The submarines were medium sized submarines of the Imperial Japanese Navy

Imperial Japanese Navy

The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...

 (IJN), serving during the 1920s and the World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

. The L type submarines were built by Vickers

Vickers Limited

Vickers Limited was a famous British engineering conglomerate that merged into Vickers-Armstrongs in 1927.-Early history:Vickers was formed in Sheffield as a steel foundry by the miller Edward Vickers and his father-in-law George Naylor in 1828. Naylor was a partner in the foundry Naylor &...

 naval technical guidance. All boats were built in the Mitsubishi Heavy Industries

Mitsubishi Heavy Industries

, or MHI, is a Japanese company. It is one of the core companies of Mitsubishi Group.-History:In 1870 Yataro Iwasaki, the founder of Mitsubishi took a lease of Government-owned Nagasaki Shipyard. He named it Nagasaki Shipyard & Machinery Works, and started the shipbuilding business on a full scale...

-Kobe Shipyard by the contract with Vickers.

L1 type (Ro-51 class)

In 1916, the Mitsubishi Shipbuilding Corporation

Mitsubishi Heavy Industries

, or MHI, is a Japanese company. It is one of the core companies of Mitsubishi Group.-History:In 1870 Yataro Iwasaki, the founder of Mitsubishi took a lease of Government-owned Nagasaki Shipyard. He named it Nagasaki Shipyard & Machinery Works, and started the shipbuilding business on a full scale...

 got the Vickers L class submarine

British L class submarine

The British L class submarine were originally planned under the emergency war programme as an improved version of the British E class submarine. The scale of change allowed the L class to become a separate class....

 informations. Mitsubishi which lost competition to the Kawasaki

Kawasaki Shipbuilding Corporation

-External links:*...

's F type submarines (Fiat

Fiat

FIAT, an acronym for Fabbrica Italiana Automobili Torino , is an Italian automobile manufacturer, engine manufacturer, financial, and industrial group based in Turin in the Italian region of Piedmont. Fiat was founded in 1899 by a group of investors including Giovanni Agnelli...

-Laurenti type, Ro-1 class and Ro-3 class), bought the license for the L class submarine from Vickers. The IJN hoped an improvement of submarine technologies will be achieved and ordered this submarine from Mitsubishi. Mitsubishi bought 6 submarine kits, and built 2 boats by semi-knock down. The submarine crews were satisfied with the Vickers diesels because they proved to be reliable. The IJN studied the diesel engines and made many variants of similar design, for example: Kampon

Imperial Japanese Navy Technical Department

The was the externally operating division of the Ministry of the Navy of Japan responsible for the administration of naval vessel construction. From 1923 onward, it took on the role of a research institution for the research and development of naval technologies and engineering...

 Mk.24 diesel for the Ro-100 class

Ro-100 class submarine

The was a medium size submarine of the Imperial Japanese Navy , serving during World War II. The IJN official designation for this class was or .-Construction:...

.

• Boats in class

  Boat	Laid down	Launched	Completed	Fate
  No.25 Submarine the same shall apply hereinafter	10-08-1918	10-10-1919	30-06-1920	Renamed Ro-51 01-11-1924. Decommissioned 01-04-1940.
  No.26 Submarine Ro-52	10-08-1918	09-03-1920	30-11-1920	Renamed Ro-52 01-11-1924. Decommissioned 01-04-1932.

L2 type (Ro-53 class)

The L2 type had minor changes from the L1 type. The changes were:

• The ship's side torpedo tubes were removed.
• Changed the batteries. (The L1 was equipped 3 groups, 336 small-sized batteries. The L2 was equipped 2 groups, 224 medium-sized batteries.)

• Boats in class

  Boat	Laid down	Launched	Completed	Fate
  No.27 Submarine Ro-53	01-04-1919	06-07-1919	10-03-1921	Renamed Ro-53 01-11-1924. Decommissioned 01-04-1940.
  No.28 Submarine Ro-54	01-11-1919	13-11-1920	10-09-1921	Renamed Ro-54 01-11-1924. Decommissioned 01-04-1940.
  No.29 Submarine Ro-55	30-03-1920	10-02-1921	15-11-1921	Renamed Ro-55 01-11-1924. Decommissioned 01-04-1940.
  No.30 Submarine Ro-56	10-07-1920	11-05-1921	16-01-1922	Renamed Ro-56 01-11-1924. Decommissioned 01-04-1940.

