Editing Airborne early warning and control

{{short description|Airborne system of surveillance radar plus command and control functions}}
{{Use dmy dates|date=April 2022}}
[[File:Royal Air Force (RAF) E-3D Sentry AEW1 (airborne early warning) aircraft, registration ZH106, taking part in Exercise Taurus Mountain 3, in the skies over North Yorkshire in March 2012 - MOD 45153803 (cropped).jpg|thumb|upright=1.1|A [[Royal Air Force]] [[Boeing E-3 Sentry]] over [[North Yorkshire]]]]

An '''airborne early warning and control''' ('''AEW&C''') system is an airborne [[radar]] [[early warning system]] designed to detect [[aircraft]], [[ship]]s, [[vehicle]]s, [[missile]]s and other incoming [[projectile]]s at long ranges, as well as performing [[command and control]] of the [[battlespace]] in [[aerial warfare|aerial engagement]]s by informing and directing friendly [[fighter aircraft|fighter]] and [[attack aircraft]]. AEW&C units are also used to carry out [[aerial surveillance]] [[airborne ground surveillance|over ground]] and [[maritime surveillance|maritime targets]], and frequently perform [[battle management]] command and control (BMC2). When used at altitude, the radar system on AEW&C aircraft allows the operators to detect, track and prioritize targets and identify friendly aircraft from hostile ones in real-time and from much farther away than ground-based radars.<ref>Neufeld 1997, p. 276.</ref> Like ground-based radars, AEW&C systems can be detected and targeted by opposing forces, but due to aircraft mobility and extended sensor range, they are much less vulnerable to counter-attacks than ground systems.<ref>Neufeld 1997, p. 278.</ref>

AEW&C aircraft are used for both defensive and offensive air operations, and serve [[air force]]s in the same role as what the [[combat information center]] is to [[naval]] [[warship]]s, in addition to being a highly mobile and powerful radar platform. So useful and advantageous is it to have such aircraft operating at a high altitude, that some navies also operate AEW&C aircraft for their warships at sea, either coastal- or [[carrier-based]] and on both [[fixed-wing]] and [[rotary-wing]] platforms. In the case of the [[United States Navy]], the [[Northrop Grumman E-2 Hawkeye]] AEW&C aircraft is assigned to its [[supercarrier]]s to protect them and augment their onboard command information centers (CICs). The designation "airborne early warning" (AEW) was used for earlier similar aircraft used in the less-demanding [[radar picket]] role,<ref>Gordon 2010, p. 3.</ref> such as the [[Fairey Gannet AEW.3]] and [[Lockheed EC-121 Warning Star]], and continues to be used by the RAF for its [[Boeing E-3 Sentry|Sentry AEW1]], while AEW&C (airborne early warning and control) emphasizes the [[Command and control (military)|command and control]] capabilities that may not be present on smaller or simpler radar picket aircraft. '''AWACS''' (Airborne Warning and Control System) is the name of the specific system installed in the American [[Boeing E-3 Sentry]] and Japanese [[Boeing E-767]] AEW&C airframes, but is often used as a general synonym for AEW&C.<ref>{{Cite web|url=https://boeing.mediaroom.com/1998-03-11-Boeing-Delivers-First-Two-767-AWACS-Introduces-Newest-Member-of-AEW-C-Family|title=Boeing Delivers First Two 767 AWACS, Introduces Newest Member of AEW&C Family|website=MediaRoom}}</ref><ref name=gap />

==General characteristics==
[[File:Wellington Ic (R1629).jpg|thumb|Wellington Ic "Air Controlled Interception" showing rotating radar antenna]]

Modern AEW&C systems can detect aircraft from up to {{convert|400|km|nmi|abbr=on}} away, well out of range of most surface-to-air missiles. One AEW&C aircraft flying at {{convert|9000|m|abbr=on}} can cover an area of {{convert|312000|km2|abbr=on}}. Three such aircraft in overlapping orbits can cover the whole of [[Central Europe]].<ref>{{cite web |url=http://www.nato.int/nato_static/assets/pdf/pdf_publications/20120103_awacs-e.pdf |title=AWACS: Nato's eyes in the sky |publisher=Nato }}</ref> AEW&C system indicates close and far proximity range on threats and targets, help extend the range of their sensors, and make offensive aircraft harder to track by avoiding the need for them to keep their own radar active, which the enemy can detect. Systems also communicate with friendly aircraft, vectoring fighters towards hostile aircraft or any [[unidentified flying object]].

==History of development==
After having developed [[Chain Home]]—the first ground-based [[early-warning radar]] detection system—in the 1930s, the [[Cavity magnetron|British developed a radar set]] that could be carried on an aircraft for what they termed "Air Controlled Interception". The intention was to cover the North West approaches where German long range [[Focke-Wulf Fw 200 Condor]] aircraft were threatening shipping. A [[Vickers Wellington]] bomber (serial R1629) was fitted with a rotating antenna array. It was tested for use against aerial targets and then for possible use against German [[E boat]]s.<ref>''Air-Britain'', Aviation World, 2004,</ref><ref>Hodges, R, "Air controlled interception," ''Radar Development to 1945'' R W Burns (ed),</ref> Another radar equipped Wellington with a different installation was used to direct [[Bristol Beaufighter]]s toward [[Heinkel He 111]]s, which were air-launching [[V-1 flying bomb]]s.<ref>''Flypast''m April 1987: "The First AWACS".</ref><ref>R.H. Hamilton in Perkins, L.W., ed., Flight into Yesterday – A Memory or Two from Members of the Wartime Aircrew Club of Kelowna, L.P. Laserprint, Ltd., Kelowna, B.C., 2000, and 407 Squadron History 1941–1996 – a Narrative History, 407 Squadron, 1996.</ref>

