HMS Royal Oak (08) - Construction

Construction

The Revenge class to which Royal Oak belonged was ordered in the 1913–14 Estimates to be a cheaper—but smaller and slower—coal-fired version of the earlier oil-fired Queen Elizabeth-class super-dreadnoughts. The design, seemingly a technological step backwards, was partly a response to fears that a dependence upon fuel oil—all of which had to be imported—could leave the class crippled in the event of a successful maritime blockade. High-quality coal, on the other hand, was in plentiful supply, and homeland supplies could be guaranteed. Furthermore, in contrast to the "Fast Squadron" Queen Elizabeths, the Revenge class were intended to be the heaviest-gunned vessels in the line of battle proper. Royal Oak and her sisters were the first major vessels for the Royal Navy whose design was supervised by the newly appointed Director of Naval Construction, Sir Eustace Tennyson-D'Eyncourt.

Royal Oak was laid down at Devonport Dockyard on 15 January 1914, the fourth of her class. Concerned over the performance limitations of coal, and having secured new oil supplies with a contract agreed with the Anglo-Persian Oil Company, First Sea Lord Jackie Fisher rescinded the decision on coal in October 1914. Still under construction, Royal Oak was redesigned to employ eighteen oil-fired Yarrow boilers supplying four Parsons reaction steam turbines, each directly driving a single 9.5-foot (2.9 m) three-bladed screw. The battleship was launched on 17 November, and after fitting-out, was commissioned on 1 May 1916 at a final cost of £2,468,269. Named after the oak tree in which Charles II hid following his defeat at the 1651 Battle of Worcester, she was the eighth Royal Navy vessel to bear the name Royal Oak, replacing a pre-dreadnought scrapped in 1914. While building she was temporarily assigned the pennant number 67.

Royal Oak was refitted between 1922 and 1924, when her anti-aircraft defences were upgraded by replacing the original QF 3-inch (76 mm) 20 cwt AA guns with QF 4-inch (100 mm) high-angle mounts. Fire-control systems and rangefinders for main and secondary batteries were modernised, and underwater protection improved by 'bulging' the ship. The watertight chambers, attached to either side of the hull, were designed to reduce the effect of torpedo blasts and improve stability, but at the same time widened the ship's beam by over 13 feet (4 m).

A brief refit in early 1927 saw the addition of two more 4-inch (100 mm) high-angle AA guns and the removal of the two 6-inch (150 mm) guns from the shelter deck. The ship received a final refit between 1934 and 1936, when her deck armour was increased to 5 inches (12.7 cm) over the magazines and to 3.5 inches (8.9 cm) over the engine rooms. In addition to a general modernisation of the ship's systems, a catapult for a spotter float plane was installed above X–turret, and anti-aircraft defences were strengthened by doubling up each of the 4-inch (100 mm) AA guns and adding a pair of octuple Mark VIII pompom guns to sponsons abreast the funnel. The mainmast was reconstructed as a tripod to support the weight of a radio-direction finding office and a second High-angle Control Station. The extra armour and equipment made Royal Oak one of the best equipped of the Revenge class, but the additional weight caused her to sit lower in the water, lowering her top speed by several knots.