The Egret and Black Swan classes refined the Bittern lineage while remaining compact naval-standard warships. Prewar exercises and deployments revealed what guns, depth charges, accommodation, and seakeeping a useful escort required. The Admiralty could transfer those tested requirements to Flower-class corvettes and armed trawlers ordered from commercial yards. Peacetime presence ships therefore supplied practical evidence for wartime mass production.
Chapter · 44:08-48:47
Black Swan experience underpinned wartime escorts
Successive naval-standard sloops let the Royal Navy test weapons and arrangements later transferred to merchant-standard wartime escorts.