In February 1944, the US Navy ordered the development of a radar system that could be carried aloft in an aircraft under Project Cadillac.<ref>Hirst 1983, p. 59.</ref> A prototype system was built and flown in August on a modified [[Grumman TBF Avenger|TBM Avenger]] [[torpedo bomber]]. Tests were successful, with the system being able to detect low flying formations at a range greater than {{convert|100|mi|km}}. US Navy then ordered production of the TBM-3W, the first production AEW aircraft to enter service. TBM-3Ws fitted with the [[AN/APS-20]] radar entered service in March 1945, with 27 eventually constructed.<ref>Hirst 1983, p. 64.</ref> It was also recognised that a larger land-based aircraft would be attractive, thus, under the ''Cadillac II'' program, multiple [[Boeing B-17 Flying Fortress|Boeing B-17G Flying Fortress]] bombers were also outfitted with the same radar.<ref>Hirst 1983, p. 60.</ref>
[[File:Lockheed EC-121M with F-4B (cropped).jpg|thumb|left|[[Lockheed EC-121]]M one of the first AEW aircraft]]
The [[Lockheed EC-121 Warning Star|Lockheed WV and EC-121 Warning Star]], which first flew in 1949, served widely with US Air Force and US Navy. It provided the main AEW coverage for US forces during the Vietnam war.<ref name="jtc">Corell, John T. [https://web.archive.org/web/20080513063318/http://www.afa.org/magazine/Nov2004/1104igloo.asp "Igloo White."] ''Air Force Magazine,''  Vol. 87, No. 11, November 2004 via ''web.archive.org''. Retrieved: 23 December 2010.</ref> It remained operational until replaced with the E-3 AWACS.<ref>Wilson 1998, p.&nbsp;72.</ref> Developed roughly in parallel, [[N-class blimp]]s were also used as AEW aircraft, filling gaps in radar coverage for the continental US, their tremendous endurance of over 200 hours being a major asset in an AEW aircraft.<ref>[https://books.google.com/books?id=jNwDAAAAMBAJ&dq=true&pg=PA117 "Navy Airship Longer Than Football Field."] ''Popular Mechanics'', September 1952, p. 117, bottom.</ref><ref name=SkyShips>''Sky Ships: A History of the Airship in the United States Navy'', Althoff, W.F., Pacifica Press, c1991, {{ISBN|0-935553-32-0}}</ref> Following a crash, the US Navy opted to discontinue lighter than air operations in 1962.<ref>{{cite web |url =http://www.navytimes.com/news/2011/10/gannett-navy-after-50-years-airship-program-resumes-102711/ |title = After 50 years, Navy resumes airship program |publisher = Navy Times |first = Kirk |last = Moore |date = 27 October 2011}}</ref>

In 1958, the [[Soviet Union|Soviet]] [[Tupolev|Tupolev Design Bureau]] was ordered to design an AEW aircraft.<ref name=Tu-114.1>Gordon 2006, p. 86.</ref> After determining that the projected radar instrumentation would not fit in a [[Tupolev Tu-95]] or a [[Tupolev Tu-116]], the decision was made to use the more capacious [[Tupolev Tu-114]] instead.<ref name=Tu-114.1 /> This solved the problems with cooling and operator space that existed with the narrower Tu-95 and Tu-116 fuselage.<ref name=Tu-114.1 /> To meet range requirements, production examples were fitted with an air-to-air refueling probe.<ref name=Tu-114.2>Gordon 2006, p. 87.</ref> The resulting system, the [[Tupolev Tu-126]], entered service in 1965 with the [[Soviet Air Forces]] and remained in service until replaced by the [[Beriev A-50]] in 1984.<ref name=Tu-114.2 />

During the Cold war, United Kingdom deployed a substantial AEW capability, initially with American [[Douglas A-1 Skyraider|Douglas AD-4W Skyraiders]], designated Skyraider AEW.1, which in turn were replaced by the [[Fairey Gannet AEW|Fairey Gannet AEW.3]], using the same AN/APS-20 radar.<ref name="Gibson10">{{harvnb|Gibson|2011|p=10}}</ref> With the retirement of conventional aircraft carriers, the Gannet was withdrawn and the [[Royal Air Force]] (RAF) installed the radars from the Gannets on [[Avro Shackleton]] MR.2 airframes, redesignated Shackleton AEW.2.<ref name ="Tyack 87"/> To replace the Shackleton AEW.2, an AEW variant of the [[Hawker Siddeley Nimrod]], known as the [[British Aerospace Nimrod AEW3|Nimrod AEW3]], was ordered in 1974. After a protracted and problematic development, this was cancelled in 1986, and seven E-3Ds, [[British military aircraft designation systems|designated]] Sentry AEW.1 in RAF service, were purchased instead.<ref name="spyflight">[http://www.spyflight.co.uk/nim%20aew.htm "BAe Nimrod AEW 3."] {{Webarchive|url=https://web.archive.org/web/20120502141328/http://www.spyflight.co.uk/Nim%20aew.htm |date=2 May 2012 }} ''Spyflight.'' Retrieved: 21 October 2010.</ref><ref name ="Tyack 87">Tyack 2005, p. 87.</ref>

The US Defense Department is considering options to move the air moving target indicator (AMTI) mission component from AWACS aircraft to space-based platforms. The space-based sensor is already in orbit and in testing phase.<ref>
https://aviationweek.com/defense/sensors-electronic-warfare/norad-commander-amti-prototype-sensors-are-orbit-now</ref>

==Current systems==

Many countries have developed their own AEW&C systems, although the [[Boeing E-3 Sentry]], [[Boeing E-7 Wedgetail|E-7A]]<ref>{{Cite web |last=Tirpak |first=John |date=2023-11-17 |title=NATO Picks E-7 as Its New AWACS; Six Aircraft to Start |url=https://www.airandspaceforces.com/nato-e-7-new-awacs-six-aircraft/ |access-date=2024-01-24 |website=Air & Space Forces Magazine |language=en-US}}</ref> and [[Northrop Grumman E-2 Hawkeye]] and Gulfstream/IAI [[EL/W-2085]] are the most common systems worldwide.

