Invincible class battlecruiser

The Invincible class was the first type of true battlecruisers built anywhere in the world. They were the brainchild of Admiral Sir John (Jackie) Fisher, the man who had sponsered the construction of the world's first all big gun warship, HMS Dreadnought. He visualised a new breed of warship, somewhere between the armoured cruiser and battleship - it would have the armament of the latter, but the high speed of the former.

In early 1906, three ships were laid down to the final specifications of Admiral Fisher's vision - HMS Invincible, HMS Inflexible and HMS Indomitable. Each carried eight 12 inch guns in four twin turrets, with two mounted fore and aft and another two on the centreline port and starboard. These guns were equivalent to those mounted in the most modern battleships. However, the armour protection given to the ships was light - the armoured belt measured 6 inches amidships and 4 inches at the bow, with the deck armour in some places only 3/4 of an inch thick. This compared with an armoured belt of 11 inches on Dreadnought. But, it was Admiral Fisher's assertion that the ships' speed would be their protection. They were designed for 25 knots, but in the event, all three bettered 28 knots.

All three ships entered service in the first half of 1908. Initially, Invincible and Inflexible were assigned to the Home Fleet, while Indomitable took the Prince of Wales (later King George V) to the tercentennial celebrations in Canada, before also joining the Home Fleet.

In 1914, Invincible was based on the east coast of England as part of Admiral Beatty's force, while Inflexible and Indomitable, together with the newer HMS Indefatigable formed the nucleus of the Mediterranean Fleet. It was in the Mediterranean that the first significant naval action of the First World War took place, when the British pursued the German warships Goeben and Breslau. Invincible 's first action was as part of the battlecruiser force supporting the Heligoland operation.

In November 1914, the Battle of Coronel took place and saw the cruiser squadron of Rear Admiral Christopher Cradock destroyed by the German squadron commanded by Admiral Graf von Spee. In response, the Admiralty ordered that a squadron of ships be sent to destroy the Germans. This was led by Admiral Sir Doveton Sturdee in Invincible, accompanied by Inflexible and several other cruisers. The result of this was the Battle of the Falkland Islands which saw the British force sink all five German warships.

On 24th January 1915, a force of German battlecruisers entered the North Sea in the vicinity of the Dogger Bank. Here they were met in action by a larger force of British battlecruisers, which included Indomitable. This action saw the German cruiser Blucher. In the same year, Inflexible was included in the bombardment force against the Turkish shore defences in the Dardanelles, in which she sustained significant damage. Towards the end of the year, the British battlecruiser force was organised into three squadrons, with the 3rd BCS consisting of the three Invincible class ships under the command of Rear Admiral H.L.A. Hood in Invincible.

In May 1916, the 3rd Battlecruiser Squadron had been temporarily re-assigned to the Grand Fleet for gunnery practice, and was re-located to Scapa Flow. On the 30th May, the entire Grand Fleet, along with Admiral Beatty's battlecruisers, had been ordered to sea to prepare for an excursion by the German High Seas Fleet. The outcome of this was the epic Battle of Jutland. In order to support Beatty, Admiral Hood took his three battlecruisers ahead of the Grand Fleet. In engaging the Germans, all three ships sustained damage, before Invincible took hits from the German battlecruiser Derfflinger and battleship König, which penetrated the flimsy deck armour and exploded in the 'Q' turret magazine which caused explosions in the adjacent 'P' turret, and led to the ship blowing up and breaking in two, with the loss of 1020 of her crew.

The loss of three battlecruisers at Jutland (the others were Queen Mary and Indefatigable) led to the force being reorganised into two squadrons, with Inflexible and Indomitable in the 2nd BCS. However, after Jutland there was little significant naval activity, thanks to the Kaiser's order that his ships should not be allowed to go to sea unless assured of victory. The end of the war saw the end for many of the older vessels, not least the two remaining Invincible class ships. Both were sent to the Reserve Fleet in 1919, and were paid off in March 1920, before being sold for scrap in December 1922.