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| Class overview | |
|---|---|
| Name | Type L submarines |
| Builders | Mitsubishi Heavy Industries-Kōbe Shipyard |
| Operators |  Imperial Japanese Navy |
| Subclasses |
|
| Built | 1918-1927 |
| In commission | 1920-1945 |
TheType L submarine (L型潜水艦,L-gata Sensuikan) submarines were medium-sized submarines of theImperial Japanese Navy (IJN), serving during the 1920s andWorld War II. TheType L submarines were built withVickers naval technical guidance. All boats were built in theMitsubishi Heavy Industries-Kobe Shipyard by the contract with Vickers.
TheType L submarines were divided into four classes:
In 1916, theMitsubishi Shipbuilding Corporation got the VickersL class submarine informations. Mitsubishi which lost competition to theKawasaki'sType F submarines (Fiat-Laurenti design,Ro-1 class andRo-3 class), bought the license for theL 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 thediesel engines and made many variants of similar design, for example:Kampon Mk.24 diesel for theRo-100 class.
| Boat | Laid down | Launched | Completed | Note, fate |
|---|---|---|---|---|
| Ro-51[1] ex-Submarine No. 25 | 10–08–1918 | 10–10–1919 | 30–06–1920 | RenamedRo-51 01–11–1924. Decommissioned 01–04–1940. |
| Ro-52 ex-Submarine No. 26 | 10–08–1918 | 09–03–1920 | 30–11–1920 | RenamedRo-52 01–11–1924. Decommissioned 01–04–1932. |
TheType L2 had minor changes from theType L1. The changes were:
| Boat | Laid down | Launched | Completed | Note, fate |
|---|---|---|---|---|
| Ro-53 ex-Submarine No. 27 | 01–04–1919 | 06–07–1919 | 10–03–1921 | RenamedRo-53 01–11–1924. Decommissioned 01–04–1940. |
| Ro-54 ex-Submarine No. 28 | 01–11–1919 | 13–11–1920 | 10–09–1921 | RenamedRo-54 01–11–1924. Decommissioned 01–04–1940. |
| Ro-55 ex-Submarine No. 29 | 30–03–1920 | 10–02–1921 | 15–11–1921 | RenamedRo-55 01–11–1924. Decommissioned 01–04–1940. |
| Ro-56 ex-Submarine No. 30 | 10–07–1920 | 11–05–1921 | 16–01–1922 | RenamedRo-56 01–11–1924. Decommissioned 01–04–1940. |
TheType L3 is a license production model of the BritishL class submarine Group 2.
| Boat | Laid down | Launched | Completed | Results | Note, fate |
|---|---|---|---|---|---|
| Ro-57 ex-Submarine No. 46 | 20–11–1920 | 03–12–1921 | 30–07–1922 | RenamedRo-57 01–11–1924. Decommissioned 20–11–1945. Later scuttled offKure. | |
| Ro-58 ex-Submarine No. 47 | 15–02–1921 | 02–03–1922 | 25–11–1922 | RenamedRo-58 01–11–1924. Decommissioned 15–09–1945. Later scuttled offShimizu. | |
| Ro-59 ex-Submarine No. 57 | 18–05–1921 | 28–06–1922 | 20–03–1923 | RenamedRo-59 01–11–1924. Decommissioned 20–11–1945. Scuttled atIyo-nada, May 1946. |
TheType L4 is a license production model of the BritishL class submarine Group 3. Their performance was good. The IJN was satisfied with them and stopped the development ofKaichū 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 thePacific War.
