The submarines were medium-sized submarines of the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrend ...

(IJN), serving during the 1920s and

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

. The ''Type L'' submarines were built with

Vickers Vickers was a British engineering company that existed from 1828 until 1999. It was formed in Sheffield as a steel foundry by Edward Vickers and his father-in-law, and soon became famous for casting church bells. The company went public i ...

naval technical guidance. All boats were built in the

Mitsubishi Heavy Industries is a Japanese multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the predecessor of Mitsubishi Mo ...

-Kobe Shipyard by the contract with Vickers.

Class variants

The ''Type L'' submarines were divided into four classes: * * * *

''Type L1 (Ro-51-class)''

In 1916, the Mitsubishi Shipbuilding Corporation got the Vickers ''L'' class submarine informations. Mitsubishi which lost competition to the Kawasaki's ''Type F'' submarines ( Fiat- Laurenti design, ''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 six submarine kits, and built two 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 engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...

s and made many variants of similar design, for example:

Kampon 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 n ...

Mk.24 diesel for the '' ''Ro-100'' class. *Boats in class

''Type L2 (Ro-53-class)''

The ''Type L2'' had minor changes from the ''Type L1''. 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

''Type L3 (Ro-57-class)''

The ''Type L3'' is a license production model of the British ''L'' class submarine Group 2. *Boats in class

''Type L4 (Ro-60-class)''

The ''Type L4'' is a license production model of the British ''L'' class submarine Group 3. Their performance was good. The IJN was satisfied with them and stopped the development of ''Kaichū'' type submarines 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. *Boats in class

Characteristics

Bibliography

*'', History of Pacific War Extra, "Perfect guide, The submarines of the Imperial Japanese Forces"'', Gakken (Japan), March 2005, *''The Maru Special, Japanese Naval Vessels No.43 Japanese Submarines III'', Ushio Shobō (Japan), September 1980, Book code 68343-44 *''The Maru Special, Japanese Naval Vessels No.132 Japanese Submarines I "Revised edition"'', Ushio Shobō (Japan), February 1988, Book code 68344-36 *''The Maru Special, Japanese Naval Vessels No.133 Japanese Submarines II "Revised edition"'', Ushio Shobō (Japan), March 1988, Book code 68344-37

References

{{DEFAULTSORT:L0 type submarines L type submarine, Japan Submarines of the Imperial Japanese Navy