L3 type (Ro-57 class)

The L3 type is a license production model of the British L class submarine Group 2

HMS L9

HMS L9 was a British L class submarine built by William Denny and Brothers, Dumbarton. She was laid down on in October 1916 and was commissioned on 27 May 1918....

.

• Boats in class

  Boat	Laid down	Launched	Completed	Results	Fate
  No.46 Submarine Ro-57	20-11-1920	03-12-1921	30-07-1922		Renamed Ro-57 01-11-1924. Decommissioned 20-11-1945. Later scuttled off Kure Kure, Hiroshima is a city in Hiroshima prefecture, Japan.As of October 1, 2010, the city has an estimated population of 240,820 and a population density of 681 persons per km². The total area is 353.74 km².- History :... .
  No.47 Submarine Ro-58	15-02-1921	02-03-1922	25-11-1922		Renamed Ro-58 01-11-1924. Decommissioned 15-09-1945. Later scuttled off Shimizu Shizuoka, Shizuoka is the capital city of Shizuoka Prefecture, Japan, and the prefecture's second-largest city in terms of both population and area. It became one of Japan's 19 "designated cities" in 2005.-Geography:... .
  No.57 Submarine Ro-59	18-05-1921	28-06-1922	20-03-1923		Renamed Ro-59 01-11-1924. Decommissioned 20-11-1945. Scuttled at Iyo Nada, May 1946.

L4 type (Ro-60 class)

The L4 type is a license production model of the British L class submarine Group 3

HMS L52

HMS L52 was a British L class submarine built by Armstrong Whitworth, Newcastle-Upon-Tyne. She was laid down on 16 May 1917 and was commissioned on an unknown date....

. Their performance was good. The IJN was satisfied with them and stopped the development of Kaichū type submarine

Kaichu type submarine

The submarines were double-hulled medium sized submarines of the Imperial Japanese Navy during World War II. They were derived from the .Several variants existed. From 1934 to 1944, the K6 type and the K7 type were built...

s for a long time. Later the IJN was not able to regain the technical delay in development of the medium-sized submarines until the end of the Pacific War

Pacific War

The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...

.

• Boats in class

  Boat	Laid down	Launched	Completed	Results	Fate
  No.59 Submarine Ro-60	05-12-1921	20-12-1922	17-09-1923		Renamed Ro-60 01-11-1924. Lost in an accident at Kwajalein Kwajalein Kwajalein Atoll , is part of the Republic of the Marshall Islands . The southernmost and largest island in the atoll is named Kwajalein Island. English-speaking residents of the U.S...  29-12-1941.
  No.72 Submarine Ro-61	05-06-1922	19-05-1923	09-02-1924	Sank USS Casco USS Casco (AVP-12) The third USS Casco was a United States Navy Barnegat-class small seaplane tender in commissioned from 1943 to 1947.-Construction and commissioning:...  30-08-1942	Renamed Ro-61 01-11-1924. Sunk by USS Reid USS Reid (DD-369) The third USS Reid was a in the United States Navy during World War II. She was named for Samuel Chester Reid.-History:Reid was laid down 25 June 1934 by Federal Shipbuilding and Drydock Company, Kearny, New Jersey; launched 11 January 1936; sponsored by Mrs. Beatrice Reid Power; and commissioned...  31-08-1942.
  No.73 Submarine Ro-62	08-09-1922	29-09-1923	24-07-1924		Renamed Ro-62 01-11-1924. Decommissioned 20-11-1945. Scuttled at Iyo Nada, May 1946.
  Ro-63	02-04-1923	24-01-1924	20-12-1924		Decommissioned 20-11-1945. Scuttled at Iyo Nada, May 1946.
  Ro-64	15-10-1923	19-08-1924	30-04-1925		Sunk by naval mine at Hiroshima Bay Hiroshima Bay is a bay in the Inland Sea, Japan. Administratively, the bay is divided between Hiroshima and Yamaguchi Prefectures. The bay's shore is a Ria. Its surface area is about 1,000 km², with a mean depth of 25 meters.-Municipalities:*Kure, Hiroshima...  12-04-1945.
  Ro-65	15-11-1924	19-09-1925	30-06-1926		Lost in an accident at Kiska Kiska Kiska is an island in the Rat Islands group of the Aleutian Islands of Alaska located at . It is about long and varies in width from - Discovery :...  04-11-1942.
  Ro-66	01-12-1925	25-10-1926	28-07-1927		Clashed with Ro-62 and sunk at southwest of Wake Island Wake Island Wake Island is a coral atoll having a coastline of in the North Pacific Ocean, located about two-thirds of the way from Honolulu west to Guam east. It is an unorganized, unincorporated territory of the United States, administered by the Office of Insular Affairs, U.S. Department of the Interior...  17-12-1941.
  Ro-67	05-03-1925	18-03-1926	15-12-1926		Decommissioned 20-07-1945. Scuttled off Sasebo Sasebo, Nagasaki is a city located in Nagasaki Prefecture, Japan. As of 2011, the city has an estimated population of 259,800 and the density of 609 persons per km². The total area is 426.47 km². The locality is famed for its scenic beauty. The city includes a part of Saikai National Park... , July 1948.
  Ro-68	06-02-1924	23-02-1925	29-10-1925		Decommissioned 30-11-1945. Scuttled off Maizuru Maizuru, Kyoto is a city located in Kyōto, Japan, on an inlet of the Sea of Japan.As of 2008, the city has an estimated population of 89,626 and the density of 264 persons per km². The total area is .The city was founded on May 27, 1943.... , 30-04-1946.

