Editing Lockheed S-3 Viking (section)

==Operational history==
[[File:S-2G and S-3A in flight 1976.jpg|thumb|S-3A replaced the outdated [[S-2 Tracker]] in 1975]]

On 20 February 1974, the S-3A officially became operational with the [[VS-41|Air Antisubmarine Squadron FORTY-ONE (VS-41)]], the "Shamrocks," at [[NAS North Island]], California, which served as the initial S-3 Fleet Replacement Squadron (FRS) for both the Atlantic and Pacific Fleets until a separate Atlantic Fleet FRS, VS-27, was established in the 1980s. The first operational cruise of the S-3A took place in 1975 with the [[Sea Control Squadron 21|VS-21]] "Fighting Redtails" aboard {{USS|John F. Kennedy|CV-67|6}}.<ref name=":0" />{{self-published inline|certain=y|date=May 2023}}

Initial operations of the Viking were somewhat troubled in the carrier environment, its sophisticated mission systems were largely dependent on the mission computer, which would often "dump" during the stress of a catapult-assisted take-off, requiring the crew to restart it and reload the software.<ref name = "desertwarrior 2009"/> The U.S. Navy had also purchased an insufficient number of spare parts, which negatively impacted the aircraft's mission readiness. Performance improved considerably once an ample supply of spares was provisioned, allowing the S-3 to become a valuable ASW asset as well as a good surface-surveillance platform.<ref name = "desertwarrior 2009">{{cite web |url = https://www.thefreelibrary.com/S-3+Viking%3A+from+sub+hunter+to+desert+warrior.-a0230156116 |title = S-3 Viking: from sub hunter to desert warrior |publisher = Naval Aviation News |first = Rick |last = Burgess |date = 1 November 2009}}</ref>

Starting in 1987, the majority of S-3As were progressively upgraded to the improved ''S-3B'' standard; this involved the addition of several new sensors, avionics, and weapons systems, which included the capability to launch the [[AGM-84 Harpoon]] [[anti-ship missile]].<ref name = "nasaretire ain"/><ref name = "desertwarrior 2009"/> The S-3B could also be fitted with "[[buddy store]]s", external fuel tanks that allowed the Viking to refuel other aircraft. During July 1988, VS-30 became the first fleet squadron to receive the enhanced capability Harpoon/ISAR equipped S-3B, based at [[Naval Air Station Cecil Field|NAS Cecil Field]] in [[Jacksonville, Florida]].

Additional, often more specialised variants, were also produced. 16 S-3As were converted to ''ES-3A Shadow''s for carrier-based [[ELINT|electronic intelligence]] (ELINT) duties. Six aircraft, designated ''US-3A'', were converted for a specialized utility and limited cargo [[Carrier onboard delivery]] (COD) requirement.<ref name = "nasaretire ain"/> This model played a key role in US military efforts to relieve the [[Iran hostage crisis]] of 1979–1981.<ref name = "desertwarrior 2009"/> Plans were also made to develop the ''KS-3A'' carrier-based [[Tanker (aircraft)|tanker]] aircraft, but this program was ultimately cancelled after the conversion of just one early development S-3A.<ref name="ai786 p44-5">''Air International'' July 1986, pp. 44–45.</ref>

As a consequence of the collapse of the [[Soviet Union]] and the breakup of the [[Warsaw Pact]] in the early 1990s, the Soviet-Russian submarine threat was perceived as much reduced, and the Vikings had the majority of their [[antisubmarine warfare]] equipment removed. The aircraft's mission subsequently changed to sea surface search, sea and ground attack, over-the-horizon targeting, and aircraft refueling.<ref name="gvg" /><ref name = "nasaretire ain"/> As a result, the S-3B after 1997 was typically crewed by a single pilot along with a copilot [NFO]; the additional seats remained in place in the S-3B and could be used by additional crew members for certain missions. To reflect these new missions, the Viking squadrons were redesignated from "Air Antisubmarine Warfare Squadrons" to "Sea Control Squadrons".<ref name = "desertwarrior 2009"/>

