Searchwater was a maritime

surveillance Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing, or directing. This can include observation from a distance by means of electronic equipment, such as ...

radar Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...

developed by

Thorn EMI Thorn EMI was a major British company involved in consumer electronics, music, defence and retail. Created when Thorn Electrical Industries merged with EMI in October 1979, it was listed on the London Stock Exchange and was once a constituen ...

under project P1149. This type of radar has been in service with the

Royal Air Force The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...

Hawker Siddeley Nimrod The Hawker Siddeley Nimrod is a retired maritime patrol aircraft developed and operated by the United Kingdom. It was an extensive modification of the de Havilland Comet, the world's first operational jet airliner. It was originally designed ...

aboard the MR2 variant since the 1970s. The retirement of the Royal Navy's fleet carriers in 1978 meant that the

airborne early warning An airborne early warning and control (AEW&C) system is an airborne radar early warning system designed to detect aircraft, ships, vehicles, missiles and other incoming projectiles at long ranges, as well as performing command and control of t ...

(AEW) capable

Fairey Gannet The Fairey Gannet is a carrier-borne aircraft that was designed and produced by the British aircraft manufacturer the Fairey Aviation Company. It was developed for the Royal Navy, being the first fixed-wing aircraft to combine both the search an ...

was also withdrawn from service. During the

Falklands War The Falklands War () was a ten-week undeclared war between Argentina and the United Kingdom in 1982 over two British Overseas Territories, British dependent territories in the South Atlantic: the Falkland Islands and Falkland Islands Dependenci ...

, a number of warships were lost due to the lack of an indigenous AEW presence. Consequently, a greatly accelerated project was started to equip

Westland Sea King The Westland WS-61 Sea King is a British licence-built version of the American Sikorsky S-61 helicopter of the same name, built by Westland Helicopters. The aircraft differs considerably from the American version, with Rolls-Royce Gnome eng ...

helicopters with a slightly modified version of the system known as Searchwater LAST (Low Altitude Surveillance Task). The radome was mounted in a distinctive inverted cupola on a swivel arm attached to the right side of the fuselage just aft of the main door.Westland Sea King AEW2 and ASaC.7
/ref> This arm allowed the helicopter to lower the radar below the fuselage in flight and to raise it for landing. Searchwater was retired from service when the last of the Royal Navy's airborne early warning Sea King helicopters were taken out of service in 2018. The Searchwater system was subsequently replaced in the Royal Navy by the new Crowsnest system. Searchwater radar was developed by the

Royal Signals and Radar Establishment The Royal Signals and Radar Establishment (RSRE) was a scientific research establishment within the Ministry of Defence (MoD) of the United Kingdom. It was located primarily at Malvern in Worcestershire, England. The RSRE motto was ''Ubique ...

and

EMI EMI Group Limited (formerly EMI Group plc until 2007; originally an initialism for Electric and Musical Industries, also referred to as EMI Records or simply EMI) was a British transnational conglomerate founded in March 1931 in London. At t ...

(later

Thorn Sensors Group Thorn(s) or The Thorn(s) may refer to: Botany * Thorns, spines, and prickles, sharp structures on plants * ''Crataegus monogyna'', or common hawthorn, a plant species Comics and literature * Rose and Thorn, the two personalities of two DC Comic ...

). Racal Radar Defence Systems acquired Searchwater in 1995. Thorn and Racal merged to form Racal-Thorn Defence.

Variants

*Searchwater: the first model of the family, basic anti-submarine and anti-surface warfare (ASW/AsuW) radar without air-to-air capability, installed on board

MR2 ASW aircraft. *Searchwater AEW: Also known as Searchwater LAST (Low Altitude Surveillance Task), the AEW version for helicopters as a lesson learned from the Falklands War. *Skymaster: Development of Searchwater AEW/LAST, combining the air-to-surface capability of the original Searchwater and the air-to-air capability of Searchwater AEW/LAST. Developed as the radar for Argus-2000 AEW&C system to be installed on

British Aerospace Nimrod AEW3 The British Aerospace Nimrod AEW3 was a proposed airborne early warning and control, airborne early warning (AEW) aircraft which was to provide airborne radar cover for the air defence of the United Kingdom by the Royal Air Force (RAF). The pr ...

. which was eventually cancelled. However, 6 complete Argus-2000 AEW&C systems plus two more Skymaster radar as spares were purchased by China in 1997 for 66 million US dollars. The experienced gained from Skymaster/Argus-2000 program despite its eventual cancellation has been used in the modernization of other models of Searchwater radars. *Searchwater 2000: Upgrade package of Searchwater series including the integration of

Link 11 TADIL-A/Link 11 is a secure half-duplex tactical data link used by NATO to exchange digital data. It was originally developed by a joint committee including members from the Royal Canadian Navy, US Navy and Royal Navy to pass accurate targeting ...

and

Link 16 Link 16 is a military tactical data link network used by NATO members and other nations, as allowed by the MIDS International Program Office (IPO). Its specification is part of the family of Tactical Data Links. Link 16 enables military aircra ...

, faster computers and advanced operator console with coloured display. Installed on Sea King Mk 7 and successfully deployed in Afghanistan with over a thousand missions performed. *Searchwater 2000 AEW: latest AEW model of Searchwater radars developed from Skymaster and Searchwater 2000, with the incorporation of moving target indication (MTI), compatibility with

Link 22 Link 22 is a secure digital radio link in the high frequency (HF) and ultra high frequency (UHF) bands, primarily used by military forces as a tactical data link. Link 22 provides beyond line-of-sight (BLOS) communications. It interconnects air, ...

, and improved capability in littoral water. *Searchwater 2000 MR: Intended for the cancelled

BAE Systems Nimrod MRA4 The BAE Systems Nimrod MRA4 was a planned maritime patrol and attack aircraft intended to replace the Hawker Siddeley Nimrod MR2. The rebuilt aircraft would have extended the operating life of the Nimrod fleet by several decades and signific ...

; it has

synthetic aperture radar Synthetic-aperture radar (SAR) is a form of radar that is used to create two-dimensional images or 3D reconstruction, three-dimensional reconstructions of objects, such as landscapes. SAR uses the motion of the radar antenna over a target regi ...

and

inverse synthetic aperture radar Inverse synthetic-aperture radar (ISAR) is a radar technique using radar imaging to generate a two-dimensional high resolution image of a target. It is analogous to conventional SAR, except that ISAR technology uses the movement of the target rat ...

modes. *Searchwater ASaC: Latest member of Searchwater radar family with ground moving target indication capability added, specifically designed for AEW&C applications over land and sea.Searchwater ASaC
/ref>

References

{{Reflist Aircraft radars Military radars of the United Kingdom Military equipment introduced in the 1970s

Variants

See also

References