Initially, all Seacat installations used a 4-round, trainable launcher, but a 3-round, launcher was later developed. Both launchers were manually reloaded and carried an antenna for the radio command link. All that was required to fit the system to a ship was the installation of a launcher, the provision of a missile handling room and a suitable guidance system. Seacat was used by
NATO and
Commonwealth navies that purchased British equipment and was exported worldwide. It has also been integrated with a variety of alternative guidance systems, the most common being Dutch
HSA systems. The four systems used by the Royal Navy are described below.
GWS-20 Hilda (
Tigercat) missiles on launcher This - "Guided Weapon System 20" - was the initial system, which was intended to replace the twin 40 mm Bofors Mark V gun and its associated fire-control systems. The original director was based on the Simple Tachymetric Director (STD) and was entirely visual in operation. The target was acquired visually with the missile being guided, via a radio link, by the operator inputting commands on a joystick. Flares on the missile's tail fins aided identifying the missile. 's GWS-20 was trialled on board HMS
Decoy, a destroyer, in 1961; it was subsequently removed. It was carried in active service by the landing ships, the
Type 12M (Rothesay-class) and
Type 12I (Leander-class) frigates, the
Type 61 (Salisbury-class) air defence frigates
HMS Lincoln and
HMS Salisbury, and the first group of s.
HMS Kent and
HMS London updated to GWS22 in the early 1970s. It was originally intended that all destroyers should receive GWS20, and the class were prepared accordingly. In the event only and
HMS Caprice received it, in 1966 refits. GWS-20 saw active service in the
Falklands War on board the
Fearless class and the
Rothesay frigates and , which retained the GWS-20 director when upgraded to GWS-22.
GWS-21 GWS-21 was the Seacat system associated with a modified Close Range Blind Fire analogue fire control director (CRBFD) with Type 262 radar. This offered manual radar-assisted (
Dark Fire) tracking and guidance modes as well as 'eyeball' visual modes. It was carried as the design anti-aircraft weapon of the
Type 81 (Tribal-class) frigate, the four AD conversions, on the first four County-class destroyers,
HMNZS Otago and
HMNZS Taranaki, and the carrier
HMS Eagle. It was last used after sale to the Indonesian Navy and refit by
Vosper Thornycroft in 1984 of, the Type 81s
Tartar,
Ashanti and
Gurkha.
GWS-22 GWS-22 was the Seacat system associated with the full MRS-3 fire control director with Type 904 radar and was the first ACLOS-capable (Automatic, Command Line-Of-Sight) Seacat. It was fitted to most of the
Leander,
Rothesay and County-class escorts as they were refitted and modified in the 1970s, as well as the
aircraft carrier . It could operate in automatic radar-guided (
Blindfire), manual radar-guided, manual CCTV-guided or, in an emergency, 'eyeball' guided modes. It saw active service in the Falklands onboard all these classes.
GWS-24 The final Royal Navy Seacat variant, this used the Italian Alenia Orion RTN-10X fire control system with Type 912 radar and was fitted only to the
Type 21 frigate. This variant saw active service in the Falklands.
Tigercat A land-based mobile version of Seacat based on a three-round, trailer-mounted launcher towed by a
Land Rover with a second trailer carrying fire control equipment. Tigercat was used exclusively by 48 Squadron
RAF Regiment between 1967 and 1978, before being replaced by
Rapier. Tigercat was also operated by; India, Iran, Jordan, South Africa and Qatar and saw limited service in the
1982 Falklands War with Argentina.
Hellcat "Hellcat", an air-to-surface version to give British
Westland Wasp or
Westland Wessex HU.5 helicopters a capability against
fast attack craft and other high-speed naval targets, was considered in the late 1960s. Two missiles would be carried on a pair of pylons on the helicopter, with an optical sight mounted through the cabin roof. Hellcat was also considered for
counter-insurgency (COIN) purposes, with four missiles carried on a militarised
Short Skyvan. Despite being offered by Shorts for some years, it does not seem to have been sold.
Seacat Target "Seacat Target"" is a specialised target vehicle based on the Seacat and is used to simulate sea-skimming missiles for practising a ship's air defence against. Introduced in 1986 it uses the first and second stages of Seacat with the addition of a special target head in place of the missile's warhead. The target missile can be fired from the standard Seacat launcher. ==Service==