SM UC-48 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 20 November 1915, laid down on 1 February 1916, and was launched on 27 September 1916. She was commissioned into the German Imperial Navy on 6 November 1916 as SM UC-48.[1] In 13 patrols UC-48 was credited with sinking 35 ships, either by torpedo or by mines laid. UC-48 was severely damaged by a depth charge attack by on 20 March 1918 that ruptured the fuel tanks. Unable to return to Zeebrugge, the boat was steered to Ferrol, Spain, where she and her crew were interned for the rest of the war. The Spanish authorities removed UC-48s propellers to prevent any attempts at leaving port.
A Type UC II submarine, UC-48 had a displacement of 420t when at the surface and 502t while submerged. She had a length overall of 51.85m (170.11feet), a beam of 5.22m (17.13feet),and a draught of 3.68m (12.07feet). The submarine was powered by two six-cylinder four-stroke diesel engines each producing 300PS (a total of 600PS), two electric motors producing 460PS, and two propeller shafts. She had a dive time of 48 seconds and was capable of operating at a depth of .
The submarine had a maximum surface speed of and a submerged speed of . When submerged, she could operate for at ; when surfaced, she could travel at . UC-48 was fitted with six mine tubes, eighteen UC 200 mines, three torpedo tubes (one on the stern and two on the bow), seven torpedoes, and one 8.8sp=usNaNsp=us Uk L/30 deck gun. Her complement was twenty-six crew members.
| Date | Name | Nationality | Tonnage[2] | Fate[3] | |
|---|---|---|---|---|---|
| 16 March 1917 | Pencaer |  United Kingdom | 59 | Sunk | |
| 16 March 1917 | William Martyn | United Kingdom | 104 | Sunk | |
| 17 March 1917 | Antony | United Kingdom | 6,466 | Sunk | |
| 17 March 1917 | Guard | United Kingdom | 38 | Sunk | |
| 21 March 1917 | Rio Sorocaba | United Kingdom | 4,307 | Sunk | |
| 22 March 1917 | Chorley | United Kingdom | 3,828 | Sunk | |
| 22 March 1917 | Providence | United Kingdom | 2,970 | Sunk | |
| 23 March 1917 | J. B. August Kessler |  Netherlands | 5,104 | Damaged | |
| 25 March 1917 | HMT Evangel | 197 | Sunk | ||
| 27 April 1917 | Amelia & Jane | United Kingdom | 62 | Damaged | |
| 1 May 1917 | Raymond Ester |  France | 20 | Sunk | |
| 2 May 1917 | United | United Kingdom | 61 | Sunk | |
| 2 May 1917 | Warnow | United Kingdom | 1,593 | Sunk | |
| 5 May 1917 | Feltria | United Kingdom | 5,254 | Sunk | |
| 5 May 1917 | Greta | United Kingdom | 297 | Sunk | |
| 7 May 1917 | Kinross | United Kingdom | 4,120 | Sunk | |
| 9 June 1917 | Amphitrite |  Portugal | 179 | Sunk | |
| 10 June 1917 | Solhaug |  Norway | 1,217 | Sunk | |
| 13 June 1917 | Ernestine | France | 160 | Sunk | |
| 15 June 1917 | Eugene Et Eugenie | France | 46 | Sunk | |
| 16 June 1917 | John D. Archbold |  United States | 8,374 | Sunk | |
| 17 June 1917 | Anjou | 771 | Sunk | ||
| 17 June 1917 | Antonios M. Mavrogordatos |  Greece | 3,771 | Sunk | |
| 18 June 1917 | Tyne | United Kingdom | 2,909 | Sunk | |
| 15 July 1917 | Florence Creadick | United States | 732 | Damaged | |
| 15 July 1917 | Westmeath | United Kingdom | 9,179 | Damaged | |
| 16 July 1917 | Henry R. James | United Kingdom | 3,146 | Sunk | |
| 18 August 1917 | Dunkerquois | France | 2,087 | Sunk | |
| 19 August 1917 | Monksgarth | United Kingdom | 1,928 | Sunk | |
| 19 August 1917 | Ytterøy | Norway | 1,112 | Sunk | |
| 16 September 1917 | Sandsend | United Kingdom | 3,814 | Sunk | |
| 17 September 1917 | Our Bairns | United Kingdom | 50 | Sunk | |
| 17 September 1917 | Ronald | United Kingdom | 38 | Sunk | |
| 19 September 1917 | Etal Manor | United Kingdom | 1,875 | Sunk | |
| 21 September 1917 | Kouang-Si | France | 6,472 | Damaged | |
| 14 October 1917 | Barbro | Norway | 2,356 | Sunk | |
| 14 October 1917 | Castro | Greece | 1,994 | Sunk | |
| 15 October 1917 | Hovde | Norway | 1,196 | Sunk | |
| 22 October 1917 | Aizcorri Mendi |  Spain | 2,272 | Damaged | |
| 17 November 1917 | Modemi | Norway | 1,481 | Sunk | |
| 30 January 1918 | Ange Gardien | France | 24 | Sunk |