Events
On This Day - March 23
| 1905 | A6 | Completed |
| 1906 | B10 | Launched |
| 1912 | D8 | Completed |
| 1922 | H42 | Sunk in Collision with HMS Versatile off Gibraltar As part of the 3rd Submarine Flotilla H42 had spent Christmas 1921 in Portsmouth before sailing in January 1922 for exercises in the Mediterranean. H42 surfaced just off Gibraltar 120 yards in front of the destroyer HMS Versatile who at that time was cruising at 20 knots. The Destroyer was unable to take avoiding action and ploughed into the submarine almost slicing her in two. |
| 1942 | Unison (P43) | HMS Unison torpedoes and sinks the Italian tanker Zeila off Cape Spartivento. |
| 1943 | Sidon (P259) | Sidon arrived back at Lerwick after completing her working up patrol. |
| 1943 | Sahib (P212) | HMS Sahib torpedoes ans sinks the small Italian merchant Tosca west of Cape Calava, Sicily, Italy. |
| 1943 | Stonehenge (P232) | Launched |
| 1943 | Talent (P322) | Transferred to the Royal Netherlands Navy. |
| 1944 | Urtica (P83) | Launched |
| 1945 | P553 | Sunk as target |
