Editing HMS Launceston Castle (section)

==Design==
The {{sclass2|Castle|corvette}}s were an improved and enlarged derivative of the earlier {{sclass2|Flower|corvette|1}}s, which was intended to be built by shipyards that could not build the larger and more capable [[frigate]]s. The greater length of the Castles gave made them better seaboats than the Flowers, which were not originally designed for ocean escort work. Large numbers (96 in total) were ordered in late 1942 and early 1943 from shipyards in the United Kingdom and Canada, but [[Allies of World War II|Allied]] successes in the [[Battle of the Atlantic]] meant that the requirement for escorts was reduced, and many ships (including all the Canadian ones) were cancelled.<ref name="fried p156">{{Harvnb|Friedman|2008|p=156}}</ref><ref name="brownp136">{{Harvnb|Brown|2012|p=136}}</ref>

The Castles were {{convert|252|ft|0|in|m}} [[length overall|long overall]], {{convert|234|ft|0|in|m}} [[waterline length|at the waterline]] and {{convert|225|ft|0|in|m}} [[length between perpendiculars|between perpendiculars]]. [[Beam (nautical)|Beam]] was {{convert|36|ft|6|in|m}} and [[Draft (ship)|draught]] was {{convert|13|ft|5|in|m}} aft at full load.<ref name="Fried p324">{{Harvnb|Friedman|2008|p=324}}</ref> [[Displacement (ship)|Displacement]] was about {{convert|1060|LT|t|lk=on}} standard and {{convert|1590|–|1630|LT|t}} full load.<ref name="conways22p63">{{Harvnb|Gardiner|Chesneau|1980|p=63}}</ref> Two [[Three-drum boiler#Admiralty boiler|Admiralty Three-drum water tube boilers]] fed steam to a [[Marine steam engine#Triple or multiple expansion|vertical triple expansion engine]] rated at {{convert|2750|ihp|kW}} which drove a single propeller shaft. This gave a speed of {{convert|16.5|kn|lk=in}}.<ref name="conways22p63"/> 480 tons of oil were carried, giving a range of {{convert|6200|nmi|lk=in}} at {{convert|15|kn}}.<ref name="ellp205">{{Harvnb|Elliott|1977|p=205}}</ref>

The ships had a main gun armament of a single [[QF 4 inch Mk XIX naval gun|QF 4-inch Mk XIX]] dual-purpose gun, backed up by two twin and two single [[Oerlikon 20 mm cannon]].<ref name="ellp205"/> Anti-submarine armament consisted of a single triple-barrelled [[Squid (weapon)|Squid]] anti-submarine mortar with 81 [[depth charge]]s backed up by two depth charge throwers and a single depth charge rail, with 15 depth charges carried. Type 272 or [[Type 277 radar|Type 277]] surface search radar was fitted, as was [[high-frequency direction finding]] (HF/DF) gear. The ships' [[sonar]] outfit was Type 145 and Type 147B.<ref name="atlanp126-7">{{Harvnb|Brown|2007|pp=126–127}}</ref>

The small size and slow speed of the ''Castle''s meant that they were considered obsolete post-war, and they underwent limited modifications, with armament changes limited to replacing the twin 20mm mounts with single [[Bofors 40 mm Automatic Gun L/60|40 mm Bofors mounts]].<ref>{{harvnb|Marriott|1983|pp=20–21}}</ref> ''Launceston Castle'' had been modified to this standard by 1953.<ref>{{harvnb|Blackman|1953|p=50}}</ref>