HMS ''R4'' was one of 10 R-class submarine built for the

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during the First World War. The boat was not completed before the end of the war and was sold for

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in 1934.

Design and description

The R-class submarine was designed to meet an

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requirement for a specialised

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with an emphasis on submerged performance. The boats had a length of overall, a

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of and a mean draft of . They displaced on the surface and submerged. The R-class submarines had a crew of 2 officers and 20 ratings.Gardiner & Gray, p. 93 They had a diving depth of . For surface running, the boats were powered by a single eight-cylinder

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that drove the single propeller shaft. When submerged it was driven by a

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. They could reach on the surface and underwater. On the surface, the R class had a range of at and at submerged.Harrison, Chapter 10 The boats were armed with six 18-inch (45 cm)

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s in the bow. They carried six reload torpedoes for a grand total of a dozen torpedoes. They were equipped with an array of five hydrophones in the bow to allow them to locate and engage targets while submerged.

Construction and career

HMS ''R4'' was laid down on 4 March 1917 at Chatham Dockyard, launched on 8 June 1918 and commissioned on 23 August 1919. She came too late to see any combat in

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, like most of the other R-class submarines. Her shape resulted in her being nicknamed "The Slug". On 1 November 1926, ''R4'' ran aground at

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. She was refloated 10½ hours later. ''R4'' was the only boat to survive through to the 1930s. Additions to her casing produced slightly better sea keeping at the cost of a reduced speed from 15 knots submerged to 13 knots. She was used as a fast underwater target at the

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anti-submarine school until 1934, then sold on 26 May 1934 to Young, Sunderland.

Notes

References

* * * * {{DEFAULTSORT:R04 British R-class submarines Royal Navy ship names 1918 ships Maritime incidents in 1926