W-7-class minesweeper (1938)

No.7 on 23 September 1942
Class overview
Name:	No.7-class minesweeper
Builders:	Maizuru Naval Arsenal Tama Shipyard Tōkyō Ishikawajima Shipyard Uraga Dock Company
Operators:	Imperial Japanese Navy
Preceded by:	No.13 class
Succeeded by:	No.19 class
Cost:	2,230,823 JPY (in 1937)
Built:	1937 – 1939
In commission:	1938 – 1946
Planned:	6
Completed:	6
Lost:	5
Retired:	1
General characteristics
Displacement:	630 long tons (640 t) standard
Length:	72.50 m (237 ft 10 in) overall
Beam:	7.85 m (25 ft 9 in)
Draught:	2.60 m (8 ft 6 in)
Propulsion:	2 × triple expansion stages reciprocating engines 2 × Kampon mix-fired boilers 2 shafts, 3,850 shp
Speed:	20.0 knots (23.0 mph; 37.0 km/h)
Range:	2,000 nmi (3,700 km) at 14 kn (16 mph; 26 km/h)
Complement:	98
Armament:	3 × 120 mm (4.7 in) L/45 naval guns 2 × 25 mm AA guns 36 × depth charges 1 × Type 94 depth charge projector 6 × paravanes

The No.7-class minesweepers (第七号型掃海艇, Dai Nana Gō-gata Sōkaitei) were a class of minesweepers of the Imperial Japanese Navy (IJN), serving during the Second Sino-Japanese War and World War II. 6 vessels were built in 1937-39 under the Maru 3 Keikaku.

Background

• Project number I4. Improved model of the No.13-class. They were built to update timeworn No.7 class, No.9 class and No.11 class.^[1] Kampon deleted minelayer facility from them, because IJN hoped they act in Yangtze River. And they added to 1 × 120 mm naval gun for engage with National Revolutionary Army. Therefore, No.7 class had the silhouette which resembled torpedo boat Chidori class and Ōtori class as well.

Ships in class

Ship #	Ship	Builder	Laid down	Launched	Completed	Fate
49	No. 7 [2]	Tama Shipyard	27 October 1937	16 June 1938	15 December 1938	Sunk by HMS Storm off Port Blair on 15 April 1944. Decommissioned on 10 June 1944.
50	No. 8	Uraga Dock Company	11 December 1937	28 May 1938	15 February 1939	Scuttled by Royal Navy at Singapore on 10 July 1946. Decommissioned on 10 August 1946.
51	No. 9	Maizuru Naval Arsenal	7 February 1938	10 September 1938	15 February 1939	Struck a naval mine and sunk at Ambon on 1 February 1942. Decommissioned on 10 April 1942.
52	No. 10	Tōkyō Ishikawajima Shipyard	21 December 1937	22 September 1938	15 February 1939	Sunk by air raid off Vigan on 10 December 1941. Decommissioned on 15 March 1942.
53	No. 11	Uraga Dock Company	30 May 1938	28 December 1938	15 July 1939	Sunk by air raid off Makassar on 28 March 1945. Decommissioned on 10 May 1945.
54	No. 12	Tōkyō Ishikawajima Shipyard	28 May 1938	18 February 1939	15 August 1939	Sunk by USS Besugo off Flores 08°13′S 119°14′E / 8.217°S 119.233°E on 6 April 1945. Decommissioned on 25 May 1945.

Footnotes

1. No.7 (ex.-Umikaze), No.8 (ex.-Yamazkaze), No.9 (ex.-Nara), No.10 (ex.-Enoki), No.11 (ex.-Nagatsuki) and No. 12 (ex.-Kikutsuki)
2. Minesweeper No. 7 (第七号掃海艇 Dai 7 Gō Sōkaitei). The same shall apply hereinafter.

Bibliography

• Ships of the World special issue Vol.45, Escort Vessels of the Imperial Japanese Navy, "Kaijinsha"., (Japan), February 1996
• The Maru Special, Japanese Naval Vessels No.50, Japanese minesweepers and landing ships, "Ushio Shobō". (Japan), April 1981