The 20th Frigate Squadron was an administrative unit of the Royal Navy.
Operational history
A squadron of 4 frigates was established at Derry, Northern Ireland in 1961 initially comprising HMS Undaunted, HMS Falmouth, HMS Rothesay and HMS Blackwood. The squadron was responsible for the advanced training of officers in anti-submarine warfare and for the evaluation of modern anti-submarine equipment. Although operational from Derry, the ships assigned to the squadron continued to carry out their refits and intermediate dockings at their base ports (HMNB Devonport, Portsmouth and Rosyth).
During its service, the squadron included Type 14, Type 15 and Rothesay-class frigates.
References
20th Frigate Squadron (United Kingdom) Wikipedia(Text) CC BY-SA