Ships hit by U 21
See the profile page for U 21
| Date | U-boat | Commander | Name of ship | Type of ship | Tons | Nat. | ||
|---|---|---|---|---|---|---|---|---|
| 5 Sep 1914 | U 21 | Otto Hersing |  | Pathfinder (hms) | Light cruiser | 2,940 |  | br |
| 23 Nov 1914 | U 21 | Otto Hersing | Malachite | Steamer | 718 | | br | |
| 26 Nov 1914 | U 21 | Otto Hersing | Primo | Steamer | 1,366 | | br | |
| 30 Jan 1915 | U 21 | Otto Hersing | Ben Cruachan | Steamer | 3,092 | | br | |
| 30 Jan 1915 | U 21 | Otto Hersing | Kilcoan | Steamer | 456 | | br | |
| 30 Jan 1915 | U 21 | Otto Hersing | Linda Blanche | Steamer | 369 | | br | |
| 25 May 1915 | U 21 | Otto Hersing | | Triumph (hms) | Battleship | 11,985 | | br |
| 27 May 1915 | U 21 | Otto Hersing | | Majestic | Battleship | 14,900 | | br |
| 4 Jul 1915 | U 21 | Otto Hersing | | Carthage | Passenger steamer | 5,601 |  | fr |
| 1 Feb 1916 | U 21 | Otto Hersing | Belle Of France | Steamer | 3,876 | | br | |
| 8 Feb 1916 | U 21 | Otto Hersing | | Admiral Charner | Armored cruiser | 4,750 | | fr |
| 30 Apr 1916 | U 21 | Otto Hersing | City Of Lucknow | Steamer | 3,669 | | br | |
| 26 Oct 1916 | U 21 | Otto Hersing | Marina G. | Sailing vessel | 154 |  | it | |
| 28 Oct 1916 | U 21 | Otto Hersing | Gilda R. | Sailing vessel | 37 | | it | |
| 28 Oct 1916 | U 21 | Otto Hersing | Tre Fratelli D. | Sailing vessel | 190 | | it | |
| 31 Oct 1916 | U 21 | Otto Hersing | | Glenlogan | Steamer | 5,838 | | br |
| 1 Nov 1916 | U 21 | Otto Hersing | Bernardo Canale | Steamer | 1,346 | | it | |
| 1 Nov 1916 | U 21 | Otto Hersing | Torero | steamer | 767 | | it | |
| 2 Nov 1916 | U 21 | Otto Hersing | San Antonio O. | Sailing vessel | 113 | | it | |
| 3 Nov 1916 | U 21 | Otto Hersing | San Giorgio | Sailing vessel | 258 | | it | |
| 23 Dec 1916 | U 21 | Otto Hersing | Benalder (d.) | Steamer | 3,044 | | br | |
| 16 Feb 1917 | U 21 | Otto Hersing | Mayola | Sailing vessel | 146 | | br | |
| 16 Feb 1917 | U 21 | Otto Hersing | Rose Dorothea | Sailing vessel | 147 | | br | |
| 17 Feb 1917 | U 21 | Otto Hersing | Emilia I° | Sailing vessel | 25 |  | pt | |
| 17 Feb 1917 | U 21 | Otto Hersing | Lima | Sailing vessel | 108 | | pt | |
| 20 Feb 1917 | U 21 | Otto Hersing | Cacique | Steamer | 2,917 | | fr | |
| 22 Feb 1917 | U 21 | Otto Hersing | | Bandoeng | Steamer | 5,851 |  | nl |
| 22 Feb 1917 | U 21 | Otto Hersing | Eemland | Steamer | 3,770 | | nl | |
| 22 Feb 1917 | U 21 | Otto Hersing | Gaasterland | Steamer | 3,917 | | nl | |
| 22 Feb 1917 | U 21 | Otto Hersing | Jacatra | Steamer | 5,373 | | nl | |
| 22 Feb 1917 | U 21 | Otto Hersing | Noorderdijk | Steamer | 7,166 | | nl | |
| 22 Feb 1917 | U 21 | Otto Hersing | Normanna | Steamer | 2,900 |  | nw | |
| 22 Feb 1917 | U 21 | Otto Hersing | | Zaandijk | Steamer | 4,189 | | nl |
| 22 Feb 1917 | U 21 | Otto Hersing | | Menado (d.) | Steamer | 5,874 | | nl |
| 22 Apr 1917 | U 21 | Otto Hersing | Giskö | steamer | 1,643 | | nw | |
| 22 Apr 1917 | U 21 | Otto Hersing | Theodore William | Steamer | 3,057 | | nw | |
| 29 Apr 1917 | U 21 | Otto Hersing | Askepot | Sailing vessel | 1,793 | | nw | |
| 30 Apr 1917 | U 21 | Otto Hersing | Borrowdale | Sailing vessel | 1,268 |  | ru | |
| 3 May 1917 | U 21 | Otto Hersing | Lindisfarne | Sailing vessel | 1,703 | | ru | |
| 6 May 1917 | U 21 | Otto Hersing | Adansi | Steamer | 2,644 | | br | |
| 8 May 1917 | U 21 | Otto Hersing | Killarney | Sailing vessel | 1,413 | | br | |
| 27 Jun 1917 | U 21 | Otto Hersing | Baltic | Barge | 1,125 |  | sw | |
| 122,498 | ||||||||
| 40 ships sunk (113,580 tons) and 2 ships damaged (8,918 tons).
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