The County class were designed around the GWS1 Sea Slug beam riding anti-aircraft missile system. Sea Slug was a first generation surface to air missile intended to hit high-flying nuclear-armed bombers. As such it had a range of some 27 km with a ceiling of 17,000 m travelling at a speed of over 1,000 km/h. Everything about the Sea Slug was on a grand scale, from the missile itself (six meters long and weighing two tons) to its handling arrangements and electronics systems; even fitting a single system aboard a ship the size of the "Counties" was a challenge. The enormous missile was stowed horizontally in a large magazine that took up a great deal of internal space. On the last four ships, some of the missiles were stored partly disassembled in the forward end of the magazine to enable the complement of missiles to be increased. These missiles had their wings and fins reattached before being moved into the aft sections of the handling spaces and eventually loaded onto the large twin launcher for firing. The electronics required for the Sea Slug were the large Type 901 fire-control radar and the Type 965 air-search radar. These required a great deal of weight to be carried high up on the ship, further defining the design. Sea Slug could also be used in the surface to surface role, and was a highly effective system in its day.
Short range air-defence was provided by the Sea Cat anti-aircraft missile, which made the "Counties" the first Royal Navy warships to be armed with two different types of guided missile.
As constructed, the County-class ships were armed with a pair of twin 4.5in gun mountings. The second batch of four ships (Antrim, Fife, Glamorgan and Norfolk) were refitted in the mid 1970s - this saw their 'B' position turrets removed and replaced by four single MM38 Exocet launcher boxes. This made the County-class ships the only Royal Navy ships to be fitted with three separate types of guided missile. It also left the un-refitted ships as the last Royal Navy vessels to be able to fire a broadside from multiple main armament turrets. The last multi-turreted broadside was fired from London on her return from deployment in the West Indies in 1981 prior to handover to the Pakistani Navy.
Antrim and Glamorgan both served in the Falklands conflict; Antrim was the flagship of Operation Paraquet, the recovery of South Georgia in April 1982. Her helicopter, the Westland Wessex HAS.Mk3, nicknamed "Humphrey", was responsible for the remarkable rescue of 16 SAS men from Fortuna Glacier and the subsequent detection and disabling of the Argentinian submarine Santa Fe. Whilst at San Carlos Water, a 1,000 lb (450 kg) bomb hit Antrim, but did not explode. Glamorgan, after many days on the "gun line" bombarding Port Stanley airfield, suffered a land-based Exocet strike at the end of the conflict, which destroyed her aircraft hangar and the port Sea Cat mounting.
| County class destroyer | |
|---|---|
| Builders: | Cammell Laird Swan Hunter Vickers Armstrong |
| Operators: |  Royal Navy Chilean Navy Pakistan Navy |
| Preceded by: | Daring class |
| Succeeded by: | Type 82 |
| Subclasses: | Batch 1 Batch 2 |
| In commission: | 16 November 1962 - 22 September 2006 |
| Completed: | 8 |
| Cancelled: | 2 |
| Laid up: | Almirante Cochrane ex Antrim Capitán Prat ex Norfolk |
| Lost: | HMS Devonshire (as target) Almirante Latorre (accident) |
| General characteristics | |
| Displacement: | 6,200 tons |
| Length: | 518.25 ft (157.96 m) |
| Beam: | 54 ft (16 m) |
| Draught: | 21 ft (6.4 m) |
| Propulsion: | COSAG on 2 shafts; 2× Babcock & Wilcox boilers, geared steam turbines, 30,000 shp 4× Metrovick G6 gas turbines, 30,000 shp |
| Speed: | 30 knots |
| Range: | 3,500 nm |
| Complement: | 471 (33 officers, 438 ratings) |
| Armament: | 2× Fore-mounted twin-gunned turret with 4.5 inch (114 mm) guns Mark N6 (Batch 2's turret "B" was later replaced by 4× MM38 Exocet missile launchers) 2× mountings for Oerlikon 20 mm cannon 1× Aft-mounted Seaslug GWS.1 or GWS.2 SAM (24 missiles) 2× mountings (port & starboard) for Seacat GWS-22 SAM 2× triple-tube launchers for shipborne torpedoes |
| Aircraft carried: | 1× Wessex HAS Mk 3 helicopter |
| Aviation facilities: | Flight deck and enclosed hangar for embarking one helicopter |
