Territory of Papua were established in an administrative union by the nam ...

in order to isolate

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

and

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 ...

from the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. The operation was also to seize the islands of

Tulagi Tulagi, less commonly known as Tulaghi, is a small island——in Solomon Islands, just off the south coast of Ngella Sule. The town of the same name on the island (pop. 1,750) was the capital of the British Solomon Islands Protectorate from 18 ...

and

Samarai Samarai is an island and former administrative capital in Milne Bay Province, Papua New Guinea. The island is historically significant as the site of a trading port and stop-over between Australia and East Asia. Samarai town was established on ...

, and the

Deboyne Islands The Deboyne Islands are an atoll, composed of a group of reefs and islands in the north of the Louisiade Archipelago, Papua New Guinea. Geography They are located from Misima and from the Torlesse Islands. Islands in the Deboyne Islands incl ...

(where seaplane bases were to be established) as well as

Nauru Nauru ( or ; na, Naoero), officially the Republic of Nauru ( na, Repubrikin Naoero) and formerly known as Pleasant Island, is an island country and microstate in Oceania, in the Central Pacific. Its nearest neighbour is Banaba Island in Ki ...

and

Banaba Island BanabaThe correct spelling and etymology in Gilbertese should be ''Bwanaba'' but the Constitution of Kiribati writes Banaba. Because of the spelling in English or French, the name was very often written Paanapa or Paanopa, as it was in 1901 Ac ...

(due to their valuable

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phospho ...

deposits). ''Wa-1'' was assigned to the Tulagi invasion force commanded by

Rear Admiral Rear admiral is a senior naval flag officer rank, equivalent to a major general and air vice marshal and above that of a commodore and captain, but below that of a vice admiral. It is regarded as a two star "admiral" rank. It is often regarde ...

Kiyohide Shima was an admiral in the Imperial Japanese Navy during World War II. Biography A native of Miyazaki prefecture, Shima was a graduate of the 39th class of the Imperial Japanese Naval Academy in 1911, ranking 69th out of 148 cadets. As a midshipman, h ...

and consisting of the flagship

minelayer A minelayer is any warship, submarine or military aircraft deploying explosive mines. Since World War I the term "minelayer" refers specifically to a naval ship used for deploying naval mines. "Mine planting" was the term for installing controll ...

cruiser A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several roles. The term "cruiser", which has been in use for several hu ...

, auxiliary minelayer ''Kōei Maru'', 2 destroyers ( and ), 5

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 ...

s (''Wa-1'' along with , ''Hagoromo Maru'', ''Noshiro Maru No. 2'', and ), 2 subchasers (''Toshi Maru No. 3'', ''Tama Maru No. 8''), and 1 transport () carrying 400 men of the 3rd Kure Special Naval Landing Force. The light carrier provided air support accompanied by 4 cruisers (, , , ) and 1 destroyer (). The force departed from Rabaul on 30 April 1942 and on 3 May 1942, landed on Tulagi unopposed. ''Shōhō'' with its escorts left the area to support the main Port Moresby operation leaving the task force without air cover. After completing their mine-sweeping activities at Tulagi, ''Wa-1'', ''Wa-2'' and ''Tama Maru'' were en route to the

when they were spotted by a squadron of

Douglas TBD Devastator The Douglas TBD Devastator was an American torpedo bomber of the United States Navy. Ordered in 1934, it first flew in 1935 and entered service in 1937. At that point, it was the most advanced aircraft flying for the Navy and possibly for any na ...

s from north of

Savo Island Savo Island is an island in Solomon Islands in the southwest South Pacific ocean. Administratively, Savo Island is a part of the Central Province of the Solomon Islands. It is about from the capital Honiara. The principal village is Alialia, ...

. ''Wa-1'' was hit by a 1,000-pound bomb and destroyed. ''Wa-2'' suffered the same fate while ''Tama Maru'' was significantly damaged and sank on 6 May 1942. She was struck from the Naval List on 10 July 1942.

References

Bibliography

* , History of Pacific War Vol.51 ''The truth histories of the Japanese Naval Vessels Part-2'',

Gakken is a Japanese publishing company founded in 1947 by Hideto Furuoka, which also produces educational toys. Their annual sales is reported at ¥ 90 billion ($789 million US). Gakken publishes educational books and magazines and produces other ...

(Japan), August 2005, . * Ships of the World special issue Vol.45, ''Escort Vessels of the Imperial Japanese Navy'', , (Japan), 1996. * The Maru Special, Japanese Naval Vessels No.50, ''Japanese minesweepers and landing ships'', (Japan), 1981. {{DEFAULTSORT:Wa-1 1942 ships No.1-class auxiliary minesweeper Ships built by Osaka Iron Works Maritime incidents in May 1942 World War II minesweepers of Japan Mine warfare vessels of the Imperial Japanese Navy Ships sunk by US aircraft