The technical details of British warships were recorded in a set of plans produced by the builders on completion of every ship. Known as the ‘as fitted’ general arrangements, these drawings represented the exact appearance and fitting of the ship as it entered service. Intended to provide a permanent reference for the Admiralty and the dockyards, these highly detailed plans were drawn with exquisite skill in multi-coloured inks and washes that represent the acme of the draughtsman’s art. Today they form part of the incomparable collection of the National Maritime Museum at Greenwich, which is using the latest scanning technology to make digital copies of the highest quality. This book is one of a series based entirely on these draughts which depict famous warships in an unprecedented degree of detail – complete sets in full colour, with many close-ups and enlargements that make every aspect clear and comprehensible. Extensive captions point the reader to important features to be found in the plans, and an introduction covers the background to the design. This volume is devoted to the sloops of the _Black Swan_ class and its improved derivatives, widely regarded as the ‘Rolls-Royce’ of Second World War convoy escorts. Heavily armed and superbly equipped for their role, they were among the most effective anti-submarine ships of the battle in the Atlantic. The design was gradually improved and this book uses plans of four selected ships to chart that development. These comprise: _Black Swan_ as built; _Flamingo_ as modified later; _Starling_, the single most successful U-boat hunter of the war, as in 1943; and _Amethyst_, as refitted after her clash with Chinese communists on the Yangtze in 1949.