Castle class corvette

British corvette HMS Alnwick Castle (K405) at sea on November 8th, 1944.

The Castle-class corvettes were an updated version of the much more numerous Flower-class corvettes of the Royal Navy, and started appearing during late 1943. They were equipped with RDF as well as ASDIC.

This design was prepared at the same time as the Loch-class frigates for builders who could not accommodate the longer frigate hull, and also to utilize any spare, short slip that was available. Although pre-fabricated construction was considered, it better suited the builders to stick with traditional building methods, to bring the class "on stream" as quickly as possible, without setting up an infrastructure for pre-fabricating.

The design was basically a larger Flower-class, and although only 35 feet longer, this was enough to greatly improve sea-keeping and accommodation levels. Armament was along improved Flower-class lines except that a 12 inch Squid mortar replaced the "Hedgehog" launcher, and there was provision for four extra 20mm AA - although these were rarely fitted. The armament was arranged as that of the Loch-class was, with the "Squid" replacing the 4" gun on the shelter deck, the 4"/45-caliber Mk.XVI DP gun being moved ahead of this, emphasizing the move from gun to "squid" as the main armament. A lattice mast abaft the bridge carried surface warning RDF and HF/DF gear.

Although the same machinery as the Flower-class was installed, there was no loss in speed due to longer keel and weight reduction measures.

Despite being a great improvement over the Flower-class, they couldn't match the new Frigates that were becoming available in large numbers, and in 1943, production was cut back to place all emphasis on frigates.

Unit Run

Royal Navy

• HMS Hadleigh Castle (K355)
• HMS Portchester Castle (K362)
• HMS Rushen Castle (K372)
• HMS Bere Castle (K373)
• HMS Shrewsbury Castle (K374) - transferred to Norway, renamed KNM Tønsberg Castle
• HMS Oswestry Castle (K375)
• HMS Pendennis Castle (K376)
• HMS Alton Castle (K377)
• HMS Guildford Castle (K378)
• HMS Carisbrooke Castle (K379)
• HMS Warkworth Castle (K380)
• HMS Flint Castle (K383) - transferred to Republic of China, renamed ROCS Shuai Zhen
• HMS Leeds Castle (K384)
• HMS Dudley Castle (K385)
• HMS Amberley Castle (K386)
• HMS Berkeley Castle (K387) - transferred to Regia Marina, renamed RM Staffetta
• HMS Dumbarton Castle (K388)
• HMS Knaresborough Castle (K389)
• HMS Calshot Castle (K390)
• HMS Peel Castle (K391)
• HMS Rhuddlan Castle (K392)
• HMS Tamworth Castle (K393)
• HMS Monmouth Castle (K394)
• HMS Thornbury Castle (K395)
• HMS Appleby Castle (K396)
• HMS Launceston Castle (K397)
• HMS Rising Castle (K398) - transferred to Uruguay, renamed ROU Montevideo
• HMS Tintagel Castle (K399)
• HMS Alnwick Castle (K405)
• HMS Bamborough Castle (K412)
• HMS Farnham Castle (K413)
• HMS Hurst Castle (K416)
• HMS Kenilworth Castle (K420)
• HMS Maiden Castle (K443)
• HMS Nunney Castle (K446) - transferred to Republic of China, renamed ROCS Chiu Chin
• HMS Norham Castle (K447)
• HMS Pevensey Castle (K449)
• HMS Pembroke Castle (K450) - transferred to Republic of China, renamed ROCS Ta Ching
• HMS Tonbridge Castle (K451)
• HMS Norwich Castle (K452)
• HMS Sherborne Castle (K453)
• HMS Walmer Castle (K460)
• HMS Wolvesey Castle (K461)
• HMS Totnes Castle (K491)
• HMS Dover Castle (K492)
• HMS Sandgate Castle (K493)
• HMS Hever Castle (K521) - transferred to Republic of China, renamed ROCS Kao An
• HMS Hedingham Castle (K529) - transferred to Republic of China, renamed ROCS Te An
• HMS Oakham Castle (K530)
• HMS Scarborough Castle (K536)
• HMS Barnard Castle (K594)
• HMS Allington Castle (K689)
• HMS Caistor Castle (K690)
• HMS Lancaster Castle (K691)
• HMS Oxford Castle (K692)
• HMS Morpeth Castle (K693)
• HMS Caldecot Castle (K694)
• HMS Rayleigh Castle (K695)
• HMS Denbigh Castle (K696)

Royal Canadian Navy

• HMCS St. Thomas (K488)
• HMCS Hespeler (K489)
• HMCS Kincardine (K490)
• HMCS Orangeville (K491)
• HMCS Leaside (K492)
• HMCS Bowmanville (K493)
• HMCS Arnprior (K494)
• HMCS Copper Cliff (K495)
• HMCS Tillsonburg (K496)
• HMCS Humberstone (K497)
• HMCS Petrolia (K498)
• HMCS Huntsville (K499)