SM UC-53 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 12 January 1916 and was launched on 27 February 1917. She was commissioned into the German Imperial Navy on 5 April 1917 as SM UC-53.[1] In eight patrols UC-53 was credited with sinking 47 ships, either by torpedo or by mines laid. UC-53 was scuttled at Pola on 28 October 1918 on the surrender of Austria-Hungary.
A Type UC II submarine, UC-53 had a displacement of 434t when at the surface and 511t while submerged. She had a length overall of 52.69m (172.87feet), a beam of 5.22m (17.13feet), and a draught of 3.64m (11.94feet). The submarine was powered by two six-cylinder four-stroke diesel engines each producing 290PS300PS (a total of 580PS600PS), two electric motors producing 620PS, 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-53 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] | |
|---|---|---|---|---|---|
| 4 June 1917 | City of Baroda |  United Kingdom | 5,032 | Sunk | |
| 9 June 1917 | Lilly |  Denmark | 1,150 | Sunk | |
| 9 June 1917 | Tordenvore |  Norway | 1,565 | Sunk | |
| 10 June 1917 | Ligeiro |  Portugal | 285 | Damaged | |
| 10 June 1917 | Santa Maria | Portugal | 204 | Sunk | |
| 11 June 1917 | Sibens | 323 | Sunk | ||
| 12 June 1917 | Symra | Norway | 3,005 | Sunk | |
| 16 June 1917 | Esperanza |  Spain | 98 | Sunk | |
| 16 June 1917 | F.7.SB. | Spain | 50 | Sunk | |
| 21 June 1917 | Nord |  France | 3,193 | Damaged | |
| 9 August 1917 | Canara | United Kingdom | 6,012 | Damaged | |
| 10 August 1917 | Margherita | 66 | Sunk | ||
| 10 August 1917 | Tito Speri | 3,893 | Sunk | ||
| 13 August 1917 | Arcangelo Michele | 45 | Sunk | ||
| 12 August 1917 | Ansedonia | 270 | Sunk | ||
| 12 August 1917 | Ardita Carrara | 75 | Sunk | ||
| 13 August 1917 | Il Nuovo Leonardo | 34 | Sunk | ||
| 15 September 1917 | Cavi | 2,544 | Damaged | ||
| 18 September 1917 | Domenico Primo | 80 | Damaged | ||
| 19 September 1917 | Teresita | 136 | Sunk | ||
| 21 September 1917 | Christina | 32 | Sunk | ||
| 22 September 1917 | Primo | 65 | Sunk | ||
| 23 September 1917 | Argietta | 165 | Sunk | ||
| 23 September 1917 | Giuseppina Concettina | 31 | Sunk | ||
| 23 September 1917 | Irthington | United Kingdom | 2,845 | Sunk | |
| 24 September 1917 | Nuova Francesca | 45 | Sunk | ||
| 24 September 1917 | S. Espedito | 31 | Sunk | ||
| 8 December 1917 | Giuseppe Naccari | 128 | Sunk | ||
| 9 December 1917 | Cerea | 4,295 | Damaged | ||
| 9 December 1917 | Costas |  Greece | 3,278 | Sunk | |
| 10 December 1917 | Antonio Magliulo | 520 | Sunk | ||
| 13 December 1917 | Karen | Norway | 1,689 | Sunk | |
| 14 December 1917 | HMS Brig 1 | 120 | Damaged | ||
| 25 December 1917 | Hekla | Denmark | 937 | Sunk | |
| 25 January 1918 | Carignano | 2,688 | Sunk | ||
| 26 January 1918 | Asimina | Greece | 2,878 | Sunk | |
| 29 January 1918 | Geo | United Kingdom | 3,048 | Sunk | |
| 30 January 1918 | Fratelli Barrera | 88 | Sunk | ||
| 30 January 1918 | Michele Padre | 230 | Sunk | ||
| 24 March 1918 | La Nuova Felice | 72 | Sunk | ||
| 24 March 1918 | Nuovo Genio | 35 | Sunk | ||
| 24 March 1918 | Regina Immacolata | 36 | Sunk | ||
| 24 March 1918 | Tre Sorelle Salvo | 26 | Sunk | ||
| 27 March 1918 | Castrenzo Coppola | 94 | Sunk | ||
| 4 June 1918 | Michelangelo | 2,456 | Damaged | ||
| 8 June 1918 | Concettina | 1,271 | Sunk | ||
| 8 June 1918 | La Bayonnaise | France | 2,425 | Sunk | |
| 10 June 1918 | Brodholme | United Kingdom | 5,747 | Damaged | |
| 22 September 1918 | Gorsemore | United Kingdom | 3,079 | Sunk | |
| 28 September 1918 | Caraibe | France | 2,976 | Damaged | |
| 30 September 1918 | Francesco Padre | 101 | Sunk | ||
| 30 September 1918 | Gabriela Costela | 105 | Sunk | ||
| 30 September 1918 | Giovanni Costa | 102 | Sunk | ||
| 30 September 1918 | San Francesco P. | 41 | Sunk | ||
| 1 October 1918 | Giuseppino M. | 48 | Sunk | ||
| 1 October 1918 | S. Giuseppe A. | 56 | Sunk | ||
| 5 October 1918 | Rosa | 908 | Damaged | ||
| 20 November 1918 | War Typhoon | United Kingdom | 3,116 | Damaged | |
| 15 January 1919 | Chaouia | France | 4,334 | Sunk |