Profile and plan views of the Russian battlecruiser Izmail. The design was probably developed by the Russian Shipbuilding Committee, led by Aleksander Krylov, and was based on the Gangut class battleships.
A few years before the outbreak of the First World War, the Russian Navy tried to rebuild its worn-out battle fleet. At that time, Russia was allied with Britain and France, with Germany being perceived as the major threat to this alliance. After having discussed the potential construction of new vessels with foreign shipyards, the navy decided to build them in Russia. The Russian Navy’s strategic plan included some unrealistic ambitions. It was envisaged that, between 1909 and 1930, Russia would deploy a powerful fleet in the Baltic that included twenty-four battleships and battlecruisers and twelve armoured cruisers. This naval build-up was part of two plans known as the ‘Great Programme’ and the ‘Small Programme’. The navy presented the Great Programme to the lower house of parliament, the Duma, and asked for 1.5 billion roubles to produce, initially, twelve battleships and four battlecruisers. The Duma opposed this huge expenditure but was overruled by the Imperial Council, parliament’s upper chamber, which, in July 1912, endorsed a so-called Little Programme. This provided 502 million roubles to build four battlecruisers, four armoured cruisers and several additional surface ships and submarines.
Naval developments in Europe obliged the Russian navy to focus on strengthening the Baltic and the Black Sea fleets especially. The four battlecruisers envisaged in the Little Programme were, in fact, expected to operate in the Baltic and their design had started at the time the Imperial Council endorsed the plan. The design was probably developed by the Russian Shipbuilding Committee, led by Aleksander Krylov, a well-known naval architect of the time, and was based on the Gangut class battleships. The initial requirements for the battlecruisers – named Borodino, Izmail, Kinburn and Navarin – called for 12in guns and a top speed of 28 knots. A number of private shipyards submitted preliminary bids but their costs were deemed too high and led to a reconsideration of the requirements. After a number of designs were produced, and influenced by information coming from Germany, the navy decided to increase the calibre of the main guns to 14in, although this resulted in a reduction in speed and some changes to the protection scheme. The initial idea to equip the vessels with superfiring turrets was abandoned in favour of a more traditional layout that took into account the disposition of the propulsion plant.
After several iterations, the Russian Admiralty eventually approved the final design and the construction contracts were awarded to the New Admiralty Shipyard (Izmail and Borodino) and the Baltic Yards (Navarin and Kinburn), both based in St. Petersburg. The Duma had allocated 45.5 million roubles for each ship but the change in the main battery calibre and other modifications caused the estimated cost to increase by seven million roubles per ship.
In principle, Russian battlecruiser design resembled a more German rather than British approach because protection was not neglected in favour of high speed. In fact, the Borodinos corresponded much more to battleships. However, some of the solutions chosen for both the main and secondary batteries would make them difficult to operate.
The Borodinos had a design displacement of 32,500 tons, which increased to 38,000 at full load. Their overall length and beam were, respectively 750ft and 100ft. Design draught at full load displacement was 33.5ft. The hull included a bow slightly shaped as a ram and a rounded stern. The hull’s forward section had short parallel sides that converged to form the bow, a strange configuration probably introduced to increase waterline area and stability in that section. Fore freeboard was 29ft 2in but decreased sharply to 20ft 6in amidships. The general hull arrangement was much influenced by the main battery layout, which comprised four centreline triple turrets including two placed amidships with a funnel between them. The gun layout allowed a twelve-gun broadside, with training of the two amidships turrets eased by the lack of deck structures. ‘A’ and ‘Y’ turrets had a 310° arc of fire, which decreased to about 280° for the amidships ones. However, only one turret could fire ahead or astern because training of the amidships turrets was constrained by the funnels and other deck fittings. Service boats were mostly located between ‘P’ and ‘Y’ turrets and were handled by two small derricks.
