HMS Vanguard (1909) - Armament

Armament

The main armament consisted of ten 12-inch (305mm) Mark XI 50-calibre guns, grouped in pairs in five turrets. (see footnote). There was one turret ("A") turret on the forecastle on the centreline; one turret on the quarterdeck ("Y") and one between the after funnel and the after superstructure ("X"), also both on the centreline; and two wing turrets ("P" and "Q"), situated one on either beam just astern of the fore funnel. All turrets except "A" were on maindeck level. "A" and "Y" turrets had a field of fire of approximately 270 degrees over the bow and stern respectively. "X" had a field of approximately 100 degrees on either beam. Both "P" and "Q" had in theory a 180 degree field from right ahead to right astern; in practice firing at any angle less than 30 degrees from the keel line produced unacceptable blast damage to the ship's own superstructure. The Mark XI gun fired a shell weighing 850 pounds, and could fire two rounds per minute, although to allow for the spotting of shell fall one round per minute was more usual. Although ten guns were shipped the lack of any facility for cross-deck firing by "P" and "Q" turrets restricted the broadside to a maximum of eight.

The secondary armament at completion of the ship was twenty 4-inch (102mm) 50-calibre BL Mark VII guns in single mounts, distributed in the superstructure and on the roofs of "A" and "Y" turrets. The guns on "A" turret, in spite of being provided with a screen, proved to be badly affected by blast from the nearby 4-inch guns in the forward superstructure, and were removed before the outbreak of the First World War. Extra guns were placed in the forward superstructure, but when later in the war the arming of merchant ships to combat the submarine assault in the Atlantic assumed a high priority, small calibre guns were taken from this and other battleships. In 1917 Vanguard retained thirteen guns of this calibre.

Vanguard also shipped four 3-pounder saluting guns. In addition she had three 18-inch torpedo tubes, one on either beam and one firing astern. There is no record of torpedoes being fired in action from this ship.