What could a Black Swan-class sloop do with three twin 4.5-inch gun mounts?
Short answerIt would become an exceptionally strong convoy escort with ASW, surface, and air-defense capability, close to a destroyer in fighting power.
NotesThe proposed armament would add radar-directed surface and air-defence firepower to an already capable anti-submarine escort. With three twin 4.5-inch mounts, the ship could fight destroyers while remaining dangerous to aircraft and submarines. Adding torpedoes would complete its convergence toward a Daring-class destroyer. On east-coast convoy duty, its long-range gunfire would also make it a formidable answer to Schnellboote. That strength creates a mission tradeoff, because commanders might divert a premier ASW escort toward surface and air-defence work.