The fore hull section housed ten 5.1in single guns mounted in casemates which were placed on both the main and upper decks. Other 5.1in guns were casemated in the main deck and along the hull sides, a position that would render them very wet and hard to operate in bad weather. The disposition of the secondary battery was probably chosen to allow the magazines for the main and secondary guns to be placed close to each other. A short forecastle ran to the small superstructure, which was connected to the forward funnel by two short platforms. The superstructure supported the fore pole mast while the aft pole mast was placed behind the ‘Y’ turret.
The hull was divided into six decks, with a 4ft 2.2in double bottom running along its entire length. Twenty-five watertight bulkheads provided horizontal subdivision and a good level of compartmentalisation. Internally, the hull reflected the main battery layout because ‘Q’ turret’s magazine was placed between two groups of boiler rooms. The Borodinos would have twenty-five Yarrow large-tube boilers, working at 242 lb/sq.in., and placed in seven rooms. The three forward boiler rooms housed only oil-fired boilers while the others housed only coal-fired ones. Two engine rooms located between ‘P’ and ‘Y’ turrets housed four sets of Parsons turbines, each driving one shaft. A longitudinal bulkhead separated the engine rooms into four spaces. The HP turbines drove the outer shafts while the inner shafts were driven by LP turbines. Maximum designed power was 68,000shp, with a corresponding speed of 26.5 knots. Fuel capacity was about 3,800 tons, almost equally divided between coal and oil. The radius of action was 2,280 miles at 26.5 knots, a figure that was deemed sufficient for operations in the Baltic. Power generation was provided by six turbo-generators and two diesel generators, each rated at 320kW and thus giving a total output of 2,560kW. These were housed in four compartments on the platform deck, two forward and two aft of the machinery spaces. A power grid including DC and AC sections ensured a reliable distribution of electricity to all users. The Borodinos had two rudders in tandem and three Frahm anti-rolling tanks on each side.
The protection scheme was based on trials carried out on Chesma and included KC plates. Vertical protection included two belts. The main belt was 9.35in, ran from ‘A’ to ‘Y’ barbettes and was backed by 3in of wood to improve the connection between the armour and the hull structure. This belt extended vertically 16ft 5.4in above the waterline and 5ft 5in below. A 3in forward bulkhead and an 11.8in one aft closed the citadel; however, the thickness of the aft bulkhead decreased to 4in at the lower deck. The main belt decreased to 4.9in plates, backed by 2in of wood, forward and aft the ‘A’ and ‘Y’ barbettes. The upper belt was 3.9in, was 9ft 6in high, ran along the main deck and was closed at the ends by two 4in bulkheads. Behind the vertical armour, there was a 2in longitudinal splinter bulkhead between the main and lower decks. This bulkhead sloped down until it met the lower edge of the main belt and increased to 3in. 1in-4in plates protected the steering compartments and the extreme aft section of the hull. The hull’s forward end was 4.4in.
Horizontal protection was modest. The forecastle deck was only 0.35in before ‘A’ turret and increased to 1.4in around it. The main deck was mostly 1.47in, with some reinforcements around the barbettes. The lower and platform decks had about 0.75in. Underwater protection was limited to a 0.39in bulkhead behind the side upward extension of the double bottom. Funnel uptakes had 2in.
Barbettes were 11.8in in the upper part, decreased to 5.8in in the lower part and were shaped as truncated cones, thus lessening their protective purpose. Turrets had 11.8in faces, sides and rears; their roofs were 5.9in. Two 1in bulkheads separated each gun inside the turrets. The conning tower had 15.7in in the upper part, which reduced to 11.8in below the upper deck, and a 10in roof.
The main armament would consist of twelve Pattern 1913 14in/356mm 52-calibre guns, divided between the four electrically-powered triple turrets. Each turret weighed 1,368 tons. The gun’s design started in 1910 and it was first produced by the Obukhovski Steel Plant (OSZ) and Vickers to equip the Imperatritsa Mariya class battleships. However, OSZ was unable to produce enough guns to meet the projected schedule for the battleships and the Russian navy decided to install them in the Borodinos. Eventually, OSZ completed only one and, although Vickers delivered ten guns to Russia in May 1917, the Borodinos never had them installed. This gun had a rate of fire of three rounds per minute at -5/+15° of elevation. Maximum elevation was 25°, which corresponded to a range of 25,420yd with a 1,586lb AP shell, but the rate of fire was reduced. Ammunition outfit was eighty rounds per gun.