===Airborne Warning and Control System (AWACS)===
[[File:Boeing E-767 (light).jpg|thumb|right|[[Boeing E-767|E-767]] of the [[Japan Air Self Defense Force]]]]
{{see also|Boeing E-3 Sentry}}
[[Boeing]] produces a specific system with a "[[rotodome]]" rotating [[radome]] that incorporates [[Westinghouse Electronic Systems|Westinghouse]] (now [[Northrop Grumman]]) radar.<ref name="gap">{{cite web |url=http://www.airpower.maxwell.af.mil/airchronicles/aureview/1972/may-jun/pearce.html |title=AWACS to Bridge the Technological Gap |access-date=14 February 2009 |publisher=Air University |archive-url=https://web.archive.org/web/20040627142853/http://www.airpower.maxwell.af.mil/airchronicles/aureview/1972/may-jun/pearce.html |archive-date=27 June 2004 |url-status=dead}}</ref> It is mounted on either the [[E-3 Sentry]] aircraft ([[Boeing 707]]) or more recently the [[Boeing E-767]] ([[Boeing 767]]), the latter only being used by the [[Japan Air Self-Defense Force]].<ref name=aw30>Air World, April 1998 Special edition "Airborne Early Warning and Control aircraft E-767 & E-3" p. 30.</ref>

When AWACS first entered service it represented a major advance in capability, being the first AEW to use a [[pulse-Doppler radar]], which allowed it to track targets normally lost in ground clutter.<ref name=USAF>Neufeld 1997, p. 271.</ref> Previously, low-flying aircraft could only be readily tracked over water.<ref name=USAF /> The AWACS features a [[3D radar|three-dimensional radar]] that measures azimuth, range, and elevation simultaneously; the  AN/APY-2 unit installed upon the E-767 and later E-3 models has superior surveillance capability over water compared to the AN/APY-1 system on the earlier E-3 models.<ref name=aw37>Air World, April 1998 Special edition "Airborne Early Warning and Control aircraft E-767 & E-3" p. 37.</ref><ref name=boeing_e-767-overview>[http://www.boeing.com/defense-space/ic/awacs/767/767overview.html Boeing 767 AWACS Overview] {{webarchive |url=https://web.archive.org/web/20070604152457/http://www.boeing.com/defense-space/ic/awacs/767/767overview.html |date=June 4, 2007 }}. Boeing</ref>

===E-2 Hawkeye===
{{main|Grumman E-2 Hawkeye}}

The E-2 Hawkeye was a specially designed AEW aircraft. Upon its entry to service in 1965, it was initially plagued by technical issues, causing a (later reversed) cancellation.<ref name="JAWA76 p291">Taylor 1976, p. 291.</ref> Procurement resumed after efforts to improve reliability, such as replacement of the original rotary drum computer used for processing radar information by a Litton L-304 digital computer.<ref>{{cite journal |title=across the editor's desk: COMPUTING AND DATA PROCESSING NEWSLETTER – LITTON'S L-304 |journal=Computers and Automation |date=Oct 1965 |volume=14 |issue=10 |pages=43–44 |url=https://archive.org/details/bitsavers_computersA_7957328/page/n41?q=%22monolithic+silicon+integrated+and+hybrid%22}}
*{{cite journal|title=COMPUTERS AND DATA PROCESSORS, NORTH AMERICA: 4. Litton Industries, Guidance and Control Systems Division, L-304 Militarized Computer, Woodland Hills, California|journal=Digital Computer Newsletter|date=Jan 1966|volume=18|issue=1|page=23|url=http://www.dtic.mil/docs/citations/AD0694647|language=en|access-date=February 25, 2019|archive-url=https://web.archive.org/web/20180603105832/http://www.dtic.mil/docs/citations/AD0694647|archive-date=June 3, 2018|url-status=dead}}</ref><ref>{{cite web|url=https://archive.org/details/bitsavers_littonL304mputerSystemSep66_6953238/page/n7|title=The Litton L-304 Dual Computer System|date=1966|work=trailing-edge.com|page=2|access-date=August 1, 2016|quote=L-304E with 4096 words of memory was completed and put in operation. Very shortly thereafter, the computer was tied to a typewriter, paper tape reader and punch, a small magnetic tape, a real-time clock and a small CRT display and control console.}} [http://bitsavers.trailing-edge.com/pdf/litton/L-304/The_Litton_L-304_Dual_Computer_System_Sep66.pdf Alt URL]
* {{cite journal|date=Dec 1967|title=1967 Pictorial Report on the Computer Field: DIGITAL COMPUTERS – TACTICAL AUTOMATIC DATA PROCESSING SYSTEM (TADPS)|url=https://archive.org/details/bitsavers_computersA_11280381/page/n33?q=%22TACTICAL+AUTOMATIC+DATA+PROCESSING+SYSTEM+%28TADPS%29%22|journal=Computers and Automation|issue=12|page=35}}</ref> In addition to purchases by the US Navy, the E-2 Hawkeye has been sold to the armed forces of [[Egypt]], [[France]], [[Israel]], [[Japan]], [[Singapore]] and [[Taiwan]].<ref name="World Aircraft">Donald, David, ed. "Grumman E-2 Hawkeye/TE-2/C-2 Greyhound". ''The Complete Encyclopedia of World Aircraft''. Barnes & Nobel Books, 1997. {{ISBN|0-7607-0592-5}}.</ref>

