HMS Hurst Castle (K416) was one of 44 s built for the Royal Navy during World War II. Completed in June 1944, she began escorting convoys in August and was sunk by a German U-boat the following month. Design and description 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 at standard load and at deep load. They had an overall length of , a beam of and a deep draught of . 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 and gave a maximum speed of . The Castles carried enough fuel oil to give them a range of at . The ships' complement was 99 officers and ratings. The Castle-class ships were equipped with a single QF 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 Oerlikon light AA guns. 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. Construction and career Hurst Castle, the only ship of her name to serve in the Royal Navy, was ordered on 2 February 1943 from Caledon Shipbuilding & Engineering Company and was laid down at their shipyard in Dundee on 6 August. She was launched on 23 February 1944 and was completed on 9 June. The ship sailed to the anti-submarine training base in Tobermory, Mull, HMS Western Isles, for working up. Hurst Castle was assigned to Escort Group B3 on 3 July and escorted Convoy OS 85/KMS 59 from Britain to Gibraltar on 2 August. The group escorted Convoy SL 167/MKS 58 from Gibraltar to the UK later that month. On 30 August Hurst Castle and her sister ship departed Derry, Northern Ireland, to rendezvous with Force 33 the following day. After meeting up with the other ships, they were tasked to search for the