J3 battlecruiser
Class overview | |
---|---|
Name | J3 |
Operators | Royal Navy |
Preceded by | Admiral class |
Succeeded by | G3 class |
Planned | 5 |
Cancelled | 5 |
General characteristics | |
Type | Battlecruiser |
Displacement | about 43,100 long tons (43,800 t) |
Length | 860 ft (262.1 m) |
Beam | 106 ft (32.3 m) |
Draught | 32 ft (9.8 m) (at deep load ) |
Installed power | 151,000 shp (113,000 kW) |
Propulsion | 4 shafts, 4 geared steam turbine sets |
Speed | 33 knots (61 km/h; 38 mph) |
Armament |
|
Armour |
The J3 class battlecruiser was a design study conducted during the
Background
In 1916 the US had declared its intention to create a Navy "second to none"; Congress had authorized the building of a large number of battleships and battlecruisers. In response, the Japanese government also began a large programme of warship building (
The US plan had been delayed by the wartime need to build smaller vessels. Nevertheless, estimates by the Admiralty were that by the early 1920s the Royal Navy would be behind in ships.[2] By the beginning of 1920 the Americans had completed one battleship since the end of World War I and had five more building. Seven more were intended to be laid down in 1920–21, six of which were the very large and powerful South Dakota class, armed with twelve 16-inch guns.[3] The Japanese had finished one battleship since the end of the war and had three more under construction. To respond to this state of affairs, the Admiralty initially planned to build three battleships and one battlecruiser in the fiscal year 1921–22 and again in 1922–23, but this was changed to four battlecruisers to be built first, presumably to be followed by the same number of battleships the following year.[2]
The British did have access to German technology through ships such as the battleship
The first two design proposals, 'K2' and 'K3', had a general layout similar to Hood, but were armed with either eight or nine 18-inch guns, in four twin or three triple
The configuration was considered poorly armoured and a more compact design I3 - with machinery aft, magazines centrally disposed and the main armament forward - was drawn up by the DNC and presented in late 1920. A variation of I3, the G3 design, with reduced gun calibre and thinner armour over machinery, was tendered as a means to reduce weight and hence increase speed.[5]
General characteristics
The J3 battlecruisers were of very similar size to the Admiral class. They had an
Propulsion
The J3 battlecruiser design had four geared steam turbine sets, each driving one propeller shaft, and arranged in two engine rooms. The forward engine room held the two turbines for the wing shafts, while the aft engine room contained the turbine for the port and starboard inner shafts. The turbines were powered by 18 Yarrow[clarification needed] small-tube boilers divided between nine boiler rooms. They were designed to produce a total of 151,000 shaft horsepower (113,000 kW) at a working pressure of 200 psi (1,379 kPa) and temperature of 200 °C (392 °F) with superheat. Maximum speed would have been 34 knots (63 km/h; 39 mph).[6]
Armament
Housing the main armament in triple turrets was new to the Royal Navy, though British companies had been involved in the production of triple gun turret designs for other navies.
The J3 design mounted nine 15-inch 50-calibre guns in three triple hydraulically powered Mark I
An
Fire-control
The main guns of the J3 battlecruisers could be controlled from any of the three
Armour
The J3 was armoured similarly to the Hood, with bands of varying thickness. The armour was angled to up to 25 degrees on the belt, to increase relative thickness. One of the considerations that led to the cancellation of the J3 design was that the protection scheme did not use an "all or nothing" layout as later designs, such as the G3; this led to the J3 wasting tonnage on armour that would not have withstood incoming fire, a situation that the Admiralty found unacceptable.[13]
Notes
- ^ Brown, p. 134
- ^ a b c Campbell, Part 1, p. 4
- ^ Friedman, pp. 420, 446
- ^ Campbell, Part 2, p. 13
- ^ Friedman p211
- ^ Campbell, pt. 4, p. 44
- ^ Campbell, Part 1, p. 9
- ^ Campbell, Part 1, p. 7
- ^ Raven and Roberts, pp. 98, 100
- ^ "British 16"/45 (40.6 cm) Mark I". Navweaps.com. 7 January 2009. Retrieved 26 July 2010.
- ^ a b c d Campbell, Part 3, p. 42
- ^ "British 4.7"/43 (12 cm) QF Mark VII 4.7"/40 (12 cm) QF Mark VIII 4.7"/40 (12 cm) QF Mark X". Navweaps.com. 31 December 2006. Retrieved 26 July 2010.
- ^ Brown, p. 75
References
- Brown, David K. (2003). The Grand Fleet: Warship Design and Development 1906–1922 (reprint of the 1999 ed.). London: Caxton Editions. ISBN 1-84067-531-4.
- Campbell, N. J. M. (1977). "Washington's Cherry Trees, Part 1". Warship. I (1). London: Conway Maritime Press: 2–12. ISBN 0-87021-975-8.
- Campbell, N. J. M. (1977). "Washington's Cherry Trees, Part 2". Warship. I (2). London: Conway Maritime Press: 12–19. ISBN 0-87021-975-8.
- Campbell, N. J. M. (1977). "Washington's Cherry Trees, Part 4". Warship. I (4). London: Conway Maritime Press: 37–41. ISBN 0-87021-975-8.
- Friedman, Norman (1985). U.S. Battleships: An Illustrated Design History. Annapolis, MD: Naval Institute Press. ISBN 0-87021-715-1.
- Raven, Alan & Roberts, John (1976). British Battleships of World War Two: The Development and Technical History of the Royal Navy's Battleship and Battlecruisers from 1911 to 1946. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-817-4.