SM U-64 was a Type U-63 class submarine in the Kaiserliche Marine that served during World War I. She was built in 1916 and served in the Mediterranean Sea.
SM UC-4 was a German Type UC I minelayer submarine or U-boat in the German Imperial Navy during World War I. The U-boat had been ordered by November 1914 and was launched on 6 June 1915. She was commissioned into the German Imperial Navy on 10 June 1915 as SM UC-4. Mines laid by UC-4 in her 73 patrols were credited with sinking 36 ships. UC-4 was scuttled off the coast of Flanders during the German evacuation on 5 October 1918.
SM UC-17 was a German Type UC II minelaying submarine or U-boat in the Imperial German Navy in World War I. She was ordered on 29 August 1915 and launched on 29 February 1916. She was commissioned into the Imperial German Navy on 21 July 1916 as SM UC-17.
SM UC-20 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 29 August 1915 and was launched on 1 April 1916. She was commissioned into the German Imperial Navy on 7 September 1916 as SM UC-20. In 13 patrols UC-20 was credited with sinking 21 ships, either by torpedo or by mines laid. UC-20 was surrendered on 16 January 1919 and broken up at Preston in 1919–20.
SM UC-71 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 and was launched on 12 August 1916. She was commissioned into the German Imperial Navy on 28 November 1916 as SM UC-71. In 19 patrols UC-71 was credited with sinking 63 ships, either by torpedo or by mines laid. UC-71 sank on 20 February 1919 in the North Sea while on her way to be surrendered. Discovery a century later of her wreck with all hatches open suggested she had been deliberately scuttled by her own crew.
SM U-47 was a Type U-43 submarine of the Imperial German Navy. She engaged in commerce raiding during the First World War.
SM U-54 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-54 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-57 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-57 was engaged in naval warfare and took part in the First Battle of the Atlantic.
SM U-58 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-58 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-60 was a German Type UB III submarine of the Imperial German Navy in the First World War. She took part in the First Battle of the Atlantic.
SM U-62 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-62 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-65 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-65 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-73 was one of 329 submarines serving in the Imperial German Navy in World War I. She engaged in the commerce war as part of the First Battle of the Atlantic. U-73 has the distinction of being responsible for planting the underwater mine that later led to the sinking of the largest ship sunk during World War I, the 48,158 tons hospital ship Britannic.
SM U-101 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-101 was engaged in the German campaign against Allied commerce (Handelskrieg) during that conflict. On 26 November 1917, U-101 torpedoed and damaged RFA Crenella, which managed to return to port with assistance from USS Cushing.
SM U-22 was one of 329 submarines serving in the Imperial German Navy in World War I. U-22 was engaged in commerce war as part of the naval warfare, during the First Battle of the Atlantic.
SM U-23 was one of the 329 U-boats serving in the Imperial German Navy in World War I.
SM U-24 was one of 329 submarines serving in the Imperial German Navy in World War I. She was engaged in commerce warfare during the First Battle of the Atlantic.
SM U-50 was one of 329 submarines in the Imperial German Navy in World War I. She took part in the First Battle of the Atlantic.
SM U-52 was one of 329 submarines serving in the Imperial German Navy in World War I. U-52 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM UB-64 was a German Type UB III submarine or U-boat in the German Imperial Navy during World War I. She was commissioned into the German Imperial Navy on 5 August 1917 as SM UB-64.
German Empire 
