HMS Audacious

1914

Lough Swilly mine, the Olympic stood by Location: off Tory Island, Lough Swilly, Ireland · Coordinates: 55.27°N 7.77°W · Casualties: 1 · Survivors: ~900 · Depth: 67 m · Cause: mine — Struck a contact mine laid by the German auxiliary cruiser SMS Berlin during gunnery exercises off Lough Swilly on 27 October 1914. Flooded in the engine rooms, fires crept toward the magazine over twelve hours. The liner RMS Olympic (sister of the Titanic) attempted a tow that parted; she finally exploded at 21:00. · Fate: upside down · divers visit · Type: super-dreadnought · King George V class · Tonnage: 25,830 tons · Crew: 900 · Flag: United Kingdom · Launched: 1912 Royal Navy super-dreadnought, commissioned less than a year when she struck a German mine off Lough Swilly, Ireland, on 27 October 1914. The fire crept toward her magazine over twelve hours; Cunard's Olympic, sister of the Titanic, tried to take her in tow in vain. The only casualty was a petty officer aboard HMS Liverpool hit by a fragment from the final magazine explosion. The Admiralty kept the news secret until after the 1918 Armistice for reasons of naval morale. The Vessel HMS Audacious was a British dreadnought battleship of the Royal Navy's King George V class, built at the Cammell Laird yard at Birkenhead between 1911 and 1913 and commissioned on 21 October 1913. She was 182 metres long, 25,420 tons displacement, and armed with ten 13.5-inch primary guns in five twin-gun turrets (three on the centreline forward and aft, two en echelon amidships), sixteen 4-inch secondary guns, and five 21-inch torpedo tubes. Her armour protection included a 305-millimetre main belt of Krupp cemented armour, 279-millimetre turret face armour, and 76-millimetre deck armour. She was, at her commissioning in October 1913, among the most modern capital ships in the Royal Navy. Her specific design represented the final pre-Queen Elizabeth class of British dreadnought battleships: 13.5-inch primary armament (superseded by 15-inch in the subsequent Queen Elizabeth class of 1913-1915), triple-shaft turbine propulsion, and the standardised British dreadnought internal subdivision arrangements. By October 1914, Audacious had been assigned to the 2nd Battle Squadron of the British Grand Fleet under Admiral Sir John Jellicoe, based at the Grand Fleet anchorage at Scapa Flow (and subsequently at the wartime anchorage at Loch Ewe following the 1914 German U-boat threat). Her operational role was forward-line capital ship service: continuous readiness to engage the German High Seas Fleet at North Sea battle-readiness. Her master on 27 October 1914 was Captain Cecil Francis The Disaster The initial mine explosion penetrated Audacious's outer hull plating and entered her port-side double-bottom spaces. The damage was substantial but not immediately catastrophic: the ship's port wing compartment flooded, her port engine-room began taking on water, and she developed a list of approximately 15 degrees to port. Captain Dampier's initial response was standard mine-damage control. The watertight compartments adjacent to the damaged area were sealed, the ship's pumps were activated, and the damaged engine-room was progressively abandoned as the flooding exceeded pump capacity. Audacious's speed was reduced from 18 knots to approximately 8 knots; she continued under her remaining starboard engines. The second phase of the disaster, and the specific mechanism by which the ship was ultimately lost, was the progressive failure of the ship's structural bulkheads under the continuous flooding load. The specific issue was the failure of the main longitudinal bulkhead between the port wing compartments and the port engine-room: the bulkhead had been compromised by the mine explosion's shock wave and was progressively cracking under the hydrostatic pressure of the floodwater. Over the subsequent 12 hours, Audacious's flooding extended progressively through the compromised longitudinal bulkhead into the port boiler rooms, the central magazine spaces, and eventually into the starboard compartments via cross-bulkhead failures. The ship's list increased from 15 degrees to 25 deg