HMS Vanguard (1909)

The eighth HMS Vanguard of the British Royal Navy was a St. Vincent-class battleship, an enhancement of the "dreadnought" design built by Vickers at Barrow-in-Furness. She was designed and built during the Anglo-German naval race and spent her life in the British Home Fleet.

At the outbreak of World War I, Vanguard joined the First Battle Squadron at Scapa Flow, and fought in the Battle of Jutland as part of the Fourth Battle Squadron. As one of twenty-four dreadnoughts in Jellicoe's Battle Fleet, she did not suffer any damage or casualties.

Just before midnight on 9 July 1917 at Scapa Flow, Vanguard suffered an explosion, probably caused by an unnoticed stokehold fire heating cordite stored against an adjacent bulkhead in one of the two magazines which served the amidships gun turrets 'P' and 'Q'. She sank almost instantly, killing an estimated 804 men; there were only two survivors. The site is now designated as a controlled site under the Protection of Military Remains Act. One of the casualties of the disaster was Captain Kyōsuke Eto, a military observer from the Imperial Japanese Navy, which was allied with the Royal Navy at the time through the Anglo-Japanese Alliance.

In terms of loss of life, the destruction of the Vanguard remains the most catastrophic accidental explosion in the history of the UK, and one of the worst accidental losses of the Royal Navy.

Origin
The naval estimates for 1907-1908, (the amount of naval spending being requested) presented to the House of Commons by the First Lord, included funding for the construction of two battleships of the dreadnought type, or for three if no acceptable understanding could be reached with the other major naval powers at the Hague Conference. In the event no such understanding could be arrived at, and the St. Vincent class, originally planned to contain two ships (HMS Collingwood and HMS St. Vincent) was expanded to include HMS Vanguard.

HMS Vanguard was ordered on 6 February 1908 from Vickers yard in Barrow. She was laid down on 2 April 1908 and launched on 22 February 1909. She began trials in November 1909, completed in February 1910 and on 1 March 1910 she commissioned at Devonport in the first division of the Home Fleet.

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, and 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.

Armour
The whole waterline was protected, to a variable extent. The main armour belt was ten inches thick, and ran from a point level with the forward end of "A" barbette to the after end of "Y". Armour two inches thick extended all the way from the belt to both ends of the ship. An upper belt of eight inches thickness extended above the whole length of the main belt. The after bulkhead, eight inches in thickness, ran across the ship between the after ends of the main belt. Forward there were two bulkheads; one five inches thick level with the forward end of "A" barbette, and one of four inches slightly less than halfway between this one and the stem. The strength of the decks varied in a complex fashion, dependent of the presence or absence of overlying structures. Counting from the top, the maindeck was of between 1.5 inches and 0.75 inches; the middle deck was 1.75 inches; and the lower deck was between 3 inches and 1.5 inches. The turret faces had eleven inches of armour; the barbette trunks had five to nine inches, being less where protection was already afforded by nearby structures. The conning tower had armour varying between eleven inches to eight inches, again according to the degree of protection afforded by nearby structures.

Machinery
Vanguard was powered by four Parsons direct drive turbines, driving four shafts. Steam was provided by eighteen Babcock and Wilcox large-tube boilers, with a working pressure of 235 pounds per square inch. The designed Shaft Horse Power (SHP) was 24,500, and the design maximum speed at this SHP was 21 knots. A full fuel load was 2,700 tons of coal and 850 tons of oil, which gave a radius of action of 6.900 nautical miles at ten knots

On trials she exceeded her design speed, delivering a speed of 22.1 knots from 25,800 SHP.

Career
Following her commissioning she remained with the Grand Fleet, taking part in periodic exercises. She was present at the Coronation Fleet review on 24 June 1910. She underwent a refit in 1911-12, leading otherwise an uneventful existence.

On 29 July, in common with much of the Grand Fleet, she moved to Scapa Flow, at that time the main base of the battle fleet in time of war. On 1 September 1914 at about 18:00 she opened fire on a target which was believed to be a submarine but which proved not to be.

In May 1916 she was transferred to the Fourth Battle Squadron (4BS), a move which affected her position in the chain of command but not her geographical location. On 31 May she sailed with the Grand Fleet, and was present at the Battle of Jutland. After the deployment of the battle fleet she lay in sixteenth place in the line. She took part in the action against the head of the German High Seas Fleet and against the German battlecruisers; it is not known if she scored any hits, and she herself received no hits. She returned with the fleet to Scapa Flow, and on 9 July 1917 spontaneously blew up.

Explosion
On the afternoon of 9 July 1917, the ship's crew had been exercising, practising the routine for abandoning ship. She anchored in the northern part of Scapa Flow at about 18.30. There is no record of anyone detecting anything amiss until the moment of the explosion at 23:20.

A court of inquiry heard accounts from many witnesses on nearby ships. They accepted the consensus that there had been a small explosion with a white glare between the foremast and "A" turret, followed after a brief interval by two much larger explosions. The Court decided, on the balance of the available evidence, that the main detonations were in either "P" magazine, "Q" magazine, or both. A great deal of debris thrown out by the explosion landed on nearby ships; a section of plating measuring five feet by six feet landed on board HMS Bellerophon (1907). It was matched with a sister ship, and was found to be from the central dynamo room, which reinforced the evidence suggesting that the explosion took place in the central part of the ship.

Although the explosion was obviously an explosion of the cordite charges in a main magazine, the reason for it was much less obvious. There were several theories. The inquiry found that some of the cordite on board, which had been temporarily offloaded in December 1916 and catalogued at that time, was past its stated safe life. The possibility of spontaneous detonation was raised, but could not be proved. It was also noted that a number of ship's boilers were still in use, and some watertight doors which should have been closed in war-time, were open as the ship was in port. It was suggested that this might have contributed to a dangerously high temperature in the magazines. The final conclusion of the board was that a fire started in a 4-inch magazine, perhaps when a raised temperature caused spontaneous ignition of cordite, spreading to one or the other main magazines which then exploded.