County-class cruiser

	Australia in 1937
Class overview
Name	County class
Operators	Royal Navy; Royal Australian Navy;
Preceded by	Hawkins class
Succeeded by	York class
Subclasses	Kent, London, Norfolk
In commission	1928–1959
Planned	16
Completed	13
Cancelled	3
Lost	3
Retired	10
General characteristics Kent class[page needed]
Type	Heavy cruiser
Displacement	10,400 tons average standard; 14,150 tons average full load;
Length	590 ft (180 m) p/p; 630 ft (190 m) (o/a);
Beam	68 ft (21 m) across bulges
Draught	17.25 ft (5.26 m) standard; 21.5 ft (6.6 m) full load;
Propulsion	8 × Admiralty three-drum boilers, Parsons (Brown-Curtis in Berwick) geared steam turbines on 4 shafts, 80,000 shp (60,000 kW)
Speed	31.5 knots (58.3 km/h; 36.2 mph)
Range	8,000 nautical miles (15,000 km; 9,200 mi) at 10 knots (19 km/h; 12 mph); 2,300 nautical miles (4,300 km; 2,600 mi) at 30 knots (56 km/h; 35 mph);
Complement	685 standard, 710 as flagship, 784 during wartime
Armament	8 × BL 8-inch (203 mm L/50) Mk.VIII guns in twin mounts Mk.I; 4 × QF 4-inch (102 mm) L/45 Mk.V guns in single mounts HA Mk.III; 8 × QF 2-pounder (40 mm) L/39 Mk.VIII guns in quad mounts HA Mk.VII (from 1925–); except Berwick; 16 in oct mounts Mk.VIII; 8 × 0.5-inch (12.7 mm L/50) Mk.III machine guns in quad mounts Mk.I (from 1924–); 8 × 21-inch (533 mm) torpedoes in quad mounts (removed from 1935–);
Armour	Main belt:; 4.5-inch (114 mm) with 1-inch (25 mm) closing bulkheads (Berwick, Cumberland, Suffolk, Kent & Cornwall only, from 1935–); Lower deck:; 1.25-inch (32 mm) over machinery; 1.5-inch (38 mm) over steering gear; Main box citadels:; 1–4-inch (25–102 mm) sides; 1-to-2.5-inch (25 to 64 mm) crowns; Turrets:; 1-inch (25 mm) faces, sides, rears, crowns & barbettes;
General characteristics London class
Displacement	9,840 tons standard average; 13,315 tons full load;
Length	595 ft (181 m) p/p; 632 ft 9 in (192.86 m) o/a;
Beam	66 ft (20 m)
Draught	17 ft (5.2 m) standard; 21 ft 6 in (6.55 m);
Speed	32.25 knots (59.73 km/h; 37.11 mph)
Complement	700 standard, 852 during war
Armament	8 × BL 8-inch (203 mm) L/50 Mk.VIII guns in twin mounts Mk.I*; 4–8 × QF 4-inch (102 mm) L/45 Mk.V guns in single mounts HA Mk.III; 4 × QF 2-pounder (40 mm) L/39 Mk.II guns in single mounts HA Mk.I; 8 × 0.5-inch (12.7 mm) L/50 Mk.III machine guns in quad mounts Mk.I; 8 × 21-inch (533 mm) torpedoes in quad mounts;
Armour	Main belt:; 3.5-inch (89 mm) with 1-inch (25 mm) closing bulkheads (London only, from 1938–);
Notes	Other characteristics as per Kent
General characteristics Norfolk class
Displacement	10,400 tons standard; 13,775 tons full load;
Length	595 ft 1 in (181.38 m) p/p; 632 ft 9 in (192.86 m) o/a;
Beam	66 ft (20 m)
Draught	18 ft (5.5 m) standard; 21 ft 6 in (6.55 m);
Complement	710 standard, 819 during wartime
Armament	8 × BL 8-inch (203 mm L/50) Mk.VIII guns in twin mounts Mk.II; 8 × QF 4-inch (102 mm L/45) Mk.XVI guns in twin mounts HA/LA Mk.XIX (from 1937–); 16 × QF 2-pounder (40 mm L/39) Mk.VIII guns in oct mounts HA Mk.VIII;
Notes	Other characteristics as per London

The County class was a class of heavy cruisers built for the Royal Navy in the years between the First and Second World Wars. They were the first post-war cruisers constructed for the Royal Navy and were designed within the limits of the Washington Naval Treaty of 1922. Such ships, with a limit of 10,000 tons standard displacement and 8-inch calibre main guns may be referred to as "treaty cruisers" (the term "heavy cruiser" was not defined until the London Naval Treaty of 1930^[1]^{[page needed]}).

The thirteen Counties were built in the Kent, London and Norfolk sub-classes. They were the only 10,000-ton 8-inch gun, or "A", cruisers that the Royal Navy built. The Counties are remembered for their distinctive three-funnel layout and service in all the major naval theatres of the Second World War.

To extract more ships from the treaty limits, the navy planned to construct 8,250-ton "B" ships, six of which could be built in place of five Counties. The extra ship that this afforded was an attractive proposition for a navy that had the immense peacetime commitments of empire.^[1]^{[page needed]}^[2] Peacetime economies and politics intervened and only two B-type cruisers were built, an 8-inch gun modified County design: the York class.

