U-56 may refer to one of the following German submarines:
Germany, officially the Federal Republic of Germany, is a country in Central and Western Europe, lying between the Baltic and North Seas to the north, and the Alps to the south. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, France to the southwest, and Luxembourg, Belgium and the Netherlands to the west.
- SM U-56, a Type U 51 submarine launched in 1916 and that served in the First World War until she went missing after 3 November 1916
- During the First World War, Germany also had these submarines with similar names:
- SM UB-56, a Type UB III submarine launched in 1917 and sunk on 19 December 1917
- SM UC-56, a Type UC II submarine launched in 1916 and interned at Santander, Spain, on 24 May 1918. UC-56 sank the British hospital ship Glenart Castle on 26 February 1918.
HMHS Glenart Castle was a steamship originally built as Galician in 1900 for the Union-Castle Line. She was renamed Glenart Castle in 1914, but was requisitioned for use as a British hospital ship during the First World War. On 26 February 1918, she was hit and sunk by a torpedo fired from the German U-boat UC-56.
The Type UB III submarine was a class of U-boat built during World War I by the German Imperial Navy.
SM UC-56 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 12 January 1916, laid down on 4 March 1916, and was launched on 26 August 1916. She was commissioned into the German Imperial Navy on 18 December 1916 as SM UC-56. In 6 patrols UC-56 was credited with sinking 1 ship by torpedo: the British hospital ship Glenart Castle. UC-56 suffered from mechanical breakdowns that prevented her from submerging. She put in at Santander, Spain, on 24 May 1918 and was interned there for the duration of the war.
Type UC II minelaying submarines were used by the Imperial German Navy during World War I. They displaced 417 tons, carried guns, 7 torpedoes and up to 18 mines. The ships were double-hulled with improved range and seakeeping compared to the UC I type.
- During the First World War, Germany also had these submarines with similar names:
- German submarine U-56 (1938), a Type IIC submarine that served in the Second World War until sunk 28 April 1945
SM U-56 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-56 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
World War I, also known as the First World War or the Great War, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918. Contemporaneously described as "the war to end all wars", it led to the mobilisation of more than 70 million military personnel, including 60 million Europeans, making it one of the largest wars in history. It is also one of the deadliest conflicts in history, with an estimated nine million combatants and seven million civilian deaths as a direct result of the war, while resulting genocides and the 1918 influenza pandemic caused another 50 to 100 million deaths worldwide.
SM UB-56 was a German Type UB III submarine or U-boat in the German Imperial Navy during World War I. She was commissioned into the Flanders Flotilla of the German Imperial Navy on 19 July 1917 as SM UB-56.
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