The two ships were designed to be improved versions of the and classes, having a greater displacement to allow for improved protection. However, they sacrificed a full armoured belt for greater thickness amidships in a partial belt.
As originally designed, Trafalgar was to have displaced 11,940 tons, and carried a secondary armament of ten guns of 5inches calibre, disposed in the broadside battery. Changes made during construction however, led to an increase in displacement to 12,590 tons; this led to the ships draught being increased by 12inches from the initial design, and 18inches with full bunkers. This in turn led to the main belt being immersed to a deeper level than had been intended, with a potential decrease in defensive effect in combat.
In October 1896 the secondary battery of 4.7inches guns was replaced by a more powerful battery of six 6inches quick firers.
The main artillery, while situated at a militarily effective height of 14feet above sea level, were only 42inches above the deck. It was thought possible that firing along the keel line might cause structural damage; tests requested by the Chief Constructor, however, showed the potential damage to be minimal.
As compared to, Trafalgars under-water hull form was finer, with a larger rudder. Together with the reduced freeboard as compared to earlier ships, this had a significantly adverse effect on her handling; as she spent her active service in relatively calm water in the Mediterranean, however, this defect was of minimal importance.
Trafalgar was completed, except for her main armament, in only three years and three months. The delay in the production of her guns meant that she was not commissioned, as second flagship Mediterranean Fleet until 2 April 1890. She served in this position until October 1897, when she paid off at Portsmouth. She was recommissioned, and stayed there as guardship until August 1902, taking part in the fleet review held at Spithead on 16 August 1902 for the coronation of King Edward VII.[1] Captain George Anson Primrose was appointed in command in December 1899. She remained thereafter in reserve until 1907, when she went to Sheerness to serve as a drill ship for crews of turrets and of submerged torpedo tubes. In April 1909 she reverted to active service with the fourth division of the Home Fleet, based at the Nore. She was sold on 9 March 1911.