On 5 February, "Duchess" joined units of the Home Fleet on the Spring Training Cruise. The cruise included multi-national exercises in the Mediterranean, a port visit to Oran, and a joint Home-Mediterranean Fleets exercise. "Duchess" returned to Portsmouth on 23 March. On 29 April, the destroyer departed for Gibraltar to meet the royal yacht "Britannia", which was carrying Queen Elizabeth II on the final legs of her Commonwealth Tour. "Duchess" was part of the escort force until "Britannia" reached the Thames Estuary on 13 May. The destroyer then proceeded to Invergordon for Home Fleet exercises. On 19 June, "Duchess" and sister ship were detached for a three-week flag-showing cruise around the Baltic Sea. Port visits were made to Oslo, Copenhagen, and Stockholm before "Duchess" returned to Portsmouth. On 31 August, the ship was paid off and recommissioned. She was reassigned to the Mediterranean Fleet, and sailed on 10 September for Malta. On 15 October, "Duchess" was part of a demonstration of naval power for the Emperor of Ethiopia. The rest of the year was spent on exercises, including NATO exercise Novex 54, along with port visits to Elba with the cruiser in November. In early January 1955, "Jamaica" and "Duchess" made a formal visit to Algiers, which was then followed by more exercises. On 24 March, while moored at Naples, "Duchess" was rammed by the United States merchant ship SS "Excambion". Damage to the destroyer included punctured hull plating on the starboard bow, impact damage to the starboard stern plates where the collision forced them into the wharf, and damage to the superstructure. Temporary repairs were effected, and the destroyer was able to sail to the Malta Dockyard on 30 March. Repairs took most of April, and it was not until 22 May that the ship was deployed again, on a cruise to the eastern Mediterranean. "Duchess" visited Istanbul, Alexandria, and Cyprus before returning to Malta's Grand Harbour on 22 June. Two days later, with her Mediterranean deployment at an end, "Duchess" departed for Portsmouth via Gibraltar. On her 1 July arrival, the destroyer was docked for maintenance.