Ashi
Class overview
Name	Momi class
Builders	Kawasaki Dockyard Co. (6) Tōkyō Ishikawajima Shipyard (4) Uraga Dock Company (4) Fujinagata Shipyards (3) Kure Naval Arsenal (2) Yokosuka Naval Arsenal (2)
Operators	Imperial Japanese Navy
Preceded by	Kawakaze class
Succeeded by	Minekaze class
Built	1918–1923
In commission	1919–1946
Planned	28
Completed	21
Cancelled	7
Lost	11
Scrapped	10
General characteristics as built
Type	Destroyer
Displacement	864 t (850 long tons) (normal) 1,036 t (1,020 long tons) (deep load)
Length	83.8 m (275 ft) (pp) 85.3 m (280 ft) (o/a)
Beam	7.9 m (26 ft)
Draft	2.4 m (8 ft)
Installed power	21,500 shp (16,000 kW) 3 × Kamponwater-tube boilers
Propulsion	2 shafts; 2 ×Parsonssteam turbines
Speed	36knots (67 km/h; 41 mph)
Range	3,000 nmi (5,600 km; 3,500 mi) at 15 knots (28 km/h; 17 mph)
Complement	148
Armament	3 × single12 cm (4.7 in) Type 3 guns 2 × twin 53.3 cm (21.0 in)torpedo tubes

TheMomi-class destroyers were a class of twenty-one second-classdestroyers of theImperial Japanese Navy.^[1] All were named for plants. Obsolete by the beginning of thePacific War, theMomis were relegated to mostly secondary roles, with some vessels serving throughout the war as patrol vessels or high speed transports.

Construction of the medium-sizedMomi-class destroyers was authorized as part of the Imperial Japanese Navy's8-4 Fleet Program from fiscal 1918–1920, as an accompaniment to the largerMinekaze class with which they shared many common design characteristics.^[2] These vessels were produced at several shipyards around Japan, and when formed into attack squadrons of two to four vessels, made up the backbone of the inter-war Imperial Japanese Navy.^[3]

The final seven vessels planned for this series were cancelled, and re-ordered as the newWakatake-class destroyers in 1919, and by the mid-1920s the concept of the "second-class destroyer" had fallen out of favor due to the greater capabilities offered by the new generation of fleet destroyers.^[4]

TheMomi class was a development of theEnoki second-class destroyers, relying on the same basichull. They were quite small, comparable toRoyal Navycorvettes. The design incorporated features discovered onGerman destroyers awarded as reparations fromWorld War I, including a lengthenedforecastle with a break forming awell deck immediately forward of thebridge, and a front gun battery placed on a pedestal on the centerline so that it could be operated in heavy weather. This arrangement also offered the advantage of a low, semi protected area for the forward torpedo tubes albeit at the cost of becoming awash in heavy seas.^[5] Initial problems with stability during high-speed turns were later corrected by widening the beam and bringing up the waterline.

When compared with theMinekaze class, the smaller size necessitated a reduction from fourboilers to three and the adoption of lighter-weightParsons direct-driveturbines, resulting in a drop from 38,500 hp in theMinekaze class to 21,500 hp (16,000 kW) in theMomi class. In addition, fuel capacity was lowered to 275 tons of oil fuel.

As gear turbine technology was not yet perfected, the navy experimented with a variety of power plants on theMomi class:

TheMomi class was heavily armed for its small displacement, with amain battery ofType 3 120 mm 45 caliber naval guns, the same as was used on theMinekaze-class, and a set of doubletorpedo launchers. Anti-aircraft protection was provided by two 7.7mm machine guns.^[4]

Due to their shallow draft, theMomi-class destroyers proved to be excellent for operation in coastal waters, and were used along the coast ofChina to support amphibious landings during theSecond Sino-Japanese War.

A number of theMomi-class vessels were lost or disposed during the interwar period.Momi herself was turned over to trials in 1932, whileWarabi was run down by the cruiserJintsu on 27 August 1927 offMaizuru, Kyoto.Kaya andNashi were scrapped in 1939.^[4]

Also in 1939,Aoi,Fuji,Hagi,Hishi,Kiku,Satsuki,Tade,Tsuta andYomogi were removed from front line combat service and converted into patrol vessels. In 1940,Ashi,Kaki,Nine,Sumire, andTake were disarmed, and re-rated as training ships.^[4]

By the time of thePacific War, theMomi-class was reaching the end of its service life, and only three (Tsuga,Hasu andKuri) remained in service as destroyers. An effort was made to upgrade their capabilities by removing the minesweeping gear from the stern and replacing with 36 to 48depth charges and four depth charge launchers. The amidships Type 3 guns was replaced by two tripleType 96 AA guns from 1942 to 1943, and a Type 13 radar was added.Tsuga was sunk by air attack 15 January 1945.Hasu was surrendered and scrapped at the end of the war.Kuri was surrendered, but sank after striking amine offKorea on 8 October 1945.^[4]

Beginning in 1939, nineMomi-class vessels were re-classified as patrol boats and converted for escort duty, having one boiler removed (dropping their power to 12,000 ihp (8,900 kW) and speed to just 18knots (21 mph; 33 km/h). Their torpedo tubes, minesweeping gear, and the amidships Type 3 gun mount were replaced by sixType 96 25 mm AT/AA Guns, 36depth charges, and three depth charge throwers.^[4] As well, their names were dropped and they were simply numbered.

During 1941–1942, these vessels were modified again, to carry and launch aToku Daihatsu-class landing craft, by having the aft smokestack removed and the stern modified with a sloping deck to the waterline, as well as providing accommodation for 150naval infantry troops. All of these vessels except ex-Fuji (asPatrol Boat #36) were sunk during the course of thePacific War.^[4]

Wikimedia Commons has media related toMomi class destroyer.

• Gardiner, Robert & Gray, Randal, eds. (1985).Conway's All the World's Fighting Ships 1906–1921. Annapolis, Maryland: Naval Institute Press.ISBN 0-85177-245-5.
• Evans, David (1979).Kaigun: Strategy, Tactics, and Technology in the Imperial Japanese Navy, 1887-1941. US Naval Institute Press.ISBN 0-87021-192-7.
• Howarth, Stephen (1983).The Fighting Ships of the Rising Sun: The Drama of the Imperial Japanese Navy, 1895–1945. Atheneum.ISBN 0-689-11402-8.
• Jentschura, Hansgeorg; Jung, Dieter & Mickel, Peter (1977).Warships of the Imperial Japanese Navy, 1869–1945. Annapolis, Maryland: United States Naval Institute.ISBN 0-87021-893-X.
• Watts, Anthony J. & Gordon, Brian G. (1971).The Imperial Japanese Navy. Garden City, New York: Doubleday.ISBN 0385012683.

• Destroyer classes
• Momi-class destroyers
• World War II destroyers of Japan

• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from August 2021
• Articles containing Japanese-language text
• Commons category link is on Wikidata