Design HMS Canopus (1897)

right elevation, deck plan , hull section depicted in brassey s naval annual 1906

canopus , 5 sister ships designed service in east asia, new rising power japan beginning build powerful navy, though role made redundant anglo-japanese alliance of 1902. ships designed smaller, lighter , faster predecessors, majestic-class battleships. canopus 421 feet 6 inches (128.47 m) long overall, beam of 74 ft (23 m) , draft of 26 ft 2 in (7.98 m). displaced 13,150 tonnes (12,940 long tons) , 14,300 tonnes (14,100 long tons) full loaded. crew numbered 682 officers , enlisted men.

the canopus-class ships powered pair of 3-cylinder triple-expansion engines, steam provided twenty belleville boilers. first british battleships water-tube boilers, generated more power @ less expense in weight compared fire-tube boilers used in previous ships. new boilers led adoption of fore-and-aft funnels, rather side-by-side funnel arrangement used in many previous british battleships. canopus-class ships proved steamers, high speed battleships of time—18 knots (33 km/h; 21 mph) 13,500 indicated horsepower (10,100 kw)—a full 2 knots faster majestics.

canopus had 4 12-inch (305 mm) 35-calibre guns mounted in twin gun turrets fore , aft; these guns mounted in circular barbettes allowed all-around loading, although @ fixed elevation. ships mounted twelve 6-inch (152 mm) 40-calibre guns mounted in casemates, in addition ten 12-pounder guns , 6 3-pounder guns. customary battleships of period, equipped 4 18-inch (460 mm) torpedo tubes submerged in hull.

to save weight, canopus carried less armour majestics—6 inches (152 mm) in belt compared 9 in (229 mm)—although change harvey armour in majestics krupp armour in canopus meant loss in protection not great might have been, krupp armour having greater protective value @ given weight harvey equivalent. similarly, other armour used protect ship thinner; bulkheads on either end of belt 6 10 in (152 254 mm) thick. main battery turrets 10 in thick, atop 12 in (305 mm) barbettes, , casemate battery protected 6 in of krupp steel. conning tower had 12 in thick sides well. fitted 2 armoured decks, 1 , 2 in (25 , 51 mm) thick, respectively.