SM U-35 was a German U 31-class U-boat which operated in the Mediterranean Sea during World War I. It ended up being the most successful U-boat participating in the war, sinking 220 merchant ships for a total of 505,121 gross register tons (GRT).
Type U 31 was a class of U-boats built during World War I by the Kaiserliche Marine.
SM U-83 was a Type U 81 U-boat of the German Imperial Navy during the First World War. She had been commissioned and deployed to operate off the coast of the British Isles and attack coastal shipping as part of the German U-boat campaign.
SM UC-1 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 26 April 1915. She was commissioned into the German Imperial Navy on 5 July 1915 as SM UC-1. Mines laid by UC-1 in her 80 patrols were credited with sinking 41 ships. UC-1 disappeared after 18 July 1917. UC-1 was sunk on 24 July 1917 by F2B Felixstowe flying boat. Standard practice was to fly along the U boat and drop 2 250lb bombs astride it, hoping to cause leaks and give time for a destroyer to collect the submariners and sink it. On this occasion, by fluke, one bomb went through the conning tower and blew the base out of UC1. MFG Mill was awarded the DFC for this but he refused to wear it because of the total loss of life <london Gazette> <MFG Mill Diaries>
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-11 was a German Type UC I minelayer submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 23 November 1914, laid down on 26 January 1915, and was launched on 11 April 1915. She was commissioned into the German Imperial Navy on 23 April 1915 as SM UC-11. Mines laid by UC-11 in her 83 patrols were credited with sinking 27 ships. UC-11 was mined and sunk on 26 June 1918. A crew member was Rudolf Finkler from Oberlinxweiler, Kreis St. Wendel, Germany. According to his death record the boat went down in the North Sea near Harwich, abt. 2.5 nautical miles north east of Funk Feuerschiff on position 51°55′N1°41′E.
SM UC-14 was a German Type UC I minelayer submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 23 November 1914, laid down on 28 January 1915, and was launched on 13 May 1915. She was commissioned into the German Imperial Navy on 5 June 1915 as SM UC-14. Mines laid by UC-14 in her 38 patrols were credited with sinking 16 ships, one of which was the Italian pre-dreadnought battleship Regina Margherita, which at 13,427 tonnes displacement was one of the largest ships sunk by U-boats during the war. UC-14 was mined and sunk on 3 October 1917.
SM UB-23 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 30 April 1915 and launched on 9 October 1915. She was commissioned into the Imperial German Navy on 13 March 1916 as SM UB-23. The submarine sank 51 ships in 21 patrols for a total of 33,880 gross register tons (GRT). On 26 July 1917, UB-23 was badly damaged by a depth charge attack by HMS PC-60 off the Lizard; she put in at Corunna, Spain, on 29 July 1917 and was interned. On 22 January 1919 she was surrendered to France in accordance with the requirements of the Armistice with Germany, and she was broken up in Cherbourg in July 1921.
SM UB-30 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 22 July 1915 and launched on 16 November 1915. She was commissioned into the German Imperial Navy on 18 March 1916 as SM UB-30.
SM UB-35 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 22 July 1915 and launched on 28 December 1915. She was commissioned into the German Imperial Navy on 22 June 1916 as SM UB-35.
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-22 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 February 1916. She was commissioned into the German Imperial Navy on 30 June 1916 as SM UC-22. In 15 patrols UC-22 was credited with sinking 23 ships, either by torpedo or by mines laid. UC-22 was surrendered to France on 3 February 1919 and was broken up at Landerneau in July 1921.
SM UC-25 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 10 June 1916. She was commissioned into the German Imperial Navy on 28 June 1916 as SM UC-25. In 13 patrols UC-25 was credited with sinking 21 ships, either by torpedo or by mines laid. From March to September 1918, she was commanded by Karl Dönitz, later grand admiral in charge of all U-boats in World War II. UC-25 was scuttled at Pola on 28 October 1918 on the surrender of Austria-Hungary.
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-80 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-80 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-97 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-97 was engaged in the naval warfare and took part in the First Battle of the Atlantic. The German unit sank by accident on her way to surrender at position 53°25′N3°10′E.
SM U-98 was a Type U 93 submarine and one of the 329 submarines serving in the Imperial German Navy in World War I. U-98 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.
SM UB-128 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 11 May 1918 as SM UB-128.
German Empire 
