Armament
The main armament was ten 13.5 inch (343 mm) 45-calibre Mark V guns, disposed in five double turrets all positioned on the centre-line of the ship. "A" turret was positioned on the forecastle deck, and had an uninterrupted arc of fire over the deck of some 300 degrees. "B" turret was placed immediately aft of "A", one deck higher. In theory the arc of fire of "B" turret was also 300 degrees; in practice, because of the insistence by the Admiralty of the retention of sighting hoods in turret roofs, firing over "A" turret caused intolerable blast effects in "A" turret, limiting "B" therefore to firing on broadside arcs only. "Q" turret, positioned between the after funnel and the after superstructure and one deck level lower than "A", had an arc of fire of 120 degrees on either beam, with no possibility of fire either ahead or astern. "X" turret was at the same deck level as "A" turret; positioned on the quarterdeck and superfiring over "Y" turret, it possessed a theoretical arc of fire of 300 degrees over the stern, but in practice suffered from the same limitation as did "B" turret in terms of firing over the lower turret. "Y" turret was placed on the quarterdeck at the same height as "Q" turret, and enjoyed an uninterrupted arc of fire over the stern of 300 degrees. Maximum ammunition stowage was one hundred rounds per gun.
Sixteen four-inch (102 mm) 50-calibre Mark VII breech-loading guns were shipped as secondary armament. They were disposed symmetrically, eight being in the forward superstructure with fields of fire forward and on the beam, and eight being in the after superstructure and firing on the beam and aft. The number of guns was reduced to thirteen during the war, and a 4-inch anti-aircraft gun was installed on the quarterdeck.
Four 3-pounder saluting guns were carried high in the superstructure.
There were three 21-inch (533 mm) underwater torpedo tubes; one on each beam and one discharging astern. A total of twenty torpedoes was carried.
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