| Boat | Laid down | Launched | Completed | Results | Note, fate |
|---|---|---|---|---|---|
| Ro-60 ex-Submarine No. 59 | 05–12–1921 | 20–12–1922 | 17–09–1923 | RenamedRo-60 01–11–1924. Lost in an accident atKwajalein 29–12–1941. | |
| Ro-61 ex-Submarine No. 72 | 05–06–1922 | 19–05–1923 | 09–02–1924 | DamagedUSS Casco 30–08–1942 | RenamedRo-61 01–11–1924. Sunk byUSS Reid 31–08–1942. |
| Ro-62 ex-Submarine No. 73 | 08–09–1922 | 29–09–1923 | 24–07–1924 | RenamedRo-62 01–11–1924. Decommissioned 20–11–1945. Scuttled at Iyo-nada, May 1946. | |
| Ro-63 ex-Submarine No. 84 | 02–04–1923 | 24–01–1924 | 20–12–1924 | RenamedRo-63 01–11–1924. Decommissioned 20–11–1945. Scuttled at Iyo-nada, May 1946. | |
| Ro-64 ex-Submarine No. 79 | 15–10–1923 | 19–08–1924 | 30–04–1925 | RenamedRo-64 01–11–1924. Sunk by naval mine atHiroshima Bay 12–04–1945. | |
| Ro-65 | 15–11–1924 | 19–09–1925 | 30–06–1926 | Lost in an accident atKiska 04–11–1942. | |
| Ro-66 | 01–12–1925 | 25–10–1926 | 28–07–1927 | Collided withRo-62 and sunk southwest ofWake Island 17–12–1941. | |
| Ro-67 | 05–03–1925 | 18–03–1926 | 15–12–1926 | Decommissioned 20–07–1945. Scuttled offSasebo, July 1948. | |
| Ro-68 | 06–02–1924 | 23–02–1925 | 29–10–1925 | Decommissioned 30–11–1945. Scuttled offMaizuru, 30–04–1946. |
| 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 | 1,075.2 long tons (1,092 t) | 1,075.3 long tons (1,093 t) | 1,102.7 long tons (1,120 t) | 1,301 long tons (1,322 t) | |
| Length (overall) | 70.59 m (231 ft 7 in) | 70.59 m (231 ft 7 in) | 72.89 m (239 ft 2 in) | 78.39 m (257 ft 2 in) | |
| Beam | 7.16 m (23 ft 6 in) | 7.16 m (23 ft 6 in) | 7.16 m (23 ft 6 in) | 7.41 m (24 ft 4 in) | |
| Draft | 3.90 m (12 ft 10 in) | 3.94 m (12 ft 11 in) | 3.96 m (13 ft 0 in) | 3.96 m (13 ft 0 in) | |
| 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 | 17knots (31 km/h) | 17.3knots (32.0 km/h) | 17.1knots (31.7 km/h) | 15.7knots (29.1 km/h) |
| Submerged | 10.2knots (18.9 km/h) | 10.4knots (19.3 km/h) | 9.1knots (16.9 km/h) | 8.6knots (15.9 km/h) | |
| Range | Surfaced | 5,500 nmi (10,200 km) at 10 knots (19 km/h) | 5,500 nmi (10,200 km) at 10 knots (19 km/h) | 5,500 nmi (10,200 km) at 10 knots (19 km/h) | 5,500 nmi (10,200 km) at 10 knots (19 km/h) |
| Submerged | 80 nmi (150 km) at 4 knots (7.4 km/h) | 80 nmi (150 km) at 4 knots (7.4 km/h) | 80 nmi (150 km) at 4 knots (7.4 km/h) | 80 nmi (150 km) at 4 knots (7.4 km/h) | |
| Test depth | 60 m (200 ft) | 60 m (200 ft) | 60 m (200 ft) | 60 m (200 ft) | |
| Fuel | 75 tons | 75 tons | 75 tons | 75 tons | |
| Complement | 45 | 45 | 46 | 48 | |
| Armament (initial) | • 6 × 450 mm (18 in)TTs (4 × bow, 2 × broadside) • 10 × Type 44 torpedoes • 1 ×76.2 mm (3.00 in)L/23.5 AA gun | • 4 × 450 mm TTs (4 × bow) • 8 × Type 44 torpedoes • 1 × 76.2 mm L/23.5 AA gun | • 4 × 533 mm (21 in) TTs (4 × bow) • 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 × bow) • 12 × 6th Year Type torpedoes • 1 ×76.2 mm (3.00 in) L/40 naval gun • 1 × 6.5 mm machine gun | |