No.1 class auxiliary minesweeper

Class overview
Auxiliary Minesweeper No.1 in January 1942
Name:	No.1 class auxiliary minesweeper
Builders:	Hitachi Zōsen Corporation Namura Shipbuilding Corporation Naniwa Dock Company Ōsaka Iron Works Sanoyasu Dock Company
Operators:	Imperial Japanese Navy Soviet Navy Republic of China Navy People's Liberation Army Navy
Built:	1941–1943
In commission:	1942–1945 (IJN)
Planned:	22
Completed:	22
Lost:	7
Retired:	15
General characteristics
Type:	Minesweeper
Displacement:	215 long tons (218 t) standard
Length:	33.00 m (108 ft 3 in) overall
Beam:	5.92 m (19 ft 5 in)
Draught:	2.29 m (7 ft 6 in)
Propulsion:	1 × Akasaka Model diesel single shaft, 300 bhp
Speed:	9.5 knots (10.9 mph; 17.6 km/h)
Range:	1,500 nmi (2,800 km) at 9.5 kn (10.9 mph; 17.6 km/h)
Complement:	43
Armament:	• 1 × 76.2 mm (3.00 in) L/23.5 AA gun • 2 × 7.7 mm machine guns • 12 × depth charges • 1 × dunking hydrophone • 2 × paravanes

The No.1 class auxiliary minesweeper (第一号型掃海特務艇,, Dai Ichi Gō-gata Sōkai-Tokumutei^?) was a class of minesweepwes of the Imperial Japanese Navy (IJN), serving during World War II. 22 vessels were planned and built in 1941–43 under the Maru Rin Programme (Ship # 251–256) and the Maru Kyū Programme (Ship # 480–495).

1 Background
2 Ships in class
3 Photos
4 Notes
5 Bibliography

Background

In 1938, the IJN was troubled by drifting contact mines from the National Revolutionary Army at Yangtze River. The IJN dispatched a lot of minesweepers and paravane equipment vessels (minelayers, torpedo boats and more) to Yangtze River, but they were damaged by a drifting contact mines too.
The IJN wanted a small and light-footed minesweepers. The IJN already commandeered a lot of fishing boats and gave minesweeping operations to them. The Kampon designed minesweeper similar to the trawlers. It is No.1-class auxiliary minesweeper (Project Number I5).
They have begun to be commissioned from 1942. However, all of them was dispatched to Pacific front, and they were no match for the magnetic mine because their hull was made by steel.

