The class displaced well below 2,000 tons and reached about 19 to 20 knots while steaming 7,500 nautical miles at economical speed. Three twin four-inch mounts gave useful dual-purpose fire, supplemented by pom-poms and later Oerlikons. Modified ships carried as many as 110 depth charges, giving them a formidable anti-submarine outfit on a compact hull. Their hull relationship with the Hunt-class escort destroyers also illustrates how a sustained sloop program could support later fleet needs.
Chapter · 45:39-47:31
Black Swan capability on a common hull
The Black Swan class combined long range, twin four-inch guns, light AA, and a large depth-charge outfit on a treaty-compatible hull shared with Hunt-class escorts.