armed the proxy fuse (infra-red) at about from the target, if 'hot', while if 'cold' the missile was detonated by command sent from the ship. The range could be even more than 35,000 yards, especially at high altitude, with head-on supersonic targets. One of the longest shots recorded was made by HMS Antrim against a target over away, with an impact at 34.500 with about 46 seconds flight time. The missile was capable to reach potentially aven higher altitude and longer range than nominally assested: even after the engine flameout (over 40 seconds after launch), it retained very high speeds, and one of them even surpassed before being self-destructed, about one minute after the firing For both Mark 1 and Mark 2 Sea Slug there were drill rounds (painted blue) for the purpose of training and display rounds (painted red) which could be loaded onto the launcher for port visits and public relations. Nuclear variant (not built) In addition, a nuclear-armed variant was planned using a low-yield fission warhead code-named Winkle. Winkle was never built as it was quickly supplanted by Pixie, a very small unboosted warhead with an all-plutonium fissile core tested at Maralinga, which was, in turn, replaced by Gwen — a British version of the US W54 Gnat unboosted warhead of approximate yield 0.5–2 kiloton of TNT-equivalent. The final warhead choice was Tony - a UK version of the W44 Tsetse boosted warhead, but all nuclear options for Seaslug were subsequently abandoned, and no nuclear-armed variant of Seaslug was ever deployed. Operators Royal Navy The County-class destroyers were specifically built to carry Seaslug and its associated control equipment. The magazine was positioned amidships and missiles were assembled in a central gallery forward of the magazine before being passed to the launcher on the quarterdeck. The handling arrangements were designed with a nuclear-war environment in mind and were therefore entirely under cover. Chilean Navy Some of the County-class destroyers were sold to Chile for the Chilean Navy. The system was decommissioned after the rebuild of the four ships purchased by Chile in the early 1990s. Former operators : Chilean Navy : Royal Navy Notes References Bibliography Bibliography Naval Armament, Doug Richardson, Jane's Publishing, 1981, External links Sea Slug Video "Seaslug - the Most Missile in the Least Space" a 1958 Flight article by Bill Gunston "Shell for the Seaslug" a 1959 article on Seaslug in Flight magazine "Seaslug