Editing Sea Dart (section)

==History==
===Impetus===
From the immediate post-WWII era, the [[Royal Navy]] had been looking for a general-purpose weapon to arm small ships. After the experience with German [[glide bomb]]s during the war, the primary concern was the development of a medium-range [[surface-to-air missile]] able to shoot down the carrier bombers before they could approach the ships within the range of their glide bombs. As this weapon would take up room normally assigned to a [[dual-purpose gun]], the weapon also needed a secondary anti-ship capability. The secondary anti-ship role was later reduced in importance.{{sfn|Friedman|2012|p=255}}

Early experiments during the 1950s led to the development of the [[Seaslug (missile)|Seaslug]] system. Seaslug was useful against first-generation [[strike aircraft]] but had limited performance against faster aircraft or [[anti-ship missile]]s. Seaslug was also too large to be carried by a [[frigate]]-sized ship, leaving smaller ships with little air defence. Some consideration was given to a high-performance gun system for these ships, the DACR (direct-action, close-range), but calculations showed it would be useless against future anti-ship missiles that would manoeuvre on the approach.{{sfn|Friedman|2012|p=256}}

===SIGS===
In October 1960, the Navy launched the Small Ship Integrated Guided Weapon System project to fill this need, SIGS for short. This called for a weapon small enough to be carried on a 3,000 ton frigate and able to attack bombers, anti-shipping missiles, and other ships up to frigate size. Seaslug had taken much longer to develop than expected and was a very costly, ongoing program. There was some concern that development of a new system should not commence before Seaslug was in service. A review by the [[Defence Research Policy Committee]] agreed with the Navy that the new design represented an entirely new class of weapon and that development should be undertaken immediately.{{sfn|Friedman|2012|p=258}}

Two systems were initially considered for the role. [[Bristol Aeroplane Company|Bristol's]] RP.25 was a [[ramjet]] powered design with a long [[wing configuration#Ogival delta|ogive wing]] that was boosted to speed by two detachable booster rockets under the missile in a layout not that different from Bristol's [[Bloodhound (missile)|Bloodhound]] missile. The second was two-stage solid-fuel rocket known as SIG-15 from BAC, developed partially from BAC's work on the PT.428 which would later emerge as [[Rapier (missile)|Rapier]].{{sfn|Gibson|Buttler|2007|p=62}}

The Admiralty considered the range of the BAC entry, about {{convert|16|miles}}, to be too short to be useful. The Bristol concept offered a much more useful maximum around {{convert|50|miles}}. However, it also felt the BAC team, known as Project 502, was better able to manage the project. The Admiralty also demanded that the design be able to be moved about the ship in a fashion similar to gun ammunition, which made the winged RP.25 unsuitable. The result was a redesign effort with BAC designing the airframe and Bristol providing the engine.{{sfn|Gibson|Buttler|2007|p=63}}

===CF.299===
The new design was returned in 1962, and was so promising that the [[Ministry of Aviation]] assigned it the name CF.299 and detailed design began.{{sfn|Gibson|Buttler|2007|p=63}}

A 1966 report estimated that CF.299 would have a two-shot [[Probability of kill|kill probability]] (Pk) against an [[K-10S|AS-2 Kipper]] missile of 0.8–0.9, whereas Seaslug II would manage only 0.35–0.55. Against a supersonic [[Tupolev Tu-22|"Blinder"]] bomber, Pk was 0.5–0.8, compared to 0.3–0.5 for Seaslug. Additionally, because it flew faster than Seaslug, the total engagement time was shorter, and this meant the battery could salvo more rapidly. Finally, its ability to [[deflection (ballistics)|lead the target]], compared to Seaslug's [[beam riding]] [[pursuit course]], allowed it to attack targets with much higher crossing speeds. A 1968 study suggested Sea Dart would have the same capability as eight [[F-4 Phantom]]s on patrol.{{sfn|Friedman|2012|p=257}}

By this time, many European navies had chosen the US [[RIM-24 Tartar]] surface-to-air missiles, but the [[Dutch Navy]] was interested in the British missile for a new class of advanced anti-air ships they were designing. The design mounted an advanced radar system, and an agreement was arranged where the Dutch would use the British missile and the RN ships would use the Dutch radar under the name Type 988 "Broomstick". This was a 3D radar with multiple antennas that provided both fast continual scanning as well as multiple independent targeting radars. Both the radar and missiles would be controlled by a new combat direction system being developed by both navies.{{sfn|Friedman|2012|p=258}}

Ultimately, the Dutch also chose Tartar for their missile component, leaving the Royal Navy as the Sea Dart's only initial user.{{sfn|Friedman|2012|p=258}} The Navy dropped its interest in Broomstick and continued development using simpler radars like the [[Type 965 radar]] that was already in service. This had the disadvantage of not being able to pick out targets against a background landform or high waves, significantly limiting its capabilities against low-flying strike aircraft.{{sfn|Friedman|2012|p=162}}