[[File:S-3A VS-32 1982.JPEG|thumb|VS-32 S-3A: During the [[Cold War]], the S-3's main task was [[anti-submarine warfare]]]]
Prior to the aircraft's retirement from front-line fleet use aboard US aircraft carriers, a number of upgrade programs were implemented. These include the Carrier Airborne Inertial Navigation System II (CAINS II) upgrade, which replaced older [[inertial navigation]] hardware with [[ring laser gyroscope]]s with a Honeywell EGI (Enhanced [[GPS]] Inertial Navigation System) and added digital electronic flight instruments (EFI). The Maverick Plus System (MPS) added the capability to employ the [[AGM-65 Maverick|AGM-65E]] laser-guided or AGM-65F infrared-guided air-to-surface missile, and the [[Standoff Land Attack Missile|AGM-84H/K Stand-off Land Attack Missile Expanded Response]] (SLAM/ER). The SLAM/ER is a GPS/inertial/infrared guided cruise missile derived from the AGM-84 Harpoon that can be controlled by the aircrew in the terminal phase of flight if an AWW-13 data link pod is carried by the aircraft.<ref name="gvg" />

The S-3B saw extensive service during the 1991 [[Gulf War]], performing attack, tanker, and ELINT duties, and launching [[ADM-141 TALD]] decoys. One such aircraft, launched from the aircraft carrier {{USS|Theodore Roosevelt|CVN-71}}, was responsible for the destruction of an Iraqi [[Silkworm missile|Silkworm]] anti-ship missile site, having fired AGM-84 SLAM missiles at it.<ref name = "national 2020">{{cite web |url = https://nationalinterest.org/blog/reboot/submarine-killer-why-did-us-navy-retire-its-vaunted-s-3-viking-planes-172905 |title = Submarine Killer: Why Did the U.S. Navy Retire Its Vaunted S-3 Viking Planes? |publisher = nationalinterest.org |first = Sebastien |last = Roblin |date = 19 November 2020}}</ref> It was commonly deployed to hunt for [[Scud missile]] launcher. The Vikings also identified and targeted numerous Iraqi naval vessels, and even destroyed anti-aircraft gun emplacements and coastal radars.<ref name = "national 2020"/><ref name = "desertwarrior 2009"/> The Gulf War was the first event in which the type had been employed overland in offensive air strike capacity.{{Citation needed|date=May 2022}}

The Viking also participated in the [[Yugoslav wars]] in the 1990s, and in [[Operation Enduring Freedom]] in the 2000s. For the latter, the opening phase of the [[War in Afghanistan (2001–2021)|War in Afghanistan]] in October 2001, many Vikings were deployed as tankers to continuously undertake refueling sorties to support various fighters stationed aboard U.S. carriers, giving them the necessary endurance to fly to and from the conflict zone.<ref name = "national 2020"/><ref name = "desertwarrior 2009"/>

===Electronic surveillance===
The first ES-3A was delivered during 1991 and entered front-line service after two years of testing. The U.S. Navy established two squadrons, each equipped with eight ES-3As, stationed in both the Atlantic and Pacific Fleets to provide detachments of typically two aircraft, ten officers, and 55 enlisted aircrew, maintenance and support personnel (which comprised/supported four complete aircrews) to deploying carrier air wings. The Pacific Fleet squadron, [[VQ-5|Fleet Air Reconnaissance Squadron FIVE (VQ-5)]], the "Sea Shadows," was originally based at the former [[Antonio B. Won Pat International Airport|NAS Agana]], Guam but later relocated to [[Naval Air Station North Island|NAS North Island]] in [[San Diego, California]], with the Pacific Fleet S-3 Viking squadrons when NAS Agana closed in 1995 as a result of a 1993 [[Base Realignment and Closure]] (BRAC) decision. The Atlantic Fleet squadron, the [[VQ-6|VQ-6 "Black Ravens]]," were originally based with all Atlantic Fleet S-3 Vikings at the former NAS Cecil Field in Jacksonville, Florida, but later moved to [[Naval Air Station Jacksonville|NAS Jacksonville]], approximately {{convert|10|mi|km}} to the east, when NAS Cecil Field was closed in 1999 as a result of the same 1993 BRAC decision that closed NAS Agana.{{Citation needed|date=May 2022}}

