Events
On This Day - April 23
| 1890 | 1891 - 1920: St George | Laid down |
| 1914 | E11 | Launched |
| 1914 | E15 | Launched |
| 1918 | C1 | Filled with dynamite and scheduled to be blown up at Zeebrugge Mole but was spared |
| 1940 | Tetrarch (N77) | 18:30 Sighted a Southbound enemy convoy bearing 270, distance about 5 nautical miles. The convoy was made up of a large merchant vessel and three escorts. They are described as destroyers in the patrol report but they were not destroyers. The vessels were Ahrensburg on passage from Larvik to Fredrikshaven according to Rowher, escorted by T153, T155, F5, F8 and the minesweepers R33, R37 and R40 18:33 Tetrarch fired two torpedoes, range 4,000 yards, flat calm. Went deep and retired at high speed. 1837: Returned to periscope depth. Three escorting destroyers were seen approaching down the torpedo tracks a high speed. One of the destroyers was only 1500 yards away. Tetrarch went to 300 feet at full speed. Trim lost. Mills temporarily lost control and the boat dived to 400' At 20:00 hours A/S trawlers joined in the hunt for Tetrarch 22:22 Surfaced, sighted two trawlers 1,000 yards away bearing down fast. Two torpedoes were fired. One one torpedo hit the UB boat. German sources indicate just three survivors. Tetrarch was kept down at night and was therefore unable to charge batteries. Tetrarch eventually surfaced at 2130 hours on 24 April 1940 and set course back to Rosyth |
| 1943 | Sickle (P224) | HMS Sickle fires two torpedoes against the Italian merchant Mauro Croce off Sagunto, Spain. The torpedoes ran under the target and Sickle fired 19 rounds with her deck gun but failed to hit the target. |
| 1943 | Syrtis (P241) | Completed |
| 1943 | Vagabond (P18) | Laid Down |
| 1945 | Seneschal (P255) | Launched |
| 2014 | Vigilant (S30) | HMS Vigilant returned from patrol to her home on the Clyde |
