View source for Silkworm (missile)

{{short description|Series of Chinese anti-ship missiles}}
{{Infobox weapon
| name               = SY/HY missiles
| image              = File:SY-1 Missile 20170919.jpg
| image_size         = 300
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| caption            = SY-1 missile
| type               = Anti-ship cruise missile
| origin             = [[China]]
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*[[Hongdu|Nanchang Aircraft Manufacturing Company]] (Now [[Hongdu]]){{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
*[[China Aerospace Science and Industry Corporation]] Third Academy{{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
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The '''SY''' ({{zh|c=上游|p=Shàngyóu|l=Upstream}}), and '''HY''' ({{zh|c=海鹰|p=Hǎiyīng|l=Sea Eagle}}) series were early [[anti-ship missile|anti-ship cruise missile]]s (ASCM) developed by the [[People's Republic of China]] from the [[Soviet Union|Soviet]] [[P-15 Termit]] missile. They entered service in the late 1960s{{sfn|Gormley|Erickson|Yuan|2014b|p=9}} and remained the main ASCMs deployed by the [[People's Liberation Army Navy]] through the 1980s. The missiles were used by the PRC and export customers to develop [[land-attack missile]]s.{{sfn|Gormley|Erickson|Yuan|2014b|p=28}}

The name '''Silkworm''' is popularly used for the entire SY and HY family. As a [[NATO reporting name]], it applies only to the land-based variant of the HY-1.{{sfn|Gormley|Erickson|Yuan|2014b|p=135}}

==Development==
[[File:HY-2 Missile 20170902.jpg|thumb|HY-2 missile]]
[[File:HY-3 Missile 20170919.jpg|thumb|HY-3 missile]]
Chinese preparations were underway before receiving the first P-15s and related technical data from the Soviets in 1959. On 8 October 1956, the [[China Aerospace Science and Technology Corporation|Fifth Academy]] was founded - with [[Qian Xuesen]] as director - to pursue missile development. In March 1958 a cruise missile test site was selected at [[Liaoxi]] in [[Liaoning]].{{sfn|Gormley|Erickson|Yuan|2014b|p=9}}

In November 1960, the first successful missile test was conducted after the withdrawal of Soviet advisors in September, due to the [[Sino-Soviet split]]. The P-15 was copied to become the SY-1. In October 1963, production started at the [[Hongdu|Nanchang Aircraft Manufacturing Company]]. In 1965, the first successful test occurred. In August 1967, production was approved.  The SY-1 entered service by the end of the decade.{{sfn|Gormley|Erickson|Yuan|2014b|p=9}}

The SY-1 was developed into the improved HY-1. In December 1968, the HY-1 was successfully tested, and entered service in 1974.{{sfn|Gormley|Erickson|Yuan|2014b|pp=9-10}}

==Operational history==

===Iran–Iraq War===
The Silkworm gained fame in the 1980s when it was used by both sides in the [[Iran–Iraq War]]. Both countries were supplied by China. In 1987, Iran launched a number of Silkworm missiles from the [[Faw Peninsula]], striking the American-owned, [[Liberia]]n-flagged tanker ''Sungari'' and the U.S.-flagged tanker [[MV Sea Isle City|''Sea Isle City'']] in October 1987.<ref>[https://query.nytimes.com/gst/fullpage.html?res=9B0DE5DA1138F934A25753C1A961948260 "U.S. Flag Tanker Struck by Missile in Kuwaiti Waters; First Direct Raid"]. ''[[The New York Times]]''. October 17, 1987.</ref> Five other missiles struck areas in Kuwait earlier in the year.<ref>[https://web.archive.org/web/20121025161818/http://www.time.com/time/magazine/article/0,9171,965887-1,00.html "The Gulf Punch, Counterpunch]". ''[[Time (magazine)|Time]]''.</ref>

In October 1987, Kuwait's Sea Island offshore [[oil terminal]] was hit by an Iranian Silkworm, which was observed to have originated from the Faw peninsula. The attack prompted Kuwait to deploy a [[MIM-23 Hawk|Hawk missile]] battery on [[Failaka Island]] to protect the terminal.<ref>[https://web.archive.org/web/20121025161818/http://www.time.com/time/magazine/article/0,9171,965887-1,00.html "The Gulf Punch, Counterpunch]". ''[[Time (magazine)|Time]]''.</ref> In December 1987, another Iranian Silkworm was fired at the terminal, but it struck a decoy barge instead.<ref>"Iranian Silkworm strikes decoy barge"; Daniel J. Silva. ''[[St. Petersburg Times]]''. St. Petersburg, Fla.: December 8, 1987. p. 14.A.</ref> 