[[File:S-3 Viking in-flight refueling.jpg|thumb|After the [[Grumman A-6 Intruder#KA-6D|KA-6D]] retirement the S-3B became the main aerial refueling aircraft]]
The ES-3A operated primarily with [[carrier battle group]]s, providing organic 'Indications and Warning' support to the group and joint theater commanders. In addition to their warning and reconnaissance roles, and their extraordinarily stable handling characteristics and range, Shadows were a preferred recovery tanker (aircraft that provide refueling for returning aircraft). They were also deployed to active combat zones, seeing use over [[Yugoslavia]] to identify targets, as well as to enforce the [[no-fly zone]] over Iraq.<ref name = "national 2020"/> The Shadows reportedly averaged over 100 flight hours per month while deployed. Excessive utilization caused earlier than expected equipment replacement when Naval aviation funds were limited, making them an easy target for budget-driven decision makers. The type was also deemed by some officials to be too costly to continue operating.<ref name = "desertwarrior 2009"/> In 1999, both ES-3A squadrons and all 16 aircraft were decommissioned and the ES-3A inventory placed in [[Aerospace Maintenance and Regeneration Group]] (AMARG) storage at [[Davis-Monthan AFB]], Arizona.{{Citation needed|date=May 2022}}

===Iraq War===
The S-3 was an active participant in [[Operation Iraqi Freedom]], the US invasion of Iraq; it largely performed intelligence and reconnaissance missions in support of other coalition assets.<ref name = "desertwarrior 2009"/> On one occasion, in March 2003 a single S-3B Viking from Sea Control Squadron 38 (The "Red Griffins"), piloted by Richard McGrath Jr., from the aircraft carrier {{USS|Constellation|CV-64}} successfully executed a time-sensitive strike, firing a laser-guided Maverick missile that neutralized a significant Iraqi naval and leadership target in the port city of [[Basra]], [[Iraq]].<ref name = "national 2020"/> This was the first time an S-3 launched a laser-guided [[Maverick missile]] in combat.<ref name = "desertwarrior 2009"/> As the conflict progressed, S-3s were regularly used as surveillance aircraft, often to identify [[improvised explosive device]]s (IEDs) and the insurgents who planted them.<ref name = "desertwarrior 2009"/>

[[File:Navy One.jpg|thumb|S-3B Viking "Navy One" on {{USS|Abraham Lincoln|CVN-72|6}}, May 2003]]
On 1 May 2003, US President [[George W. Bush]] flew in the co-pilot seat of a [[VS-35 (1990-2005)|VS-35]] Viking from [[NAS North Island]], California, to the aircraft carrier {{USS|Abraham Lincoln|CVN-72|6}} off the California coast; while the carrier was well within range of helicopters, it is believed that the S-3 was used as a means of setting a desired tone.<ref name = "national 2020"/> Aboard the carrier, he delivered his "[[Mission Accomplished speech|Mission Accomplished]]" speech announcing the end of major combat in the [[2003 invasion of Iraq]].<ref name = "national 2020"/> During the flight, the aircraft used the presidential [[callsign]] of "[[Navy One]]". The aircraft that President Bush flew in was retired shortly thereafter and on 15 July 2003 was accepted as an exhibit at the [[National Museum of Naval Aviation]] at [[NAS Pensacola]], Florida.

Between July and December 2008, the [[VS-22]] Checkmates, the last sea control squadron, operated a detachment of four S-3Bs from the [[Al Asad Airbase]] in [[Al Anbar Governorate|Al Anbar Province]], {{convert|180|mi|km}} west of Baghdad. The planes were fitted with [[LANTIRN]] pods and they performed non-traditional intelligence, surveillance, and reconnaissance.<ref name = "national 2020"/> After more than 350 missions, the Checkmates returned to NAS Jacksonville, Florida, on 15 December 2008. The squadron was disestablished on 29 January 2009.<ref name=DID>{{cite news |title = The Final Boat: End of the USN's S-3B Vikings |url = http://www.defenseindustrydaily.com/89m-for-fy-2007-support-of-the-usns-s3b-vikings-02777/ |work = Defense Industry Daily |date = 2 February 2009 |access-date = 3 February 2009 }}</ref>

===Final years and retirement===
[[File:S-3B VX-30 at NAS Jax 2010.jpg|thumb|[[VX-30]]'s S-3B, callsign "Bloodhound 700", in 2010.]]
[[File:NASA Glenn Research Center S-3B.jpg|thumb|S-3B N601NA was operated by [[NASA]] from 2009 to 2021.]]