Ships in class

Ship #	Ship	Builder	Laid down	Launched	Completed	Fate
251	Aux. Minesweeper No.1 ^[1]	Ōsaka Iron Works	30 June 1941	9 November 1941	31 January 1942	Sunk by air raid off Savo Island on 4 May 1942. Decommissioned on 25 May 1942.
252	Aux. Minesweeper No.2	Ōsaka Iron Works	30 June 1941	9 November 1941	28 February 1942	Sunk by air raid off Savo Island on 4 May 1942. Decommissioned on 25 May 1942.
253	Aux. Minesweeper No.3	Ōsaka Iron Works	20 June 1941	31 March 1942	30 May 1942	MIA on 24 July 1945.^[2] Decommissioned on 3 May 1947.
254	Aux. Minesweeper No.4	Naniwa Dock Company	20 June 1941	19 March 1942	29 June 1942	Sunk by air raid off Timor Island on 19 July 1944. Decommissioned on 10 September 1944.
255	Aux. Minesweeper No.5	Ōsaka Iron Works	20 June 1941	31 March 1942	30 June 1942	Survived war at Chuuk Islands. Decommissioned in 1947.^[3]
256	Aux. Minesweeper No.6	Naniwa Dock Company	20 February 1942	18 July 1942	30 October 1942	Sunk by air raid at Yamada Bay on 10 August 1945. Decommissioned on 20 October 1945.
480	Aux. Minesweeper No.7	Ōsaka Iron Works	10 February 1942	16 July 1942	28 December 1942	Survived war at Singapore. Surrendered to United Kingdom in July 1946.^[3] Decommissioned in 1947.^[3]
481	Aux. Minesweeper No.8	Ōsaka Iron Works	10 February 1942	16 July 1942	31 January 1943	Sunk by air raid at Visayan Sea on 21 October 1944. Decommissioned on 10 May 1945.
482	Aux. Minesweeper No.9	Namura Shipbuilding	20 March 1942	15 August 1942	30 November 1942	Survived war at Singapore. Surrendered to United Kingdom in July 1946.^[3] Decommissioned in 1947.^[3]
483	Aux. Minesweeper No.10	Sanoyasu Dock Company	3 March 1942	19 August 1942	30 November 1942	Sunk by USN destroyer off Vigan on 12 January 1945. Decommissioned on 10 May 1945.
484	Aux. Minesweeper No.11	Naniwa Dock Company	6 April 1942	30 August 1942	24 February 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to United Kingdom on 14 November 1947.
485	Aux. Minesweeper No.12	Naniwa Dock Company	7 September 1942	27 December 1942	31 March 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Soviet Union on 3 October 1947.
486	Aux. Minesweeper No.13	Hitachi Zōsen	21 July 1942	25 January 1943	14 April 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to United States on 1 October 1947. Sunk as target at on 12 February 1948.^[4]
487	Aux. Minesweeper No.14	Hitachi Zōsen	21 July 1942	25 January 1943	14 May 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Republic of China on 3 October 1947 and renamed Saolei 201. Escape to People's Liberation Army on 17 February 1949 and renamed Qiufeng. Decommissioned in 1976.
488	Aux. Minesweeper No.15	Namura Shipbuilding	29 August 1942	25 January 1943	30 April 1943	Survived war.^[5] Decommissioned on 30 November 1945.
489	Aux. Minesweeper No.16	Sanoyasu Dock Company	24 August 1942	19 December 1942	31 March 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to United Kingdom on 14 November 1947.
490	Aux. Minesweeper No.17	Naniwa Dock Company	7 September 1942	12 March 1943	28 May 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Soviet Union on 3 October 1947.
491	Aux. Minesweeper No.18	Namura Shipbuilding	15 February 1943	16 May 1943	31 July 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to United States on 3 October 1947. Sunk as target at on 21 January 1948.^[4]
492	Aux. Minesweeper No.19	Sanoyasu Dock Company	25 December 1942	25 March 1943	30 June 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Republic of China on 3 October 1947 and renamed Saolei 202. Renamed Jiangyong (YP-542) in 1952. Decommissioned in 1968. Scrapped.
493	Aux. Minesweeper No.20	Naniwa Dock Company	5 February 1943	27 April 1943	31 July 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Soviet Union on 3 October 1947.
494	Aux. Minesweeper No.21	Hitachi Zōsen	16 October 1942	11 March 1943	15 June 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to United States on 1 October 1947. Sunk as target at on 30 October 1947.^[4]
495	Aux. Minesweeper No.22	Namura Shipbuilding	20 May 1943	5 July 1943	20 October 1943	Survived war. Decommissioned on 30 November 1945. Surrendered to Republic of China on 3 October 1947 and renamed Saolei 203. Renamed Jiangyi (YP-541) in 1952. Decommissioned in 1968. Scrapped.

Photos

Notes

^ Auxiliary Minesweeper No.1 (第一号掃海特務艇, Dai 1 Gō Sōkai-Tokumutei^?). The same shall apply hereinafter.
^ One opinion: Sunk by USN carrier task force off Surabaya.
^ ^a ^b ^c ^d ^e Detailed date was unidentified.
^ ^a ^b ^c Disposition of U.S. Share of Japanese Naval Vessels, Report on. [File: CNFE/OS-15/L11-3]
^ Another opinion: Exploded and sunk by cause unknown at Jinhae on 14 August 1945.