The latest E-2 version is the ''E-2D Advanced Hawkeye'', which features the new {{anchor|AN/APY-9}}AN/APY-9 radar.<ref>{{cite news |last=Majumdar |first=Dave |date=16 October 2014 |title=Navy Declares IOC For E-2D Advanced Hawkeye |url=http://news.usni.org/2014/10/16/navy-declares-ioc-e-2d-advanced-hawkeye |work=US Naval Institute |access-date=25 July 2015 |archive-url=https://web.archive.org/web/20150724120529/http://news.usni.org/2014/10/16/navy-declares-ioc-e-2d-advanced-hawkeye |archive-date=24 July 2015 |url-status=dead }}</ref> The APY-9 radar has been speculated to be capable of detecting fighter-sized stealth aircraft, which are typically optimized against high frequencies like Ka, Ku, X, C and parts of the S-bands. Historically, UHF radars had resolution and detection issues that made them ineffective for accurate targeting and fire control; Northrop Grumman and Lockheed claim that the APY-9 has solved these shortcomings in the APY-9 using advanced electronic scanning and high digital computing power via space/time adaptive processing.<ref>[http://news.usni.org/2014/06/09/u-s-navys-secret-counter-stealth-weapon-hiding-plain-sight The U.S. Navy's Secret Counter-Stealth Weapon Could Be Hiding in Plain Sight] {{Webarchive|url=https://web.archive.org/web/20140709141815/http://news.usni.org/2014/06/09/u-s-navys-secret-counter-stealth-weapon-hiding-plain-sight |date=9 July 2014}} – News.USNI.org, 9 June 2014.</ref>

===Beriev A-50===
{{Main|Beriev A-50}}
[[File:Самолет ДРЛО А-50У (1).png|thumb|Beriev A-50]]
The Russian Aerospace Forces are currently using approximately 3-5 [[Beriev A-50|Beriev A-50 and A-50U "Shmel"]] in the AEW role. The "Mainstay" is based on the [[Ilyushin Il-76]] airframe, with a large non-rotating disk radome on the rear fuselage. These replaced the 12 [[Tupolev Tu-126]] that filled the role previously. The A-50 and A-50U will eventually be replaced by the [[Beriev A-100]], which features an AESA array in the radome and is based on the updated Il-476.<ref>Butowski, Piotr. "Model Reveals A-100 Configuration". ''[[Air International]]'', April 2014. Retrieved: 21 July 2014.</ref>

===KJ-2000===
{{main|KJ-2000}}
[[File:KJ2000 at 2014 Zhuhai Air Show.jpg|left|thumb|KJ-2000 at 2014 Zhuhai Air Show]]
In May 1997, Russia and Israel agreed to jointly fulfill an order from China to develop and deliver an early warning system. China reportedly ordered one [[EL/M-2075|Phalcon]] for $250 million, which entailed retrofitting a Russian-made Ilyushin-76 cargo plane [also incorrectly reported as a Beriev A-50 Mainstay] with advanced Elta electronic, computer, radar and communications systems. Beijing was expected to acquire several Phalcon AEW systems, and reportedly could buy at least three more [and possibly up to eight] of these systems, the prototype of which was planned for testing beginning in 2000. In July 2000, the US pressured Israel to back out of the $1 billion agreement to sell China four Phalcon phased-array radar systems. Following the cancelled A-50I/Phalcon deal, China turned to indigenous solutions. The Phalcon radar and other electronic systems were taken off from the unfinished Il-76, and the airframe was handed to China via Russia in 2002. The Chinese AWACS has a unique phased array radar (PAR) carried in a round radome. Unlike the US AWACS aircraft, which rotate their rotodomes to give a 360 degree coverage, the radar antenna of the Chinese AWACS does not rotate. Instead, three PAR antenna modules are placed in a triangular configuration inside the round radome to provide a 360 degree coverage. The installation of equipment at the Il-76 began in late 2002 aircraft by Xian aircraft industries (Xian Aircraft Industry Co.). The first flight of an airplane [[KJ-2000]] made in November 2003. All four machines will be equipped with this type. The last to be introduced into service the Chinese Air Force until the end of 2007.{{citation needed|date=January 2024}} China is also developing a carrier-based AEW&C, [[Xian KJ-600]] via Y-7 derived Xian JZY-01 testbed.

===EL/W-2085 AEW&C===
{{main|EL/W-2085}}
[[File:RSAF Gulfstream IAI G550 CAEW (cropped).jpg|left|thumb|Republic of Singapore Air Force Gulfstream G550 CAEW]]
The EL/W-2085 is an airborne early warning and control (AEW&C) multi-band radar system developed by Israel Aerospace Industries (IAI) and its subsidiary Elta Systems of Israel. Its primary objective is to provide intelligence to maintain air superiority and conduct surveillance. The system is currently in service with Israel, Italy, and Singapore.
Instead of using a rotodome, a moving radar was found on some AEW&C aircraft, and the EL/W-2085 used an active electronically scanned array (AESA) – an active phased array radar. This radar consists of an array of transmit/receive (T/R) modules that allow a beam to be electronically steered, making a physically rotating rotodome unnecessary.

AESA radars operate on a pseudorandom set of frequencies and also have very short scanning rates, which makes them difficult to detect and jam. Up to 1000 targets can be tracked simultaneously to a range of 243&nbsp;mi (450&nbsp;km), while at the same time, multitudes of air-to-air interceptions or air-to-surface (including maritime) attacks can be guided simultaneously. The radar equipment of the Israeli AEW&C consists of each L-band radar on the left and right sides of the fuselage and each S-band antenna in the nose and tail. The phased array allows aircraft positions on operator screens to be updated every 2–4 seconds rather than every 10 seconds, as is the case on the rotodome AWACS.<ref>{{URL|https://www.airforce-technology.com/projects/caew/}}</ref>

ELTA was the first company to introduce an Active Electronically Scanned Array Airborne (AESA) Early Warning Aircraft and implement advanced mission aircraft using efficient, high-performance business jet platforms.

