Black Swan sloops brought destroyer-like combat power

The Black Swan family was faster and more heavily armed than the corvettes and trawlers discussed earlier. Twin-shaft geared turbines let Modified Black Swans make about twenty knots while retaining a range near 7,500 nautical miles at twelve knots. They carried six 4-inch guns in twin mounts and layered light anti-aircraft weapons. The original outfit included forty depth charges, while Modified Black Swans carried as many as 110, and Squid appeared once the mortar entered service. The design omitted torpedoes but delivered overwhelming gun and anti-submarine power for an escort. Omitting torpedoes also let the Royal Navy build the type under Article 8's small-escort category. Compared with the Gabbiano, the Black Swan shows how treaty categories and theater requirements produced very different balances of speed, torpedoes, guns, and depth-charge firepower.