[1] Barnaby's final submission was inspired by the four French Terrible-class ironclads laid down in 1877–1878 and was a return to the configuration of Devastation with the primary armament positioned fore and aft of the central superstructure, but with the breech-loading main armament mounted in barbettes, as per the French ships,[2][3] which allowed them to be sited 10 feet (3.0 m) further above the waterline than Devastation's guns.

[4] The Board modified Barnaby's design by adding 25 feet (7.6 m) of length and 2,000 indicated horsepower (1,500 kW) to guarantee a speed of 15 knots (28 km/h; 17 mph) at deep load.

[5] Barnaby was severely criticised, particularly by Sir Edward Reed, himself a former Chief Constructor of the Royal Navy, because Collingwood's waterline armour belt was concentrated amidships and did not extend to the ends of the ship.

Reed believed that this weakness meant that the ship could be sunk from the consequent uninhibited flooding if her unarmoured ends were riddled by shellfire and open to the sea.

Furthermore, he heavily subdivided the hull to limit the amount of water that could enter through any one hit and placed coal bunkers above the armoured deck to absorb the fragments from exploding shells.

Unbeknownst to his critics, Collingwood was tested in 1884 with her ends and the large spaces in her hold ballasted with water and her draught only increased by 17.5 inches (440 mm) and she lost a minor amount of speed.

She was the first British ironclad to be equipped with forced draught and the ship only reached a speed of 16.84 knots (31.19 km/h; 19.38 mph) from 9,573 ihp (7,139 kW) while using it during her sea trials because her engines were incapable of handling the additional steam.

[8] Collingwood carried a maximum of 1,200 long tons (1,219 t) of coal that gave her a range of 8,500 nautical miles (15,700 km; 9,800 mi) at a speed of 10 knots (19 km/h; 12 mph).

[11] The secondary armament of Collingwood consisted of six 26-calibre BL 6-inch (152 mm) Mk IV guns on single mounts positioned on the upper deck amidships, three on each broadside.

The ship was commissioned at Portsmouth on 1 July 1887 for Queen Victoria's Golden Jubilee Fleet review and was paid off into reserve in August.

[17] Collingwood was recommissioned for the annual summer manoeuvres for the next two years, before she was assigned to the Mediterranean Fleet, where she served from November 1889 until March 1897, with a refit in Malta in 1896.

[19] She took part in the fleet review held at Spithead on 16 August 1902 for the coronation of King Edward VII,[20] and was back in Ireland later that month when she received the Japanese cruisers Asama and Takasago to Cork.