===Netra AEW&CS===
{{Main|DRDO AEW&CS}}
[[File:DRDO AEW&C Embraer ERJ 145.JPG|thumb|Netra AEW&C in Aero India 2017]]
In 2003, the [[Indian Air Force]] (IAF) and [[Defence Research and Development Organisation]] (DRDO) began a study of requirements for developing an Airborne Early Warning and Control (AWAC) system.<ref>{{cite press release |title= Development of Airborne Early Warning and Control System |publisher= Press Information Bureau, [[Government of India|GoI]] |date= 11 December 2003 |url= http://pib.nic.in/release/release.asp?relid=123 |access-date = 25 July 2008}}</ref> In 2015, DRDO delivered 3 AWACs, called [[DRDO AEW&CS|Netra]], to the IAF with an advanced Indian AESA radar system fitted on the Brazilian [[Embraer ERJ family#Military models|Embraer EMB-145]] air frame.<ref name=":0">{{Cite news |url=http://www.thehindu.com/news/national/india-to-fill-gaps-in-aerial-vigilance/article17372941.ece |title=India to fill gaps in aerial vigilance |last=Peri |first=Dinaker |work=The Hindu |access-date=27 February 2017 |language=en}}</ref> Netra gives a 240-degree coverage of airspace. The Emb-145 also has air-to-air refuelling capability for longer surveillance time. The IAF also operates three Israeli [[EL/W-2090]] systems, mounted on [[Ilyushin Il-76]] airframes, the first of which first arrived on 25 May 2009.<ref>{{cite news |url=http://www.ynetnews.com/articles/0,7340,L-3721499,00.html |title=Arms deal underway, first Israeli Phalcon lands in India – Israel News |newspaper=Ynetnews |publisher=Ynetnews.com |date=20 June 1995 |access-date=1 June 2009 |archive-url=https://web.archive.org/web/20090528073812/http://www.ynetnews.com/articles/0%2C7340%2CL-3721499%2C00.html |archive-date=28 May 2009 |url-status=live |last1=Ben-Yishai |first1=Ron }}</ref><ref>{{cite web |title=India set to decide big military aircraft deals |url=http://www.indiastrategic.in/topstories1068.htm |publisher=India Strategic |access-date=3 January 2014 |archive-date=3 January 2014 |archive-url=https://web.archive.org/web/20140103181410/http://www.indiastrategic.in/topstories1068.htm |url-status=dead }}</ref> The [[Defence Research and Development Organisation|DRDO]] proposed a more advanced AWACS with a longer range and with a 360-degree coverage akin to the Phalcon system, based on the [[Airbus A330 MRTT#India|Airbus A330]] airframe,<ref name=":0" /><ref>{{cite web |url = https://www.ainonline.com/aviation-news/defense/2019-03-28/india-renews-indigenous-awacs-efforts |title = India Renews Indigenous AWACS Efforts |publisher = ainonline.com |first = Neelam |last = Mathews |date = 28 March 2019}}</ref> but given the costs involved there is also the possibility of converting used A320 airliners as well.<ref name="a320conv1">{{cite web |url = https://www.thedrive.com/the-war-zone/38251/india-plans-to-kit-out-old-airliners-as-early-warning-jets-to-keep-pace-with-its-rivals |title = India To Modify Used Airliners Into Early-Warning Radar Jets To Keep Pace With Its Rivals |first =  Thomas |last = Newdick |date = 18 December 2020 |work = The Warzone |publisher = Brookline Media Inc.}}</ref>

IAF has plans to develop 6 more Netra AEW&CS based on [[Embraer ERJ family#Military models|Embraer EMB-145]] platform<ref>{{Cite news |last=Pubby |first=Manu |date=2023-09-22 |title=IAF plans for six more 'Netra' early warning aircraft |url=https://economictimes.indiatimes.com/news/defence/iaf-plans-for-six-more-netra-early-warning-aircraft/articleshow/103846316.cms?from=mdr |access-date=2024-02-02 |work=The Economic Times |issn=0013-0389}}</ref> and another 6 based on Airbus A321 platform.<ref>{{Cite web |date=2021-09-09 |title=DRDO to develop new early warning jets for IAF under ₹11,000 crore project |url=https://www.hindustantimes.com/india-news/drdo-to-develop-new-early-warning-jets-for-iaf-under-rs-11000-crore-project-101631202114793.html |access-date=2024-02-02 |website=Hindustan Times |language=en}}</ref><ref>{{Cite web |date=16 September 2023 |title=IAF uses Airbus-321 passenger aircraft for ferrying troops to forward areas |url=https://www.aninews.in/news/national/general-news/iaf-uses-airbus-321-passenger-aircraft-for-ferrying-troops-to-forward-areas20230916225250/ |website=aninews.in}}</ref> These systems are expected to have an enhanced performance including range and azimuth

===Boeing 737 AEW&C===
{{Main|Boeing 737 AEW&C}}
[[File:Boeing_737_AEW&C_MESA_Peace_Eagle.jpg|thumb|A [[Turkish Air Force]] Boeing 737 AEW&C]]
The [[Royal Australian Air Force]], [[Republic of Korea Air Force]] and the [[Turkish Air Force]] are deploying [[Boeing 737 AEW&C]] aircraft. The Boeing 737 AEW&C has a fixed, [[active electronically scanned array]] radar antenna instead of a mechanically-rotating one, and is capable of simultaneous air and sea search, fighter control and area search, with a maximum range of over 600&nbsp;km (look-up mode). In addition, the radar antenna array is also doubled as an [[ELINT]] array, with a maximum range of over 850&nbsp;km at {{Convert|9000|m|ft}} altitude.<ref>{{cite web |url=http://articles.janes.com/articles/Janes-Radar-and-Electronic-Warfare-Systems/Multirole-Electronically-Scanned-Array-MESA-radar-United-States.html |title=Defense & Security Intelligence & Analysis: IHS Jane's – IHS |work=janes.com |access-date=7 March 2016 |archive-url=https://web.archive.org/web/20120429073901/http://articles.janes.com/articles/Janes-Radar-and-Electronic-Warfare-Systems/Multirole-Electronically-Scanned-Array-MESA-radar-United-States.html |archive-date=29 April 2012 |url-status=live}}</ref>

