Castle corvettes and the speed problem

The Castle class was only a little larger than the Flower, with slightly more beam and a shallower draft. Official power and speed figures give one baseline, while service accounts report some ships reaching about 18 knots. Those claims remain uncertain and do not establish uniform performance across the class. Even a modest increase mattered because an escort that broke away to attack still had to regain its convoy. Speed, seakeeping dimensions, and mission endurance therefore had to be judged together.