The King George V class - Fire Control Arrangements
(Not how the maths works - that's far too complicated!)
(1/17)
For the 14-inch guns the centrepiece of the Fire Control System was the Admiralty Fire Control Table (AFCT). The KGVs carried the Mark IX.
(Pictured is Belfast's, a Mk VI, which is smaller).
Each turret also contained an Admiralty Fire Control Box for local control.
(2/17)
The AFCT was buried deep within the ship, under armour, in the Transmitting Station.
The main armament was controlled via the AFCT from one of three locations:
- The forward Director Control Tower
- The aft Director Control Tower
- 'B' Turret
(3/17)
The Director Control Tower (DCT) combined the earlier Director Tower with control personnel. The idea was to avoid coordination problems by combining rangefinding, director and control personnel in one location.
(Shown is a cruiser's, but very similar)
(4/17)
The forward DCT was the principle fire control position. The position was unarmoured, being located high in the ship.
The aft DCT functioned as a back up to the forward director, in case of action damage, and also covered the arcs the forward couldn't see.
(5/17)
The aft DCT was also splinter protected, with 3" of Non Cemented armour plating.
In case both DCTs were out of action, the entire 14-inch battery could be controlled from 'B' turret.
(6/17)
The DCT was designed with a 15 foot (4.6m) rangefinder. In Duke of York, Anson and Howe, the forward DCT had this replaced by a 22 foot (6.7m) model before completion.
(7/17)
Ranges from the DCTs were supplemented from long-base rangefinders in each turret.
'A' and 'Y' turrets had 41 foot (12.5m) models. 'B' turret had a duplex 30 foot (9.1m) model. These could slew 5 degrees either way to allow for deflection.
(8/17)
Designed before radar, the class nonetheless entered service with a set for fire control. King George V entered service with a Type 284 set on her forward DCT. By the end of the war all ships had radar on both DCTs, mostly with the Type 274 which followed the Type 284.
(9/17)
The fire control system proved very successful, perhaps best shown by Duke of York's performance at the Battle of North Cape.
(10/17)
The 5.25-inch guns were controlled by 4 High Angle Director Towers (HADT), in a 'four cornered' arrangement.
Each nominally controlled two of the 5.25-inch turrets and covered that 'quarter'.
(11/17)
King George V and Prince of Wales had Mk IV HADTs. Duke of York, Anson and Howe had Mk V HADTs. Anson later had these replaced with Mk VI towers.
The differences were mostly layout and space - the later ones had better provision for radar, for example.
(12/17)
All four turrets on each side could be connected to either HADT for flexibility / redundency.
Each HADT also had it's own 'High Angle Control Position' (HACP) below armour - a 'transmitting station' for the secondary armament.
(12/17)
Because the 5.25-inch guns were dual purpose, each HACP contained two fire control computers. A High Angle Control System Mk IV* (HACS) for anti-air work and a Admiralty Fire Control Clock Mk VII* (AFCC) for anti-surface work. These were toggled by a simple switch.
(13/17)
The HADTs contained a 15 foot (4.6m) rangefinder, and carried radar from 1941 (generally Type 285, but Anson had these replaced by Type 275 in 1944-45).
(14/17)
As designed, each of the four Octuple Pom Poms had its own director. When the Pom Poms were increased to 6, the number of directors was increased as well, but the one controlling 'B' turret's pom pom was later removed. Ultimately there were 7 directors for the 8 mounts.
(15/17)
These Pom Pom mounts also gained radar - Type 272 - during the war for rangefinding.
Finally, the surviving ships had 2 Quad Bofors mounts, and therefore these had US Mk 51 directors fitted,
(16/17)
Overall, I believe this to be a thorough, successful and well thought out set of fire control arrangements.
Modernisation was proposed post-war but there wasn't the money for this and nothing was done before the ships entered reserve.
(17/17)
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A brief thread on the Revenge class battleships, because there seems to be some myths about them.
Often seen as a retrograde step after the Queen Elizabeths, this misunderstands their fleet role compared to the Queen Elizabeth class.
The Queen Elizabeths were a 'special' class. Intended to give the battle fleet its own organic fast division, they introduced some notable improvements - the 15in gun, being entirely oil fueled, and the increased speed of 25 knots.
The Revenges were more of a successor to the Iron Duke class, designed as battleline units. As originally laid down speed reverted to 21 knots with mixed coal and oil fuel. (Coal, of course, being readily available in the UK and not reliant on overseas supply).
One of my favourite photos of the battleship HMS Prince of Wales, late summer/early autumn of 1941.
This profile view offers a good opportunity to highlight some features of the class, so, a thread...
First, the main armament. 10 x 14-inch guns in a 4-2-4 arrangement. The turrets were called 'A', 'B' and 'Y'. 'B' turret was originally conceived as a Quad as well, but changed to a twin to enable more armour to be carried on a Treaty limited displacement.
The King George Vs often get criticised for "only" mounting 14in guns, but they had a very respectable weight of fire compared to contemporary European capital ships (which they were explicitly intended to counter). Hood and Renown included as comparative famous British ships.
@ransonwrites To be honest, there wasn't much capacity for accelerating the Lions.
In essence, for most of 1934-35 the Royal Navy expected its next capital ship to have 14" guns. This was because most countries had indicated a willingness to reduce the calibre limit - except the USA.
@ransonwrites However, by Sep 1935 it had become clear that Japan would not agree to a reduction unless the USA didn, and the USA had given no such indication. European nations were also building fast 15" gun ships.
The need for a fast capital ship meant the 16" gun was viewed unfavourably.
Battleship Guns - Is fewer larger guns or more smaller guns better?
A question that troubled many a ship designer.
A comparison of 14", 15" and 16" guns...
1/30
The advantages of the larger gun are clear - it has a bigger shell, with more ability to penetrate armour. It'll generally have a larger bursting charge inside it.
Thefore, your hits are more likely to do significant damage when they do hit.
2/30
However, some urged that the important factor was to hit in the first place, and that the significance depends on *where* that hit is, rather than the size of the shell.
In such circumstances, more smaller guns will have an advantage.
HMS Vanguard, Britain's last battleship. A brief overview.
1/25
Vanguard was the last British battleship built – the 59th in a line of big-gun warships going back to Dreadnought. She was a ship with quite an interesting origin. In the late 1930s the Royal Navy had embarked on an ambitious construction programme of capital ships.
2/25
However, more ships were wanted. One of the main bottlenecks was the production of gun turrets. There were four old 15-inch gun turrets in storage, removed from the ‘large light cruisers’ Glorious and Courageous when they were converted into aircraft carriers in the 1920s.
The superstructure of the battleship HMS King George V, January 1941.
There's a lot going in this photo, but what is everything for? And the 'Queen Anne's Mansion' superstructure is a distinctive feature, but what actually is inside it?
Well, starting from the top...
(1/18)
This is the sight for the UP Launcher on "B" turret. As designed it was meant to be No. 1 Pom Pom director for an Octuple Pom Pom on "B" turret, but such mounts were in short supply when the ship completed.
(2/18)
These are High Angle Control System Directors, Mk IV. They are designed to control the 5.25-inch guns against either air or sea targets. The bar sticking out is a 15 ft long rangefinder. No radar on these yet.