In 1929, the mean cost of each "A" ship was estimated to be £2,180,000, whilst the mean cost of each "B" ship was estimated to be £1,800,000.^[3]

^ ^a ^b ^c Lenton
^ Marriot (2005) c. 3, para. 23
^ Cuthbert Headlam (20 February 1922). "Cruiser Construction (Cost)". Parliamentary Debates (Hansard). Vol. 225. Parliament of the United Kingdom: House of Commons. col. 1104. Retrieved 24 May 2016.

[lenton-1] Lenton

[2] Marriot (2005) c. 3, para. 23

[3] Cuthbert Headlam (20 February 1922). "Cruiser Construction (Cost)". Parliamentary Debates (Hansard). Vol. 225. Parliament of the United Kingdom: House of Commons. col. 1104. Retrieved 24 May 2016.

[1]

[2]

[3]

Class overview
Australia in 1937
Name	County class
Operators	Royal Navy Royal Australian Navy
Preceded by	Hawkins class
Succeeded by	York class
Subclasses	Kent, London, Norfolk
In commission	1928–1959
Planned	16
Completed	13
Cancelled	3
Lost	3
Retired	10
General characteristics Kent class^[1]^{[page needed]}
Type	Heavy cruiser
Displacement	10,400 tons average standard 14,150 tons average full load
Length	590 ft (180 m) p/p 630 ft (190 m) (o/a)
Beam	68 ft (21 m) across bulges
Draught	17.25 ft (5.26 m) standard 21.5 ft (6.6 m) full load
Propulsion	8 × Admiralty three-drum boilers, Parsons (Brown-Curtis in Berwick) geared steam turbines on 4 shafts, 80,000 shp (60,000 kW)
Speed	31.5 knots (58.3 km/h; 36.2 mph)
Range	8,000 nautical miles (15,000 km; 9,200 mi) at 10 knots (19 km/h; 12 mph) 2,300 nautical miles (4,300 km; 2,600 mi) at 30 knots (56 km/h; 35 mph)
Complement	685 standard, 710 as flagship, 784 during wartime
Armament	8 × BL 8-inch (203 mm L/50) Mk.VIII guns in twin mounts Mk.I 4 × QF 4-inch (102 mm) L/45 Mk.V guns in single mounts HA Mk.III 8 × QF 2-pounder (40 mm) L/39 Mk.VIII guns in quad mounts HA Mk.VII (from 1925–) except Berwick; 16 in oct mounts Mk.VIII 8 × 0.5-inch (12.7 mm L/50) Mk.III machine guns in quad mounts Mk.I (from 1924–) 8 × 21-inch (533 mm) torpedoes in quad mounts (removed from 1935–)
Armour	Main belt: 4.5-inch (114 mm) with 1-inch (25 mm) closing bulkheads (Berwick, Cumberland, Suffolk, Kent & Cornwall only, from 1935–) Lower deck: 1.25-inch (32 mm) over machinery 1.5-inch (38 mm) over steering gear Main box citadels: 1–4-inch (25–102 mm) sides 1-to-2.5-inch (25 to 64 mm) crowns Turrets: 1-inch (25 mm) faces, sides, rears, crowns & barbettes
General characteristics London class
Displacement	9,840 tons standard average 13,315 tons full load
Length	595 ft (181 m) p/p 632 ft 9 in (192.86 m) o/a
Beam	66 ft (20 m)
Draught	17 ft (5.2 m) standard 21 ft 6 in (6.55 m)
Speed	32.25 knots (59.73 km/h; 37.11 mph)
Complement	700 standard, 852 during war
Armament	8 × BL 8-inch (203 mm) L/50 Mk.VIII guns in twin mounts Mk.I* 4–8 × QF 4-inch (102 mm) L/45 Mk.V guns in single mounts HA Mk.III 4 × QF 2-pounder (40 mm) L/39 Mk.II guns in single mounts HA Mk.I 8 × 0.5-inch (12.7 mm) L/50 Mk.III machine guns in quad mounts Mk.I 8 × 21-inch (533 mm) torpedoes in quad mounts
Armour	Main belt: 3.5-inch (89 mm) with 1-inch (25 mm) closing bulkheads (London only, from 1938–)
Notes	Other characteristics as per Kent
General characteristics Norfolk class
Displacement	10,400 tons standard 13,775 tons full load
Length	595 ft 1 in (181.38 m) p/p 632 ft 9 in (192.86 m) o/a
Beam	66 ft (20 m)
Draught	18 ft (5.5 m) standard 21 ft 6 in (6.55 m)
Complement	710 standard, 819 during wartime
Armament	8 × BL 8-inch (203 mm L/50) Mk.VIII guns in twin mounts Mk.II 8 × QF 4-inch (102 mm L/45) Mk.XVI guns in twin mounts HA/LA Mk.XIX (from 1937–) 16 × QF 2-pounder (40 mm L/39) Mk.VIII guns in oct mounts HA Mk.VIII
Notes	Other characteristics as per London