A proposed airframe known as the [[Common Support Aircraft]] was advanced as a successor to the S-3, [[Northrop Grumman E-2 Hawkeye|E-2]], and [[Grumman C-2 Greyhound|C-2]], but this initiative failed to materialize. In 1998, the U.S. Navy awarded a $40 million contract for Lockheed Martin to perform a full-scale [[Fatigue testing]] of the existing S-3s; these tests, which commenced in June 2001, were aimed at extending the viable service life of each remaining aircraft, which had originally been certified for a structural life of 13,000 flight-hours. It was hoped that this could be extended to as much as 17,750 hours.<ref>{{cite web |url = https://news.lockheedmartin.com/2001-06-28-Lockheed-Martin-Aeronautics-Begins-S-3-Viking-Full-Scale-Fatigue-Testing |title = Lockheed Martin Aeronautics Begins S-3 Viking Full Scale Fatigue Testing |publisher = Lockheed Martins |date = 28 June 2001}}</ref>

The final carrier-based S-3B squadron, VS-22, was decommissioned at NAS Jacksonville on 29 January 2009. Sea Control Wing Atlantic was decommissioned the following day, along with the last S-3s in frontline fleet service.<ref name="Navy Retires S-3B">{{cite web |url = http://www.lockheedmartin.com/news/press_releases/2009/090130ae_s3b-viking-retirement.html |title = U.S. Navy retires last Lockheed Martin S-3B Viking from fleet service |publisher = Lockheed Martin |date = 30 January 2009 |access-date = 21 April 2010 |archive-date = 2 June 2009 |archive-url = https://web.archive.org/web/20090602055342/http://www.lockheedmartin.com/news/press_releases/2009/090130ae_s3b-viking-retirement.html |url-status = dead }} {{Cite web |url=http://www.lockheedmartin.com/news/press_releases/2009/090130ae_s3b-viking-retirement.html |title=U.S. Navy Retires Last Lockheed Martin S-3B Viking from Fleet Service; Carrier-Based Multi-Mission Aircraft Completes 35-Year Career &#124; Lockheed Martin |access-date=5 February 2009 |archive-date=2 June 2009 |archive-url=https://web.archive.org/web/20090602055342/http://www.lockheedmartin.com/news/press_releases/2009/090130ae_s3b-viking-retirement.html |url-status=dead }}</ref><ref name = "desertwarrior 2009"/>

In June 2010, the first of three S-3s to patrol the [[Pacific Missile Test Center]]'s range areas off of California was reactivated and delivered. The jet aircraft's higher speed, ten-hour endurance, modern radar, and a LANTIRN targeting pod allowed it to quickly confirm the test range being clear of wayward ships and aircraft before tests commence.<ref name="S-3B re-enters service at test range">{{cite web |url = http://www.janes.com/news/defence/idr/idr100603_1_n.shtml |title = S-3B Viking re-enters USN service in test range surveillance role |publisher = IHS Jane's |date = 3 June 2010 |access-date = 8 June 2010}}</ref> These S-3Bs are flown by Air Test and Evaluation Squadron Thirty ([[VX-30]]) based out of [[NAS Point Mugu]], California.<ref>{{cite web |url = http://www.navair.navy.mil/index.cfm?fuseaction=home.NAVAIRNewsStory&id=4604 |title = Last S-3B Viking overhauled at FRCSE heads for California-based test squadron |publisher = Naval Air Systems Command (United States Navy) |date = 3 June 2011 |access-date = 23 April 2013 |archive-date = 26 September 2012 |archive-url = https://web.archive.org/web/20120926080000/http://www.navair.navy.mil/index.cfm?fuseaction=home.NAVAIRNewsStory&id=4604 |url-status = dead }}</ref><ref>{{cite web |url = http://www.janes.com/news/defence/idr/idr100603_1_n.shtml |title = S-3B Viking re-enters USN service in test range surveillance role |publisher = Janes.com |access-date = 13 March 2015}}</ref> By late 2015, the U.S. Navy were operating a total of three Vikings in support roles. One was relocated to [[Davis–Monthan Air Force Base|The Boneyard]] in November 2015, while the final two were retired, one being stored and the other transferred to [[NASA]], on 11 January 2016, officially retiring the S-3 from Navy service.<ref name="flightglobal14jan16">{{cite web |url = https://www.flightglobal.com/news/articles/us-navy-retires-its-last-s-3b-vikings-420816/ |title = US Navy retires its last S-3B Vikings |publisher = Flightglobal.com |date = 14 January 2016}}</ref><ref name=Navy_retire>{{cite web |url = http://theaviationist.com/2016/01/14/u-s-navy-bids-farewell-to-the-s-3-viking/ |title = U.S. Navy bids farewell to the S-3 Viking |publisher = theaviationist.com |date = 14 January 2016}}</ref>