===Erieye/GlobalEye===
{{Main|Erieye|GlobalEye}}
[[File:Aeronaves Ágata 7 - FAB - EMB145 Erieye.jpg|thumb|right|A [[Brazilian Air Force]] [[Embraer R-99]]]]
The [[Swedish Air Force]] uses the [[Saab 340 AEW&C|S 100D Argus ASC890]] as its AEW platform. The S 100D Argus is based on the [[Saab 340]] with an [[Ericsson]] [[Erieye radar|Erieye PS-890]] radar. Saab also offers the [[Bombardier Global Express|Bombardier Global 6000]]-based [[GlobalEye]]. In early 2006, the [[Pakistan Air Force]] ordered six [[Erieye]] AEW equipped [[Saab 2000]]s from Sweden.<ref>{{cite web|author= |url=http://www.defenseindustrydaily.com/sweden-finalizes-saab-2000-aewc-contract-with-pakistan-02377/ |title=Sweden Finalizes Saab 2000 AEW&C Contract With Pakistan |publisher=Defenseindustrydaily.com |date=7 April 2008 |access-date=1 June 2009}}</ref> In December 2006, the [[Pakistan Navy]] requested three excess [[P-3 Orion]] aircraft to be equipped with Hawkeye 2000 AEW systems.<ref>{{cite web|url=http://www.c4isrjournal.com/story.php?F=2416333 |title=C4ISRJournal.com |publisher=C4ISRJournal.com |date=11 December 2006 |access-date=1 June 2009 |url-status=dead |archive-url=https://web.archive.org/web/20110708110548/http://www.c4isrjournal.com/story.php?F=2416333 |archive-date=8 July 2011 }}</ref> China and Pakistan also signed a [[memorandum of understanding]] (MoU) for the joint development of AEW&C systems.<ref>{{cite news |last1=Klasra |first1=Rauf |title=$278m AWACS deal struck with China |url=http://www.thenews.com.pk/top_story_detail.asp?Id=19041 |work=The News International |date=18 December 2008 |archive-url=https://web.archive.org/web/20081218180612/http://www.thenews.com.pk/top_story_detail.asp?Id=19041 |archive-date=18 December 2008}}</ref>

The [[Hellenic Air Force]], [[Brazilian Air Force]] and [[Mexican Air Force]] use the [[Embraer R-99]] with an [[Ericsson]] Erieye PS-890 radar, as on the S 100D.<ref>Hellenic Air Force: [http://www.haf.gr/en/mission/weapons/emb-145.asp Embraer EMB-145H AEW&C] {{Webarchive|url=https://web.archive.org/web/20090428095322/http://www.haf.gr/en/mission/weapons/emb-145.asp |date=28 April 2009 }}</ref><ref>{{cite web|url=http://news.cision.com/saab/r/saab-receives-order-for-upgrade-of-mission-system-erieye-for-brazil,c9378232|title=Saab receives order for upgrade of mission system Erieye for Brazil|work=News Powered by Cision|access-date=1 February 2016|archive-url=https://web.archive.org/web/20160223065035/http://news.cision.com/saab/r/saab-receives-order-for-upgrade-of-mission-system-erieye-for-brazil,c9378232|archive-date=23 February 2016|url-status=live}}</ref><ref>{{cite web |last1=Barreira |first1=Victor |title=Brazil seeks first modernised AEW&C aircraft in 2020 |url=https://www.janes.com/article/88475/brazil-seeks-first-modernised-aew-c-aircraft-in-2020 |website=Jane's 360 |access-date=14 May 2019 |archive-url=https://web.archive.org/web/20190513184615/https://www.janes.com/article/88475/brazil-seeks-first-modernised-aew-c-aircraft-in-2020 |archive-date=13 May 2019 |location=Rio de Janeiro |date=13 May 2019 |url-status=live }}</ref>

===Others===
Israel has developed the IAI/Elta [[EL/M-2075]] Phalcon system, which uses an AESA ([[active electronically scanned array]]) in lieu of a rotodome antenna. The system was the first such system to enter service. The original [[EL/M-2075|Phalcon]] was mounted on a [[Boeing 707]]<ref name="B707 Phalcon, Israeli Weapons.com">{{cite web|url=http://www.israeli-weapons.com/weapons/aircraft/phalcon/Phalcon.html |title=B707 Phalcon, "Israeli Weapons.com" |publisher=Israeli-weapons.com |access-date=2012-03-31}}</ref> and developed for the Israeli Defense Force and for export. Israel uses [[IAI EL/W-2085]] airborne early warning and control multi-band radar system on [[Gulfstream G550]]; this platform is considered to be both more capable and less expensive to operate than the older Boeing 707-based Phalcon fleet.<ref>{{Cite news| first = Arie| last = Egozi | title = Israeli air force showcases G550 surveillance fleet | work = [[Flight International]] | url=http://www.flightglobal.com/articles/2010/03/23/339637/israeli-air-force-showcases-g550-surveillance-fleet.html | date = 23 March 2010 | access-date = 8 August 2010}}</ref> North Korea appears to operate an AEW&C plane based on the Il-76.<ref name=Trevithick /> North korean designation and design details are unclear.<ref name=Trevithick>{{cite news |last=Trevithick |first=Joseph |date=27 March 2025 |title=First North Korean Airborne Early Warning Jet Flies, Kim Shows Off Interior |url=https://www.twz.com/air/first-north-korean-airborne-early-warning-jet-flies-kim-shows-off-interior |work=The War Zone |location= |publisher=Recurrent Ventures. |access-date=28 March 2025}}</ref>

==Helicopter AEW systems==
[[File:Royal Navy AEW Seaking Helicopter from 849 Naval Air Squadron MOD (cropped).jpg|left|thumb|An AEW [[Westland Sea King]] helicopter of the [[Royal Navy]]]]