Characteristics

Type		L1 (Ro-51)	L2 (Ro-53)	L3 (Ro-57)	L4 (Ro-60)
Displacement	Surfaced	893 long tons (907 t)	893 long tons (907 t)	889 long tons (903 t)	988 long tons (1,004 t)
	Submerged	1075.2 long tons (1,092 t)	1075.3 long tons (1,093 t)	1102.7 long tons (1,120 t)	1301 long tons (1,322 t)
Length (overall)		70.59 metre	70.59 metre	72.89 metre	78.39 metre
Beam		7.16 metre	7.16 metre	7.16 metre	7.41 metre
Draft		3.9 metre	3.94 metre	3.96 metre	3.96 metre
Power plant and shaft		2 × Vickers diesels, 2 shafts	2 × Vickers diesels, 2 shafts	2 × Vickers diesels, 2 shafts	2 × Vickers diesels, 2 shafts
Power	Surfaced	2,400 bhp	2,400 bhp	2,400 bhp	2,400 bhp
	Submerged	1,600 shp	1,600 shp	1,600 shp	1,600 shp
Speed	Surfaced	17 knots (33.3 km/h)	17.3 knots (33.9 km/h)	17.1 knots (33.5 km/h)	15.7 knots (30.8 km/h)
	Submerged	10.2 knots (20 km/h)	10.4 knots (20.4 km/h)	9.1 knots (17.8 km/h)	8.6 knots (16.9 km/h)
Range	Surfaced	5500 nmi (10,186 km) at 10 knots (19.6 km/h)	5500 nmi (10,186 km) at 10 knots (19.6 km/h)	5500 nmi (10,186 km) at 10 knots (19.6 km/h)	5500 nmi (10,186 km) at 10 knots (19.6 km/h)
	Submerged	80 nmi (148.2 km) at 4 knots (7.8 km/h)	80 nmi (148.2 km) at 4 knots (7.8 km/h)	80 nmi (148.2 km) at 4 knots (7.8 km/h)	80 nmi (148.2 km) at 4 knots (7.8 km/h)
Test depth		60 m (196.9 ft)	60 m (196.9 ft)	60 m (196.9 ft)	60 m (196.9 ft)
Fuel		75 tons	75 tons	75 tons	75 tons
Complement		45	45	46	48
Armament (initial)		• 6 × 450 mm (18 in) TT Torpedo tube A torpedo tube is a device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units installed aboard surface vessels... s (4 × front, 2 × side) • 10 × Type 44 torpedoes • 1 × 76.2 mm (3 in) L/23.5 AA gun	• 4 × 450 mm TTs (4 × front) • 8 × Type 44 torpedoes • 1 × 76.2 mm L/23.5 AA gun	• 4 × 533 mm (21 in) TTs (4 × front) • 8 × 6th Year Type torpedoes • 1 × 76.2 mm L/23.5 AA gun • 1 × 6.5 mm machine gun	• 6 × 533 mm TTs (6 × front) • 12 × 6th Year Type torpedoes • 1 × 76.2 mm L/23.5 AA gun L/40 naval gun • 1 × 6.5 mm machine gun