===Into service===
Sea Dart entered service in 1973 on the sole [[Type 82 destroyer]] {{HMS|Bristol|D23|6}} before widespread deployment on the [[Type 42 destroyer]] commencing with {{HMS|Sheffield|D80|6}} in 1976. The missile system was also fitted to [[Invincible-class aircraft carrier|''Invincible''-class aircraft carriers]] but was removed during refits between 1998 and 2000 to increase the area of the flight deck and below-decks stowage associated with the operation of [[Royal Air Force]] (RAF) [[RAF Harrier II|Harrier GR9]] aircraft.{{sfn|Saunders|2002|p=770}}

In 1982, British Aerospace won a £100m contract to sell the Sea Dart system to [[China]],<ref>{{cite web |title=Defence: Managing Director of British Aerospace letter to MT (sale of Sea Dart weapon system to China) |quote=Thank you for your involvement in our success... This will help to secure jobs [declassified Jan 2014] |url=https://www.margaretthatcher.org/document/222861 |website=Margaret Thatcher Foundation |access-date=1 June 2023}}</ref> but this fell through in 1983, with Chinese minister [[Chen Muhua]] explaining that China was "not satisfied with the price, technology or production".<ref>{{cite news |last1=Mirsky |first1=Jonathan |title=Why China cancelled £100m Sea Dart order |work=The Observer |date=1983-04-03}}</ref>

===Proposed versions===
During the late 1970s, British Aerospace proposed a Sea Dart II, which replaced the original's transistor-based electronics with [[integrated circuit]]s that so reduced the size of the equipment that it allowed for a useful increase in fuel storage and range. British Aerospace also outlined a new version of the Chow booster that included [[thrust vector control]] that would allow it to be stored vertically on new platforms or make radical maneuvers when launching from the existing launch rail systems. Development was cancelled in the 1980 Defence Review by the Minister of Defence, John Nott. Another short-lived project was Sea Daws 100, which used a single-rail launcher for a future Type 82 replacement.{{sfn|Gibson|Buttler|2007|p=63}}

[[Hawker Siddeley Dynamics]], which had taken over Bristol, proposed using the Sea Dart missile as a replacement for both the [[British Army]]'s [[Thunderbird (missile)|Thunderbird]] and the RAF's [[Bloodhound (missile)|Bloodhound]]. This Land Dart was launched from a four-round box that would be highly mobile. Hawker Siddeley Dynamics suggested that if the missile was used by all three British services, it would result in further sales as a [[NATO]]-standard SAM. The introduction of the VR.725 Thunderbird II led the Army to drop any interest in Land Dart, and the NATO contract eventually went to the [[MIM-23 Hawk]].{{sfn|Gibson|Buttler|2007|p=64}}

Hawker Siddeley tried again in the 1970s when the Air Staff released GAST.1210, calling for a long-range missile to replace Bloodhound. It proposed a further updated Land Dart combined with a dramatically improved radar system, the Plessey GF75 Panther, a land-based version of the naval AWS-5. This concept ultimately went nowhere and the Bloodhound was removed from service in 1991 with no replacement.{{sfn|Gibson|Buttler|2007|p=64}} In the early 1980s, [[British Aerospace]] (BAe), who had taken over Hawker, re-launched the GAST.1210 concept under the new name Guardian. This proposed a lightweight two-round launcher and mobile version of Panther to be used as both a SAM and an anti-missile for short-range [[ballistic missile]]s like [[SCUD]]. Despite interest from the Middle East, no sales followed. The same launcher was also offered as Lightweight Sea Dart, which used its disposable shipping container as the launch tube, which was fit into a four-place trainable launcher that could also mount [[Sea Eagle (missile)|Sea Eagle]]. Most of the weight savings was in the launcher itself, allowing it to be fit to smaller ships.<ref>{{cite magazine |first=Richard |last=Whitaker |title=Sea Dart loses weight |magazine=Flight International |date=26 February 1983 |page=532}}</ref>

===Updates===
Experience in the [[Falklands War]] demonstrated that the mix of systems used to support Sea Dart put it at a significant disadvantage despite the missile itself being highly potent. This led to a series of updates to both the missile and the radars equipping the ''Sheffield''-class destroyers.

The first upgrade was to replace the older Type 965 radar with the much better Type 1022. The Navy had originally planned on replacing the 965 with a new radar, then known as STIR, when it became available. As it became clear that STIR would not be available for some time, [[Marconi]] offered an interim model, the 1022. This had a new antenna design that greatly reduced the beamwidth from around 12 degrees to 2.3, and used a shaped broadcast pattern that greatly reduced the amount of signal that was aimed at waves and thereby reduced clutter.

The 1022 arrived in time to equip the "Batch II" Sheffields, which began in 1978 with HMS ''Exeter''. Initially they had planned to re-equip the earlier ships as well, but as the new ships started arriving all desire to spend the money on the upgrades disappeared. As many of the problems with the Sea Dart could be traced to the failure of the 965 to provide any early warning against low-level engagements, the ability to offer dramatically improved performance with a relatively simple update that had been planned all along was suddenly considered very important.