The secondary battery’s layout reflected the Russian navy’s view that torpedo attacks would mainly come from the forward quarters. This led to the installation of ten Pattern 1913 single casemated, 5.1in/130mm, 55 calibre guns in the hull forward section, abreast ‘A’ turret. Another two single casemated guns were placed abeam the superstructure and four others were placed, respectively, abeam ‘Q’ and ‘P’ turrets. The aft four casemated mounts were placed abeam the ‘Y’ turret. Vickers designed this gun as the 5.1in Mark A and, while OSZ produced it for other Russian warships, its production for the Borodinos was never completed. The designed rate of fire was 5-8 rounds per minute. Elevation would be limited to 30°; using AP or HE shells, the corresponding range was 20,000yd. Design ammunition outfit was 245 rounds per gun. Each main turret roof would have two 3in/75mm guns for training purposes and anti-aircraft defence would be provided by four 2.5in/64mm 38-calibre single guns placed on the upper deck, abreast the superstructure. The Borodinos would have six underwater Mod 1912 18in/450mm torpedo tubes, with eighteen weapons. The torpedo tubes were housed in pairs in three rooms, located respectively abeam the conning tower, ‘Q’ turret and ‘Y’ turret.
Fire-control equipment would include British, German and Russian components. ‘A’ and ‘Y’ turrets each had a 6-metre Zeiss rangefinder and another 5-metre Zeiss rangefinder was placed on the conning tower roof. A spotting top, probably equipped with a rangefinder, was located on the forward mast. Information from the rangefinders would feed an N K Geisler electro-mechanical fire-control computer housed in a transmitting station that was located on the platform deck. The Geisler system included a Russian-designed Eriksen range clock and a device to correct for the effects of erosion on the guns’ bores. The Borodinos had seven searchlights. A 36in searchlight was placed closely forward of ‘A’ turret. A pair of 43in searchlights was on a platform that partially surrounded the forward funnel and another, identical, pair was on a similar platform around the aft funnel. The last pair was on a low platform on the aft mast. Complement would include about 1,250 men and officers.
All four ships were laid down on 12 December 1913 but modifications to the protection scheme and serious delays in the fabrication of important items, such as the main turrets, caused their construction to slow. Izmail was launched first, on 22 June 1915, and was followed by Borodino and Kinburn on 31 July and 30 October respectively and Navarin on 9 November 1916. Political turmoil also heavily affected work in all sectors of the shipbuilding industry, including the outfitting of the Borodinos. At the time of the October 1917 Revolution, Izmail was about 60% complete but the turrets not would be available before 1919. By end of 1917, the new Soviet authorities decided to halt the construction of the Borodinos and their incomplete hulls lay up alongside for several years after the end of the war.
Plans to complete at least two or three ships were made, including some changes in the main armament and in the power generation and distribution system. However, civil war and the poor state of the Soviet economy hampered both current and potential plans. After the end of the civil war, Borodino, Kinburn and Navarin were sold to Germany and were scrapped in 1923 in, respectively, Bremen, Kiel and Hamburg. In May 1925, the Soviet Navy considered converting Izmail into an aircraft carrier, displacing 22,000 tons and with a capacity of fifty aircraft. This proposal was initially approved by the Soviet government, but it was reversed after the Red Army opposed allocating funds to naval programmes.
The Borodino class battlecruisers were comparable in size, protection and speed to contemporary British and German designs – and the 14in guns would have made them slightly superior to the latter. However, some serious design flaws, including the main battery’s layout, combined with the inherent weakness of domestic industry and tragic political events, prevented their realisation.