Momi-class destroyer


The Momi-class destroyers were a class of twenty-one second-class destroyers of the Imperial Japanese Navy. All were named for plants. Obsolete by the beginning of the Pacific War, the Momis were relegated to mostly secondary roles, with some vessels serving throughout the war as patrol vessels or high speed transports.

Background

Construction of the medium-sized Momi-class destroyers was authorized as part of the Imperial Japanese Navy's 8-4 Fleet Program from fiscal 1918-1920, as an accompaniment to the larger with which they shared many common design characteristics. 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.
The final seven vessels planned for this series were cancelled, and re-ordered as the new s 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.

Initial design

The Momi class was a development of the second-class destroyers, relying on the same basic hull. They were quite small, comparable to Royal Navy corvettes. The design incorporated features discovered on German destroyers awarded as reparations from World War I, including a lengthened forecastle with a break forming a well deck immediately forward of the bridge, 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. Initial problems with stability during high-speed turns were later corrected by widening the beam and bringing up the waterline.
When compared with the Minekaze class, the smaller size necessitated a reduction from four boilers to three and the adoption of lighter-weight Parsons direct-drive turbines, resulting in a drop from 38,500 hp in the Minekaze class to in the Momi 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 the Momi class:
TurbinesEquipment for
Brown-Curtis turbinesKaya, Warabi and Tade
Parsons impulse turbinesHishi and Hasu
Escher Wyss & Cie Zoelly turbinesSumire
Mitsubishi Shipbuilding High-pressure
impulse turbine and low-pressure reaction turbine		Kaki
Kampon turbinesall others

The Momi class was heavily armed for its small displacement, with a main battery of Type 3 120 mm 45 caliber naval guns, the same as was used on the Minekaze-class, and a set of double torpedo launchers. Anti-aircraft protection was provided by two 7.7mm machine guns.

Early operational history

Due to their shallow draft, the Momi-class destroyers proved to be excellent for operation in coastal waters, and were used along the coast of China to support amphibious landings during the Second Sino-Japanese War.
A number of the Momi-class vessels were lost or disposed during the interwar period. Momi herself was turned over to trials in 1932, while Warabi was run down by the cruiser on 27 August 1927 off Maizuru, Kyoto. Kaya and Nashi were scrapped in 1939.
Also in 1939, Aoi, Fuji, Hagi, Hishi, Kiku, Satsuki, Tade, Tsuta and Yomogi were removed from front line combat service and converted into patrol vessels. In 1940, Ashi, Kaki, Nine, Sumire, and Take were disarmed, and re-rated as training ships.
By the time of the Pacific War, the Momi-class was reaching the end of its service life, and only three 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 48 depth charges and four depth charge launchers. The amidships Type 3 guns was replaced by two triple Type 96 AA guns from 1942–1943, 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 a mine off Korea on 8 October 1945.

As patrol boats

Beginning in 1939, nine Momi-class vessels were re-classified as patrol boats and converted for escort duty, having one boiler removed were sunk during the course of the Pacific War.

List of ships

KanjiNameBuilderLaid downLaunchedCompletedFate
樅Yokosuka Naval Arsenal, Japan23 January 191810 June 191927 December 1919Decommissioned 1 April 1932; renamed Disposal Destroyer No.2; used for trials to 1936.
榧Yokosuka Naval Arsenal, Japan23 December 191810 June 191928 March 1920Decommissioned 1 February 1940 and scrapped.
梨Kawasaki Shipyards, Kobe, Japan2 February 191826 August 191910 December 1919Decommissioned 1 February 1940 and scrapped.
竹Kawasaki Shipyards, Kobe, Japan2 December 191826 August 191925 December 1919Decommissioned 1 February 1940; converted to training ship; scuttled as breakwater at Akita port in 1948.
柿Uraga Dock Company, Japan27 February 191920 October 19192 August 1920Decommissioned 1 April 1940; converted to training ship; re-converted to auxiliary ship Ōsu 23 February 1945; scrapped 1948.
栂Ishikawajima Shipyards, Japan5 March 191917 April 192020 June 1920Sunk off Taiwan 15 January 1945 in air attack; struck 10 March 1945.
楡Kure Naval Arsenal, Japan5 September 191922 December 191931 March 1920Decommissioned 1 February 1940; converted to training ship, re-converted to auxiliary ship No.1 Tomariura 15 December 1944; scrapped 1948.
栗Kure Naval Arsenal, Japan5 December 191919 March 192030 April 1920Mined off Pusan 8 October 1945; struck 25 October 1945.
菊Kawasaki Shipyards, Kobe, Japan20 January 192013 October 192010 December 1920Converted to Patrol Boat No.31 1 April 1940; sunk at Palau 30 March 1944 by air attack; struck 10 May 1944.
葵Kawasaki Shipyards, Kobe, Japan1 April 19209 November 192010 December 1920Converted to Patrol Boat No.32 1 April 1940; grounded 23 December 1941 at Wake Island ; struck 15 January 1942.
萩Uraga Dock Company, Japan28 February 192029 October 192020 April 1921Converted to Patrol Boat No.33 1 April 1940; grounded 23 December 1941 at Wake Island ; struck 15 January 1942.
藤Fujinagata Shipyards, Japan6 December 191927 November 192031 May 1921Converted to Patrol Boat No.36 1 April 1940; surrendered to Netherlands on July 1946 at Surabaya; scrapped 10 August 1946.
薄Ishikawajima Shipyards, Japan3 May 192021 February 192125 May 1921Converted to Patrol Boat No.34 1 April 1940; sunk 6 March 1943 in collision with off Kavien; written off 10 January 1945.
菱Uraga Dock Company, Japan10 November 19209 May 192123 March 1922Converted to Patrol Boat No.37 1 April 1940; sunk off Borneo by 24 January 1942; struck 10 April 1942.
蓮Uraga Dock Company, Japan2 March 19218 December 192131 July 1922Retired 12 October 1945; scuttled as breakwater in Fukui, 1946.
蕨Fujinagata Shipyards, Japan12 October 192028 September 192119 December 1921Sunk 24 August 1927 in collision with off Cape Miho; struck 15 September 1927.
蓼Fujinagata Shipyards, Japan20 December 192015 March 192131 July 1922Converted to Patrol Boat No.39 1 April 1940; torpedoed S of Yonaguni by 23 April 1943; struck 1 July 1943.
菫Ishikawajima Shipyards, Japan24 November 192014 December 192131 March 1923Decommissioned 1 February 1940; converted to training ship, re-converted to auxiliary ship Mitaka 23 February 1945; scrapped 1948.
蔦Kawasaki Shipyards, Kobe, Japan16 October 19209 May 192130 June 1921Converted to Patrol Boat No.35 1 April 1940; sunk at Lae by air attack 2 September 1942; struck 10 February 1943.
葦Kawasaki Shipyards, Kobe, Japan15 November 19203 September 192129 October 1921Decommissioned 1 February 1940; converted to training ship, re-converted to auxiliary ship No.2 Tomariura 15 December 1944; modified to Shin'yō suicide motorboatt mothership 1945, scrapped 1947.
蓬Ishikawajima Shipyards, Japan26 February 192114 March 192219 August 1922Converted to Patrol Boat No.38 1 April 1940: torpedoed Bashi Strait by 25 November 1944; struck 10 March 1945.