The Castle-class corvette was a stretched version of the preceding Flower class, enlarged to improve seakeeping and to accommodate modern weapons. The ships displaced 1010LT at standard load and 1510LT at deep load. They had an overall length of 252feet, a beam of 36feet and a deep draught of 14feet. They were powered by a pair of triple-expansion steam engines, each driving one propeller shaft using steam provided by two Admiralty three-drum boilers. The engines developed a total of 2880ihp and gave a maximum speed of 16.5kn. The Castles carried enough fuel oil to give them a range of 6500nmi at . The ships' complement was 99 officers and ratings.[1]
The Castle-class ships were equipped with a single QF 4adj=onNaNadj=on Mk XVI gun forward, but their primary weapon was their single three-barrel Squid anti-submarine mortar. This was backed up by one depth charge rail and two throwers for 15 depth charges. The ships were fitted with two twin and a pair of single mounts for 20mm Oerlikon light AA guns.[2] Provision was made for a further four single mounts if needed. They were equipped with Type 145Q and Type 147B ASDIC sets to detect submarines by reflections from sound waves beamed into the water. A Type 277 search radar and a HF/DF radio direction finder rounded out the Castles' sensor suite.[3]
Bamborough Castle was laid down by J. Lewis & Sons at their shipyard in Aberdeen on 1 July 1943 and launched on 11 January 1944. She was completed on 30 May and served as a convoy escort, sinking the German U-boat in the Barents Sea with depth charges on 9 December 1944. The ship was placed in reserve on 25 May 1945. Bamborough Castle was reactivated in January 1946 and assigned to the Fishery Protection Flotilla based at Plymouth before she returned to reserve in 1947.[4] The ship was sold for scrap in 1959 and arrived at Llanelli on 22 May to be broken up.[5]