Bibliography

"Rekishi Gunzō". http://rekigun.net/. , History of Pacific War Vol.51 The truth histories of the Japanese Naval Vessels Part-2, Gakken (Japan), August 2005, ISBN 4-05-604083-4
Ships of the World special issue Vol.45, Escort Vessels of the Imperial Japanese Navy, "Kaijinsha". http://www.ships-net.co.jp/. , (Japan), February 1996
The Maru Special, Japanese Naval Vessels No.50, Japanese minesweepers and landing ships, "Ushio Shobō". http://www.kojinsha.co.jp/. (Japan), April 1981

Japanese auxiliary ship classes of World War II

Colliers and Oilers	Notoro · Ondo · Sunosaki · Ashizuri · Kazahaya ^S · Hayasui ^S · Hario ^S · Muroto · Ōse (ex-Dutch tanker Genota) ^SC

Food supply ships	Mamiya ^S · Nosaki ^S · Kinesaki · Irako ^S · Kurasaki ^SC

Landing ships	No.1 · No.101 · Shinshū Maru ^S (Army) · SS (Army)

Minelayers and Cable layer	Tokiwa ^SC · Itsukushima ^S · Yaeyama ^S · Okinoshima ^S · Tsugaru ^S · Minoo ^SC · Shirataka ^S · Hatsutaka · Tsubame · Natsushima (1933) · Sokuten (1938) · Hirashima · Ajiro ^S · Kamishima · Hashima · Sokuten (1913) · Aux. No.1 · Aux. No.101 (ex-HMS Barlight) ^SC

Minesweepers	No.1 (1923) · No.5 (1928) · No.13 · No.17 · No.7 (1938) · No.19 · No.101 (ex-HMS Taitam and Waglan) ^C · Aux. No.1 · Aux. No.101 (ex-HNLMS DEFG class) · Aux. No.104 (ex-HNLMS DEFG class)

Patrol boats	No.1 ^C · No.31 ^C · No.46 ^SC · No.101 (ex-HMS Thracian) ^SC · No.102 (ex-USS Stewart) ^SC · No.103 (ex-USS Finch) ^SC · No.104 (ex-Dutch East Indies Valk and Arend) ^C · No.105 (ex-Philippine customs Arayat) ^SC · No.106 (ex-HNLMS Banckert) ^SCI · No.107 (ex-USS Genesee) ^SC · No.109 (ex-Dutch East Indies Fazant) ^SC · Aux. No.1

Repair ships	Asahi ^SC · Akashi ^S · Hayase (ex-Chinese passenger Chin Kiang)^SC · Hitonose (ex-ROCN Min Sheng)^SC

Seaplane tenders	Notoro ^SC · Kamoi ^SC · Chitose · Mizuho ^S · Nisshin ^S · Akitsushima ^S

Submarine chasers	No.1 · No.3 ^S · No.4 · No.13 · No.28 · No.60 · Aux. No.1 · Aux. No.101 (ex-HNLMS Tjerimai) ^SC · Aux. No.102 (ex-HNLMS Ardjoeno class) ^C · Aux. No.103 (ex-HNLMS B1 class) ^C · Aux. No.111 (ex-HNLMS P13 or P14) ^SC · Aux. No.112 (ex-HNLMS A class) ^C · Aux. No.117 (ex-HNLMS Bantam) ^C · Aux. No.251 · Aux. No.253 ^S

Submarine tenders	Komahashi ^SC · Jingei · Taigei ^S

Survey ships	Tsukushi ^S · Katsuriki ^SC · Hakusa (ex-China customs Fu Hsing)^SC

Target ships	Settsu ^SC · Yakaze ^SC · Hakachi ^S · Ōhama ^S

Training ships	Fuji ^SC · Shikishima ^SC · Asama ^SC · Azuma ^SC · Kasuga ^SC · Atada (ex-ROCN Yat Sen) ^SC

Others	Sōya (freighter)^SC · Kashino (turret transporter)^S · Ōtomari (icebreaker)^S · Tategami (salvage tug) · Kasashima (salvage tug) · Miura (salvage tug) · Kaiyō No.1 (oceanographic research ship) · Asuka (traffic ship, ex-ROCN Yung Chien) ^SC

^S - Single ship of class • ^C - Converted to ship type • ^I - Incomplete until the end of war