During 2004, NASA acquired four of the withdrawn S-3Bs for use at its [[Glenn Research Center]].<ref name = "nasaretire ain">{{cite web |url = https://www.ainonline.com/aviation-news/defense/2021-07-15/nasa-retires-last-flying-s-3-viking |title = NASA Retires Last Flying S-3 Viking |publisher = [[AINonline]] |first = David |last = Donald |date = 14 July 2021}}</ref> In 2009, one of these aircraft (USN BuNo 160607) was given the civil registration ''N601NA'', it was involved in numerous tests conducted by the agency. For over a decade, this aircraft was flying almost every day in support for various research programs;<ref name = "nasaretire ain"/> one such initiative was the definition of new [[Federal Aviation Administration]] communication standards for [[unmanned aerial vehicle]]s operating in US airspace.<ref>{{cite web |url = https://www.ainonline.com/aviation-news/2013-07-05/nasa-tests-prototype-uas-datalink-radio |title = NASA Tests Prototype UAS Datalink Radio |publisher = AINonline |first = Bill |last = Carey |date = 5 July 2013}}</ref> However, a lack of spare parts and increasing difficulty supporting the type meant their use could not continue in the long term. The last of the NASA's S-3Bs, which were the final working members of the type in existence with any operator at that point, were retired on 13 July 2021.<ref>{{cite web |url = https://www.nasa.gov/feature/glenn/2021/NASA-retires-S-3B-Viking-research-aircraft-from-its-fleet/ |title = NASA Retires a Research Workhorse |publisher = NASA |date = 8 July 2021 |access-date = 12 July 2021}}</ref><ref name = "nasaretire ain"/>

Naval analysts have suggested that the U.S. Navy return to service an unspecified quantity of the stored S-3s in order to fill gaps that were left in the carrier air wing when it was retired. This move was promoted as a response to the realization that the [[People's Liberation Army Navy|Chinese navy]] is producing increasingly capable weapons that can threaten carriers beyond the range their aircraft can strike them. Against the [[DF-21#DF-21D (CSS-5 Mod-4) Anti-ship ballistic missile|DF-21D]] [[anti-ship ballistic missile]], carrier-based [[F/A-18 Super Hornet]]s and [[F-35C Lightning II]]s have about half the unrefueled strike range, so bringing the S-3 back to aerial tanking duties would extend their range against it, as well as free up Super Hornets forced into tanking. Against submarines armed with anti-ship cruise missiles like the [[Klub missile|Klub]] and [[YJ-18]], the S-3 would restore area coverage for ASW duties. Bringing the S-3 out of retirement could at least be a stop-gap measure to increase the survivability and capabilities of aircraft carriers until new aircraft can be developed for such purposes.<ref>{{cite web |url = https://thediplomat.com/2015/11/u-s-navy-time-to-bring-back-the-s-3-viking/ |title = U.S. Navy: Time to Bring Back the S-3 Viking? |publisher = Thediplomat.com |date = 9 November 2015}}</ref>

