Seaslug was a first-generation surface-to-air missile designed by Armstrong Whitworth (later part of the Hawker Siddeley group) for use by the Royal Navy. Tracing its history as far back as 1943's LOPGAP design, it came into operational service in 1961 and was still in use at the time of the Falklands War in 1982. Seaslug was intended to engage high-flying targets such as reconnaissance aircraft or bombers before they could launch stand-off weapons. It was only fitted to the Royal Navy's eight County-class destroyers which were designed around the missile system. Seaslug was only fired in anger once as an anti-aircraft missile, from during the Falklands War, but missed its target. Later improvements meant that it could also be used against ships and ground targets. It was planned that Seaslug's medium-range role was to be supplanted by a very long-range missile known as Blue Envoy, but this was passed over in favour of a new medium-range system, Sea Dart. Sea Dart entered service in 1973 on the Type 82 destroyers and replaced Seaslug during the 1980s as the s were removed from service. Development Initial concept In 1943, the German Luftwaffe began the use of anti-shipping missiles and guided bombs in the Mediterranean Sea during Allied operations against Italy. These weapons were released outside of anti-aircraft gun range, which meant that naval operations lacking complete air superiority would be open to attack with no effective response from the ships. A solution for long-range anti-aircraft was required. On 16 March 1944 the first meeting of the "Guided Anti-Aircraft Projectile Committee", or GAP Committee, was held. The Admiralty Signals Establishment (ASE), in charge of the Navy's radar development, was working on new radars featuring radar lock-on that allowed them to accurately track aircraft at long range. This was part of the LRS.1 fire-control system that allowed large dual-purpose guns to attack bombers at long range. A contemporary British Army project at Cossors, Brakemine, was working on a system to allow a missile to keep itself centred within a radar beam, a concept known today as beam riding. The Navy decided to combine the two concepts, using the LRS.1's Type 909 radar with a new missile that differed from Brakemine primarily in requiring longer range and being more robust for shipborne use. In December 1944, GAP put out a Naval Staff Target for a new anti-aircraft weapon, capable of attacking targets at altitudes