Castle-class patrol vessel

Castle-class patrol vessel was a class of British patrol vessels for the Royal Navy.

Design
The Castle class was intended as a series of six offshore patrol vessels for the Royal Navy, designed in response to criticism of the previous Island-class for insufficient speed, non-optimal sea keeping and lack of a flight deck for rescue helicopters.

In the event, only two ships were built, HMS Leeds Castle and HMS Dumbarton Castle. Both vessels were built by Hall Russell in Aberdeen. These had significant improvements over the Island class - they are 300 tonnes larger, more stable in heavy seas, 3 kn faster and are fitted with a large flight deck that is capable of supporting a Sea King. For brief periods, the ships can accommodate up to 120 troops.

Their primary mission was to serve with the Fishery Protection Squadron, protecting both the fishing fleets and the oil and gas fields of the North Sea. In addition, they can also serve as minelayers, and have detergent spraying facilities on board for dispersing oil slicks.

Operations
Since the Falklands War, one ship had been kept long term in the Falkland Islands as a guardship. Leeds Castle and Dumbarton Castle rotated the role on a three-yearly basis, although the ship's crew usually did a six month rotation.

Replacement
The Castle class has now been replaced by a unique vessel based on the River-class, HMS Clyde, and both vessels of the class are now decommissioned. Originally due to transfer to the Pakistani Maritime Security Agency in 2007, the deal fell through and both ships have now been sold to Bangladesh Navy.

Ships in class

 * HMS Leeds Castle (P258) (Commissioned August 1981)
 * HMS Dumbarton Castle (P265) (Commissioned March 1982)