===Potential revival and proposals===
In October 2013, the [[Republic of Korea Navy]] expressed its interest in acquiring up to 18 ex-USN S-3s to augment their fleet of 16 Lockheed P-3 Orion aircraft.<ref>Sung-Ki, Jung [http://archive.defensenews.com/article/20131026/DEFREG03/310260005/S-Korea-Envisions-Light-Aircraft-Carrier "S. Korea envisions light aircraft carrier."] {{webarchive|url=https://archive.today/20150315034643/http://archive.defensenews.com/article/20131026/DEFREG03/310260005/S-Korea-Envisions-Light-Aircraft-Carrier |date=15 March 2015 }} ''Defense News'', 26 October 2013. Retrieved: 13 March 2015.</ref> In August 2015, a military program review group approved a proposal to incorporate 12 mothballed S-3s to perform ASW duties; the Viking plan was sent onto the [[Defense Acquisition Program Administration]] for further assessment before final approval decision by the national defense system committee. Although the planes are relatively old, being in storage has supposedly kept them serviceable, and using them is an affordable means of fulfilling short-range airborne ASW capabilities that were vacated by the retirement of the S-2 Tracker.<ref>{{cite web |url = http://english.yonhapnews.co.kr/national/2015/09/06/0301000000AEN20150906002600320.html |title = S. Korea moving ahead to introduce Viking anti-submarine planes into service |publisher = Yonhapnews.co.kr |date = 9 September 2015}}</ref> Refurbished S-3s could have been returned to use by 2019.<ref name="flightglobal14jan16"/> In 2017, the Republic of Korea Navy canceled plans to purchase refurbished and upgraded Lockheed S-3 Viking aircraft for maritime patrol and anti-submarine duties, leaving offers by Airbus, Boeing, Lockheed Martin, and Saab on the table.<ref>{{cite web |last1 = Perrett |first1 = Bradley |last2 = Kim |first2 = Minseok |title = S. Korea Eyeing P-8, Swordfish As S-3 Upgrade Dropped|url=http://aviationweek.com/awindefense/s-korea-eyeing-p-8-swordfish-s-3-upgrade-dropped |website = Aviation Week |access-date = 19 October 2017 |archive-url = https://archive.today/20171019084626/http://aviationweek.com/awindefense/s-korea-eyeing-p-8-swordfish-s-3-upgrade-dropped |archive-date = 19 October 2017 |location = Melbourne, Australia and Seoul |date = 16 March 2017 |url-status = dead}}</ref><ref>{{cite web |last1 = Waldron |first1 = Greg |title = ADEX: Big MPAs hunt for Seoul maritime requirement |url = https://www.flightglobal.com/news/articles/adex-big-mpas-hunt-for-seoul-maritime-requirement-442267/ |website = FlightGlobal |access-date = 19 October 2017 |archive-url = https://archive.today/20171019084538/https://www.flightglobal.com/news/articles/adex-big-mpas-hunt-for-seoul-maritime-requirement-442267/ |archive-date = 19 October 2017 |location = Seoul |date = 18 October 2017 |url-status = dead}}</ref>

During April 2014, Lockheed Martin announced that they would offer refurbished and remanufactured S-3s, dubbed the ''C-3'', as a replacement for the Northrop [[Grumman C-2A Greyhound]] for [[carrier onboard delivery]]. The requirement for 35 aircraft would be met from the 91 S-3s currently in storage.<ref>{{cite web |last = Cavas |first = Christopher P. |url = http://www.defensenews.com/article/20140409/DEFREG02/304090028/ |title = Lockheed revives an old idea for new carrier cargo plane |publisher = Defense News |date = 9 April 2014 |archive-url=https://archive.today/20150209193642/http://www.defensenews.com/article/20140409/DEFREG02/304090028/ |archive-date=9 February 2015 |url-status=dead}}</ref> In February 2015, the Navy announced that the [[Bell Boeing V-22 Osprey]] had been selected to replace the C-2 for the COD mission.<ref>{{cite web |last = Kreisher |first = Otto |url = http://breakingdefense.com/2015/02/navy-2016-budget-funds-v-22-cod-buy-carrier-refuel/ |title = Navy 2016 budget funds V-22 COD buy, carrier refuel |publisher = Breaking Defense |date = 2 February 2015}}</ref><ref>{{Cite web |url = http://news.usni.org/2015/01/13/navy-selects-bell-boeing-osprey-next-carrier-delivery-aircraft |title = Navy and Marines Sign MOU for Bell-Boeing Osprey to be Next Carrier Delivery Aircraft |publisher = News.USNI.org |date = 13 January 2015}} {{Cite web |url=http://news.usni.org/2015/01/13/navy-selects-bell-boeing-osprey-next-carrier-delivery-aircraft |title=Updated: Navy and Marines Sign MOU for Bell-Boeing Osprey to be Next Carrier Delivery Aircraft |date=13 January 2015 |access-date=23 May 2022 |archive-date=18 January 2015 |archive-url=https://web.archive.org/web/20150118201328/http://news.usni.org/2015/01/13/navy-selects-bell-boeing-osprey-next-carrier-delivery-aircraft |url-status=live}}</ref> A SV-22 was a proposed [[anti-submarine warfare]] variant the U.S. Navy studied in the 1980s to replace S-3 Viking and late model [[Kaman SH-2 Seasprite|SH-2 Seasprite]] ASW helicopters.<ref name="Norton_p28_48">Norton 2004, pp. 28–30, 35, 48.</ref>