On 3 June 1957, the first of 2 HR2S-1W, a derivative of the [[Sikorsky CH-37 Mojave]], was delivered to the US Navy, it used the [[AN/APS-32]] but proved unreliable due to vibration.<ref>{{Cite web|url=https://www.sikorskyarchives.com/S+56%20HR2S-1H-37.php|title=Sikorsky Archives &#124; S-56/HR2S-1/H-37 Helicopter}}</ref>

The British [[Westland Sea King|Sea King ASaC7]] naval helicopter was operated from both the {{sclass|Invincible|aircraft carrier}}s and later the helicopter carrier {{HMS|Ocean|L12|6}}. The creation of Sea King ASaC7, and earlier AEW.2 and AEW.5 models, came as the consequence of lessons learnt by the Royal Navy during the 1982 [[Falklands War]] when the lack of AEW coverage for the task force was a major tactical handicap, and rendered them vulnerable to low-level attack.<ref name = 'Armistead 131'>Armistead and Armistead 2002, p. 131.</ref> The Sea King was determined to be both more practical and responsive than the proposed alternative of relying on the RAF's land-based [[Avro Shackleton|Shackleton]] AEW.2 fleet. The first examples were a pair of Sea King HAS2s that had the [[Thorn-EMI]] ARI 5980/3 [[Searchwater (radar)|Searchwater LAST radar]] attached to the fuselage on a swivel arm and protected by an inflatable dome.<ref name = 'Armistead 131'/> The improved Sea King ASaC7 featured the Searchwater 2000AEW radar, which was capable of simultaneously tracking up to 400 targets, instead of an earlier limit of 250 targets.<ref>[http://articles.janes.com/articles/jdu2002/Cerberus-set-for-service-aboard-Sea-King-Whiskey.html "Cerberus set for service aboard Sea King Whiskey, Upgrade Update."] {{webarchive|url=http://archive.wikiwix.com/cache/20110708063750/http://articles.janes.com/articles/jdu2002/Cerberus-set-for-service-aboard-Sea-King-Whiskey.html |date=8 July 2011 }} ''Jane's International Defence Review'', 24 September 2002. Retrieved 19 April 2012.</ref><ref name ='Armistead 132-134'>Armistead and Armistead 2002, pp. 132–134.</ref> The [[Spanish Navy]] fields the [[SH-3 Sea King]] in the same role, operated from the LPH {{ship|Spanish amphibious assault ship|Juan Carlos I||2}}. {{Citation needed|date=April 2021}}

The [[AgustaWestland AW101|AgustaWestland EH-101A AEW]] of the [[Italian Navy]] is operated from the aircraft carriers {{ship|Italian aircraft carrier|Cavour||2}} and {{ship|Italian aircraft carrier|Giuseppe Garibaldi||2}}.<ref name="difesa">{{cite web |title=EH – 101 |url=https://www.difesa.it/SGD-DNA/Staff/DT/ARMAEREO/Programmi/Ala-Rotante/Pagine/EH101.aspx |publisher=Italian Ministry of Defense |access-date=29 May 2020}}</ref> During the 2010s, the Royal Navy opted to replace its Sea Kings with a modular "Crowsnest" system that can be fitted to any of their Merlin HM2 fleet.<ref>{{cite web | url=https://www.flightglobal.com/news/articles/thales-bags-selection-for-rn-crowsnest-system-412700/ | title=Thales bags selection for RN Crowsnest system | date=22 May 2015 | first=Craig | last=Hoyle | publisher=Flight Global}}</ref><ref>{{cite web |url=http://www.janes.com/article/37615/uk-extends-sea-king-asac-7-life-out-to-2018 |title=Janes &#124; Latest defence and security news |access-date=17 June 2014 |url-status=live |archive-url=https://web.archive.org/web/20140529145845/http://www.janes.com/article/37615/uk-extends-sea-king-asac-7-life-out-to-2018 |archive-date=29 May 2014 |df=dmy-all }}</ref> The Crowsnest system was partially based upon the Sea King ASaC7's equipment; an unsuccessful bid by Lockheed Martin had proposed using a new multi-functional sensor for either the AW101 or another aircraft.<ref>{{cite web |first= Craig |last= Hoyle |url= http://www.flightglobal.com/news/articles/dsei-thales-outlines-sea-king-7-replacement-proposal-362116/ |title= Thales outlines Sea King 7 replacement proposal |work= Flight International |date= 15 September 2011 |access-date= 5 January 2012 |archive-url= https://web.archive.org/web/20111211012450/http://www.flightglobal.com/news/articles/dsei-thales-outlines-sea-king-7-replacement-proposal-362116/ |archive-date= 11 December 2011 |url-status= live}}</ref><ref>{{cite web |url=https://www.gov.uk/government/news/new-surveillance-system-for-future-royal-navy-aircraft-carriers-revealed |title=New surveillance system for future Royal Navy aircraft carriers revealed |work=gov.uk |access-date=23 July 2015 |archive-url=https://web.archive.org/web/20150717211148/https://www.gov.uk/government/news/new-surveillance-system-for-future-royal-navy-aircraft-carriers-revealed |archive-date=17 July 2015 |url-status=live}}</ref>

The Russian-built [[Kamov Ka-31]] is deployed by the [[Indian Navy]] on the aircraft carriers {{INS|Vikramaditya}} and {{INS|Vikrant|2013|6}} and also on {{sclass|Talwar|frigate|1}}s.<ref>{{cite news|title=Ka-31 Radar Picket Airborne Early Warning (AEW) Helicopter, Russia|newspaper=Airforce Technology |url=http://www.airforce-technology.com/projects/ka31/|publisher=Airforce-technology|access-date=3 January 2014}}</ref> The Russian Navy has two Ka-31R variants, at least one of which was deployed on their aircraft carrier {{ship|Russian aircraft carrier|Admiral Kuznetsov||2}} in 2016.<ref>{{citation | url=http://www.combataircraft.net/2016/10/21/carrier-based-ka-52k-bound-for-syria/ | title=Carrier-based Ka-52K bound for Syria | journal=Combat Aircraft | date=21 October 2016 | access-date=15 November 2016 | archive-date=16 November 2016 | archive-url=https://web.archive.org/web/20161116102930/http://www.combataircraft.net/2016/10/21/carrier-based-ka-52k-bound-for-syria/ | url-status=dead }}</ref> It is fitted with E-801M Oko (Eye) airborne electronic warfare radar that can track 20 targets simultaneously, detecting aircraft up to {{convert|150|km|abbr=on|-1}} away, and surface warships up to {{convert|200|km|abbr=on}} distant.

