8 December, and was east of Jura the following day, having resumed surveys. She broke off surveying on 13 December and sailed south for Portsmouth, securing outboard of the on 16 December 1982, before granting Christmas leave to the majority of the ship's company. Despite the interruptions due to bad weather, of surveying were completed in the three weeks on task. She sailed Portsmouth five days into the New Year and arrived on the survey ground, off the west coast of Scotland, on 7 January 1983, but surveying proved difficult owing to rough weather; the survey area was about north of the aptly named Bloody Foreland in the northwest of Ireland. She was off Jura on 8 January and made passage through the Sound of Islay on 10 January. She broke off surveying on 13 January and set passage to the River Clyde, arriving alongside Greenock Pier a day later, sailing again for the survey ground on 17 January. She passed round the Mull of Kintyre to the Sound of Jura on 18 January and resumed surveys the next day. Very rough weather forced the ship to shelter behind the island of Inishtrahull on 20 January, so little progress had been made before she broke off from surveys and sailed for Belgium on 26 January. She was on passage through the Irish Sea the next day and arrived alongside in Antwerp on 31 January for a four-day visit. She arrived back in Portsmouth, her home port, on 5 February 1983 for a scheduled docking and repairs to defects. She moved into dry dock, and was docked down from 15 to 23 February, the dock being flooded up on 24 February. HMS Hydra returned to sea on Monday 25 April 1983, for a brief trials and shakedown cruise prior to a week's Safety Operational Sea Training (SOST) at the Portland Naval Base, from 17 to 25 May. On completion of SOST, specialist equipment and trials personnel were embarked from the Admiralty Underwater Weapons Establishment (AUWE), Portland, for a two-month oceanographic trials cruise, in the Rockall Trench area and off Bear Island (Norway). The prototype Depth Analysis System developed at the Admiralty Compass Observatory was installed on the bridge, and trials staff embarked to conduct a short trial while on passage to Scotland. Visits were made to Trondheim and Lorient before the ship returned to her new base port of Devonport at