SHIP CLASS: Devastation-class
SHIPS-IN-CLASS (2): HMS Devastation; HMS Thunderer
OPERATORS: United Kingdom
PROPULSION: 1871: Penn Trunk 2-cylinder engine with 8 x rectangular boilers driving 2 x Griffiths screws at 6,640 horsepower; Post-1890: Triple expansion, coal-fired cylindrical boilers.
Detailing the development and operational history of the HMS Devastation (1873) Predreadnought Ironclad Battleship.
Entry last updated on 8/14/2017.
Authored by JR Potts, AUS 173d AB. Content ©www.MilitaryFactory.com.
In the late 1870's, Sir Edward J. Reed (1830-1906), the British Admiralty's Director of Naval Construction (DNC), was developing a new "turret battleship" and came upon the problem of adapting full sailing rig to an iron ship that weighed 13,000 tons heavy. How could wind propel an iron ship with enough speed to overtake or evade other ironclad vessels? Reed offered a radical design, one never considered before, for a battleship without masts and sails to the Admiralty that was loyal to wind, canvas and wood of traditional masted ships. Royal Navy battleships and cruisers (as well as those of other period naval powers) designed and built during the mid-1880s were fitted with full sailing rigs on top of iron hulls powered by steam. This limited armament firing arcs and position while also added unnecessary weight. Despite the traditionally accepted methodology, naval times were changing. The vessel in question became HMS Devastation, the first ocean-going capital ship not to showcase sails in the world and the first to mount all of her armament over the hull as opposed to within it. The British Navy had changed history yet again.
HMS Devastation was laid down on November 12th, 1869, a radical "pre-dreadnought" ironclad turret-battleship. The vessel did retain a single mast early on though this installation without sails, the perch specifically reserved for lookouts and signaling ship-to-ship (or shore). However, the mast was ultimately removed in the 1891 makeover of the class. She had a 10 foot freeboard and her amidships superstructure was conventional in enclosing her smoke funnels and bridgeworks. Reed designed the Devastation to have a high superstructure and her ventilation tubes and funnels safely above the waves (unlike the famous USS Monitor with no freeboard at all, leading to her demise under 20-foot waves). As built, Devastation fielded had 4 x 12-inch muzzle-loading guns housed in twin turrets located fore and aft, protected by a 12-inch belt of wrought-iron armor. The lack of masts allowed the guns to come to bear both fore and aft, not just for broadsides as in previous sail-and-steam ironclads. To round out her offensive-minded armament package, below the waterline there was a ram for piercing the hulls of enemy vessels at ranges within the capabilities of the main guns - a throwback to the ancient way of war dating back to the days of the 50-oared Greek "penteconter" sailing galley.
The Devastation class had electrically-powered lighting and electrically-assisted ammunition lifts while protection was through compound armor. The two turrets each commanded a firing arc of 280 degrees, made possible only through the absence of masts. Her hull was largely of iron and her forward and aft decks were covered with teak planking. She was propelled, as built, by reliable Penn- 2 cylinder trunk steam engines - trunk engines being the standard propulsion choice on British warships of the period. A major reason for their selection was their inherently compact size, allowing them to be fitted into smaller capital ships. This, coupled with a low center of gravity, made for a more tactically-friendly profile. A major restriction of these engine types was their inherent expense in operation, requiring more coal to produce output than competing steam plants. Trunk engines had poor results when they used higher-pressure boilers and the 2-cycle types were abandoned in favor of "Triple Expansion engines" which featured into the vessel's 1890 refit.
The new Triple Expansion Engine (TEE) was a steam-based powerplant in which the steam was expanded across three stages in cylinders of increasing diameter to accommodate the increasing volume of the steam. This third cycle piston chamber meant the TEE produced 30% more steam or power than the older 2-cycle engines. TEEs offered improved efficiency and greater range and speed from the same amount of fuel used in the 2-cycle designs. The excellent performance of the TEE made it the new choice-standard for most naval powers, making it possible to design larger and more powerful battleships in turn.
The Devastation, when launched, made all the world's existing battleships obsolete and she proved the most powerful sea-going class for nearly 15 years running. When HMS Dreadnought was built in 1906, all battleships then in service - like the Devastation-class - became "pre-dreadnought" battleships resigned to second rate status - such was the impact of HMS Dreadnought when she, herself, appeared on the world stage. While Devastation had a number of advances in naval technology designed into her systems, her major drawback lay in her battery of 4 x 12-inch guns. During an 1879 refit, 2 x 14-inch torpedo launchers were added.
As built, the decision was to use older muzzle-loading 12-inch guns on Devastation. After each gun was fired, they had to be reeled completely inside of the turret housing while an autoloader and ram rod were used to, first, place the powder charge down the barrel followed by the shell shot. The gun was then repositioned through a port in the armored wall as normal, made ready to fire at the commander's charge. Each gun required its own port and a substantial crew to manage effectively. The time-consuming muzzle-loading process was the same as used on HMS Victory tall ship some 100 years prior. Each turret was 30 feet in diameter and faced with 14-inch thick armor while her decks were covered with 3-inch deck armor. Although the turrets were trained by steam power, the shell and powder lifts and the rammers were manually-operated. This required a complete crew of 22 personnel to work each turret, 10 men per gun plus one officer per team.
In 1890, the Royal Navy made the decision to change the muzzle-loading guns to breech-loading artillery types for its fleet of capital ships partly based on the data compiled by the Devastation's service record. In the 1890 refit, the Royal Navy installed BL 10-inch (254mm) breech-loading guns into the turrets that once housed the 12-inch systems. The new guns sported a muzzle velocity of 2,040 feet per second (622 m/s) and held a maximum range of 10,000 yards (9,100 m) firing an autoloaded 500 pound (226.8 kg) shell and powder chargers. The advantage of the newer breech-loading guns was the reduced time between loads (the gun not having to be retracted) while the system also required less crew to operate efficiently. Shells and charges were also loaded through the breech and not down the muzzle, no longer requiring cannons to be brought inside the ship for reloading. The breech worked by way of an interrupted screw, a mechanical device that locked the breech closed with a number of threads engraved to ensure any faulty, internally exploding ordnance be relatively contained within the gun - a protective measure for the crew and vessel. During the 1890 refit, the decision to add more armament was made was well: 6 x 6-pounder and 8 x 3-pounder "rapid-fire" guns were positioned about the superstructure with the greatest firing degree arc as possible.
Despite a career spanning 37 years on the water, HMS Devastation never fired a shot in anger. Her primary mission prior to the 1890 refit was on assignment between the Home Fleet and on guard at the British base at Gibraltar for 20 years. After the 1890 refit, Devastation joined the Reserve Fleet out of Scotland, stationed to protect the Queen when she was in residence. Devastation was unceremoniously sold for scrap in 1906 and was officially broken up in May 1908.
Two vessels ultimately made up the Devastation-class: HMS Devastation served as the lead ship while HMS Thunderer (1872) became her sister. Thunderer was herself decommissioned in 1909 and sold for scrap the following July. Such ended the reign of the Devastation-class in service to the Royal Navy.