==See also==
<!--links to specific aew systems should be included in text and not here-->
* [[List of airborne early warning aircraft]]
* [[List of AEW&C aircraft operators]]
* [[Airborne ground surveillance]] (e.g. [[JSTARS]])

==References==
===Citations===
{{reflist}}

===Bibliography===
* Armistead, Leigh and Edwin Armistead. ''Awacs and Hawkeyes: The Complete History of Airborne Early Warning Aircraft''. St Paul, Minnesota: Zenith Imprint, 2002. {{ISBN|0-7603-1140-4}}.
* {{Cite magazine |last=Davies |first=Ed |title=AWACS Origins: Brassboard – Quest for the E-3 Radar |magazine=[[Air Enthusiast]] |issue=119, September/October 2005 |location=Stamford, Lincs, UK |publisher=Key Publishing |issn=0143-5450 |pages=2–6}}
* {{Cite book |last1=Gibson |first1=Chris |title=The Admiralty and AEW: Royal Navy Airborne Early Warning Projects|publisher=Blue Envoy Press |year=2011 |isbn=978-0956195128}}
* {{Cite book |last1=Gordon |first1=Yefim |last2=Komissarov |first2=Dmitriy |title=Soviet/Russian AWACS Aircraft: Tu-126, A-50, An-71, Ka-31 |series=Red Star Vol. 23 |publisher=Midland Publishing |location=Hinckley, England |year=2010 |isbn=978-1857802153}}
* {{Cite book |last1=Gordon |first1=Yefim |last2=Davison |first2=Peter |title=Tupolev Tu-95 Bear |series=Warbird Tech |volume=43 |publisher=Specialty Press |location=North Branch, Minnesota |year=2006 |isbn=978-1-58007-102-4}}
* {{Cite book |last1=Hazell |first1=Steve |title=Fairey Gannet |series=Warpaint Series No.23 |publisher=Hall Park Books |location=Buckinghamshire, England |year=2000 |issn=1363-0369}}
* {{Cite book |last=Hirst |first=Mike |title=Airborne Early Warning: Design, Development, and Operations |location=London |publisher=Osprey |year=1983 |isbn=978-0-85045-532-8}}
* {{Cite book |last=Hurturk |first=Kivanc N. |title=History of the Boeing 707 |location=New Hills |publisher=Buchair |year=1998 |isbn=0-9666368-0-5}}
* {{Cite magazine |last=Lake |first=Jon |title=Aircraft of the RAF – Part 10 Sentry AEW.1 |magazine=[[Air International]] |issue= 2 |date = February 2009 |volume=76 |location=Stamford, UK |publisher=Key Publishing |pages=44–47}}
* {{Cite book |last1=Lloyd |first1=Alwyn T. |title=Boeing 707 & AWACS |series=in Detail and Scale |publisher=Aero Publishers |location=Falbrook, CA |year=1987 |isbn=0-8306-8533-2}}
* {{Cite book |last1=Neufeld |first1=Jacob |last2=Watson |first2=George M. Jr. |last3=Chenoweth |first3=David |title=Technology and the Air Force. A Retrospective Assessment |publisher=United States Air Force |location=Washington, D.C. |year=1997 |pages=267–287}} http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA440094&Location=U2&doc=GetTRDoc.pdf{{Webarchive|url=https://web.archive.org/web/20121007221217/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA440094&Location=U2&doc=GetTRDoc.pdf |date=7 October 2012 }}
* {{Cite book |last=Pither |first=Tony |title=The Boeing 707 720 and C-135 |publisher=Air-Britain (Historians) |year=1998 |isbn=0-85130-236-X}}
* Tyack, Bill "Maritime Patrol in the Piston Engine Era" ''Royal Air Force Historical Society Journal'' '''33''', 2005 {{issn|1361-4231}}.
* {{Cite book |last=Wilson |first=Stewart |title=Boeing 707, Douglas DC-8, and Vickers VC-10 |location=Fyshwick, Australia |publisher=Aerospace Publications |year=1998 |isbn=1-875671-36-6 }}

==External links==
{{Commons category}}
* [https://web.archive.org/web/20121007221217/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA440094&Location=U2&doc=GetTRDoc.pdf AWACS and JSTARS]
* [https://web.archive.org/web/20150801004632/http://awacs-spotter.nl/ NATO AWACS-Spotter Geilenkirchen website]
* [http://www.fas.org/man/dod-101/sys/ac/e-3.htm FAS.org E-3 Sentry information]
* [https://web.archive.org/web/20080218070817/http://www.boeing.com/defense-space/infoelect/awacs/index.html Boeing AWACS website]
* [http://www.aewa.org Airborne Early Warning Association website]
* [https://web.archive.org/web/20110903192613/http://legion.wplus.net/guide/air/m/tu126.shtml TU-126 MOSS AWACS – history of development]- in Russian
* [http://hist.rloc.ru/lobanov/3_01.htm Airborne radar "Gneis-2"] – in Russian
*{{cite web|title=Electronic Weapons: AWACS Then And Forever|url=https://www.strategypage.com/htmw/htecm/articles/20180228.aspx|website=strategypage.com}}

{{Military aircraft types (roles)}}

{{Authority control}}

[[Category:Military aviation]]
[[Category:Early warning systems]]
[[Category:Military electronics]]
[[Category:Military terminology]]
[[Category:Aircraft radars]]