The Cruiser submarine Type-B (巡潜乙型潜水艦, Junsen Otsu-gata sensuikan) was a class of submarine in the Imperial Japanese Navy (IJN) which served during World War II. The Type-B submarines were similar to the Type-A apart from not having the headquarters installation.
Class variants
The Type-B submarines were divided into four classes:
- Type-B (乙型（伊十五型）, Otsu-gata, I-15-class)
- Type-B Mod.1 (乙型改一（伊四十型）, Otsu-gata Kai-1, I-40-class)
- Type-B Mod.2 (乙型改二（伊五十四型）, Otsu-gata Kai-2, I-54-class)
- V22A Type (第5115号艦型, Dai-5115-Gō kan-gata, 5115th vessel-class). The 5115th vessel-class submarines were not built and remained a design only.
Type-B (I-15 class)
Project number S37. Twenty boats were built between 1937 and 1944 under the Maru 3 Programme (Boats 37 - 42) and Maru 4 Programme (Boats 139 - 152).
Type-B Mod.1 (I-40 class)
Project number S37B. Six boats were planned under the Maru Kyū Programme (Boats 370 - 375), all boats were completed. On the outside this class looked the same as the I-15 class; however, they were built from high-tensile strength steel and equipped with diesel engines of a simpler design.
Type-B Mod.2 (I-54 class)
Project number S37C. Twenty-one boats were planned under the Maru Kyū Programme (Boats 627 - 636) and Kai-Maru 5 Programme (Boats 5101 - 5114). Eighteen boats were cancelled in late 1943, because the IJN was setting the Type E submarine (戊型潜水艦, Bo-gata sensuikan) as 1945's main submarines.
- Boats in class
V22A Type
Project number S49A. Eighteen boats were planned under the Kai-Maru 5 Programme (Boats 5115 - 5132). However, all boats were cancelled in late 1943, because the IJN concentrated on production of Type-E submarine (戊型潜水艦, Bo-gata sensuikan) from 1945.
- Boats in class
Characteristics
References
Notes
Bibliography
- Milanovich, Kathrin (2021). "The IJN Submarines of the I 15 Class". In Jordan, John (ed.). Warship 2021. Oxford, UK: Osprey Publishing. pp. 29–43. ISBN 978-1-4728-4779-9.
- "Rekishi Gunzō"., History of Pacific War Vol.17 I-Gō Submarines, Gakken (Japan), January 1998, ISBN 4-05-601767-0
- Rekishi Gunzō, History of Pacific War Vol.35 Kō-hyōteki and Kōryū, Gakken (Japan), April 2002, ISBN 4-05-602741-2
- Rekishi Gunzō, History of Pacific War Vol.36 Kairyū and Kaiten, Gakken (Japan), May 2002, ISBN 4-05-602693-9
- Rekishi Gunzō, History of Pacific War Extra, "Perfect guide, The submarines of the Imperial Japanese Forces", Gakken (Japan), March 2005, ISBN 4-05-603890-2
- Model Art Extra No.537, Drawings of Imperial Japanese Naval Vessels Part-3, Model Art Co. Ltd. (Japan), May 1999, Book code 08734-5
- The Maru Special, Japanese Naval Vessels No.31 Japanese Submarines I, Ushio Shobō (Japan), September 1979, Book code 68343-31
