Japanese submarine Ro-55 (1921)

History
Japan
NameSubmarine No. 29
BuilderMitsubishi, Kobe, Japan
Laid down30 March 1920
Launched10 February 1921
Completed15 November 1921
Commissioned15 November 1921
RenamedRo-55 on 1 November 1924
Decommissioned1 April 1926
Recommissioned1 August 1926
Decommissioned15 December 1938
Stricken1 April 1940
General characteristics
Class and typeJapanese Type L submarine (L2 subclass)
Displacement
  • 907 tonnes (893 long tons) surfaced
  • 1,093 tonnes (1,075.3 long tons) submerged
Length70.59 m (231 ft 7 in) overall
Beam7.16 m (23 ft 6 in)
Draft3.94 m (12 ft 11 in)
Installed power
Propulsion
Speed
  • 17.3 knots (32.0 km/h; 19.9 mph) surfaced
  • 10.4 knots (19.3 km/h; 12.0 mph) submerged
Range
  • 5,500 nmi (10,200 km; 6,300 mi) at 10 knots (19 km/h; 12 mph) surfaced
  • 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth60 m (197 ft)
Crew45
Armament

The first Ro-55, originally named Submarine No. 29, was an Imperial Japanese Navy Type L submarine of the L2 subclass. Except for a few months in 1926, she was in commission from 1921 to 1938.

Design and description

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The submarines of the Type L2 sub-class were close copies of the British L-class submarine built under license in Japan. They differed from the preceding L1 subclass in the deletion of the two broadside-firing torpedo tubes and the two torpedoes for them, the use of domestically produced diesel engines and batteries, and a different battery arrangement. They displaced 907 tonnes (893 long tons) surfaced and 1,093 tonnes (1,075.3 long tons) submerged. The submarines were 70.59 meters (231 ft 7 in) long and had a beam of 7.16 meters (23 ft 6 in) and a draft of 3.94 meters (12 ft 11 in). They had a diving depth of 60 meters (197 ft).

For surface running, the submarines were powered by two 1,200-brake-horsepower (895 kW) Vickers diesel engines, each driving one propeller shaft. When submerged, each propeller was driven by an 800-shaft-horsepower (597 kW) electric motor. They could reach 17.3 knots (32.0 km/h; 19.9 mph) on the surface and 10.4 knots (19.3 km/h; 12.0 mph) underwater. On the surface, they had a range of 5,500 nautical miles (10,200 km; 6,300 mi) at 10 knots (19 km/h; 12 mph); submerged, they had a range of 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph).

The submarines were armed with four internal 450 mm (18 in) torpedo tubes, all in the bow, and carried a total of eight Type 44 torpedoes. They were also armed with a single 76.2 mm (3 in) deck gun.

Construction and commissioning

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Ro-55 was laid down as Submarine No. 29 on 30 March 1920 by Mitsubishi at Kobe, Japan.[1] Launched on 10 February 1921,[1] she was completed and commissioned on 15 November 1921.[1]

Service history

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Upon commissioning, Submarine No. 29 was attached to the Yokosuka Naval District.[1] On 1 December 1921, she was reassigned to Submarine Division 4 in Submarine Squadron 1 in the 1st Fleet.[1] She was renamed Ro-55 on 1 November 1924.[1] Submarine Division 4 was reattached to the Yokosuka Naval District on 1 December 1925, and Ro-55 and was assigned that day to the Yokosuka Defense Division.[1] She was decommissioned and placed in reserve on 1 April 1926.[1]

Ro-55 was recommissioned on 1 August 1926, and was assigned to the Yokosuka Defense Division that day, serving in that duty until 1 December 1927.[1] She later served in the Yokosuka Defense Division again from 30 November 1929 to 15 November 1934.[1]

Ro-55 was decommissioned and placed in the Fourth Reserve in the Yokosuka Naval District on 15 December 1938.[1] The Japanese struck her from the Navy list on 1 April 1940.[1]

Notes

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  1. ^ a b c d e f g h i j k l "RO-55 ex No-29". iijnsubsite.info. 2018. Retrieved 11 October 2020.

Bibliography

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  • "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
  • 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