| 1938 | Seal (N37) | Launched |
| 1938 | Talisman (N78) | Laid Down |
| 1939 | Seal (N37) | HMS Seal ended her 2nd war patrol at Aden |
| 1940 | Unique (N95) | Completed |
| 1941 | Tetrarch (N77) | HMS Tetrarch sinks the Greek sailing vessel Panagiotis Kramottos with gunfire south-west of Milos Island, Greece. |
| 1941 | Upright (N89) | HMS Upright torpedoed and sank the Italian torpedo boat Albatros 8 nautical miles north-west of Cape Rasocolmo near Milazzo, Sicily, Italy. |
| 1941 | Una (N87) | Completed |
| 1942 | Umbra (P35) | HMS Umbra torpedoes and sinks the Italian merchant Francesco Barbaro some 50 nautical miles south-west of Cape Marathia, Zakynthos Island, Greece. |
| 1943 | Uproar (P31) | HMS Uproar torpedoes and further damages the grounded German tanker Champagne off Bastia, Corsica, France. |
| 1944 | Thorough (P324) | HMS Thorough sinks a small Japanese vessel north of Sumatra. |
| 1944 | Vigorous (P74) | HMS Vigorous torpedoes and sinks the German merchant Salomea and the German ferry SF 121 off Kassandra, Greece. |
| 1962 | Onyx (Ojibwa) | Laid Down |
| 1965 | HMCS Onondaga | HMCS Onondaga launched Chatham UK |