High Quality Content by WIKIPEDIA articles! HMS Dalrymple (K427/A302) was a Bay-class anti-aircraft frigate of the British Royal Navy, which served as a survey ship, mostly in the Persian Gulf, from 1948 until 1965. She was completed to deal with the large numbers of uncharted wrecks and mines around the British Isles as a result of World War II. For this purpose she was fitted for minesweeping. She was named for the pioneering Hydrographer of the Admiralty Alexander Dalrymple (1737-1808).