Prior to these attacks the missile's range was thought to be less than {{convert|80|km|mi}}, but these attacks proved that the range exceeded {{convert|100|km|mi}} with [[military of Kuwait|Kuwaiti military]] observers seeing that the missiles originated from the area and tracking them on radar along with US satellite imagery of the launch sites.<ref name=ICJ>[http://www.icj-cij.org/docket/files/90/8632.pdf Counter-memorial and Counter-claim submitted by the United States of America] {{webarchive|url=https://web.archive.org/web/20140331230923/http://www.icj-cij.org/docket/files/90/8632.pdf |date=2014-03-31 }}. June 23, 1997.</ref>

===Persian Gulf War===
On February 25, 1991 during [[Operation Desert Storm]], a shore-based Iraqi launcher fired two Silkworm missiles at the [[USS Missouri (BB-63)|USS ''Missouri'']] which was in company with the [[USS Jarrett (FFG-33)|USS ''Jarrett'']] and [[HMS Gloucester (D96)|HMS ''Gloucester'']]. A [[Sea Dart missile]] from HMS ''Gloucester'' shot down one Silkworm and the other missed, crashing into the ocean.<ref name="friendly fire I">{{cite web |url=http://www.gulflink.osd.mil/du_ii/du_ii_tabh.htm |title=TAB H &ndash; Friendly-fire Incidents |access-date=2007-02-25 |last=Rostker |first=Bernard |date=December 2000 |work=Depleted Uranium in the Gulf (II) |publisher=United States Department of Defense |archive-date=2013-06-01 |archive-url=https://web.archive.org/web/20130601053948/http://www.gulflink.osd.mil/du_ii/du_ii_tabh.htm |url-status=dead }}</ref> [[Royal Air Force]] officers subsequently recovered an HY-2 missile at [[Umm Qasr]] in southern Iraq. It is currently displayed at the [[Royal Air Force Museum Midlands]].<ref>{{cite web | url=http://www.rafmuseum.org.uk/research/collections/hai-ying-2g-silkworm/ | title=Hai Ying 2G Seersucker | publisher=RAF Museum | access-date=17 May 2014}}</ref>

===Iraq War===
During the [[2003 invasion of Iraq]], [[Iraq]] used the Silkworm (HY-2 Seersucker) as a [[surface to surface missile]], by firing at least two of them at the coalition positions in [[Kuwait]].<ref>{{Cite web|url=https://www.pogo.org/center-for-defense-information/|archive-url=https://web.archive.org/web/20031223155156/http://www.cdi.org/friendlyversion/printversion.cfm?documentID=1799|url-status=dead|title=Center for Defense Information|archive-date=December 23, 2003|website=Project On Government Oversight}}</ref>

=== Blockade of Yemen ===
On 12 October 2016, during the [[Blockade of Yemen]], two Silkworm missiles were fired from the Houthi-controlled port of [[Al Hudaydah]] at the destroyer {{USS|Mason|DDG-87|6}} operating in the [[Bab el-Mandeb]] strait. Both impacted the sea, possibly due to the countermeasures.<ref name="u4023">{{cite web |date=2016-10-12 |title=Official: Yemen rebels fire 2 missiles at Navy ship, U.S. responds with strikes |url=https://www.cbsnews.com/news/official-yemen-rebels-fire-2-missiles-at-navy-ship-us-responds-with-strikes/ |access-date=2025-01-12 |website=CBS News}}</ref><ref name="2nd attack">{{Cite web |last=LaGrone |first=Sam |date=12 October 2016 |title=Pentagon Pledges to Respond in 'Appropriate Manner' After New Yemen Missile Attack on USS Mason |url=https://news.usni.org/2016/10/12/pentagon-respond-appropriate-manner-new-missile-attack-uss-mason-yemen |access-date=12 October 2016 |website=USNI News |publisher=U.S. Naval Institute}}</ref>

==Variants==
===SY series===
;SY-1
:License produced version of the P-15 Termit.{{sfn|Gormley|Erickson|Yuan|2014b|p=9}} NATO reporting name '''CSS-N-1 Scrubbrush'''.{{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
;SY-2{{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
:NATO reporting names '''CSS-N-5 Sabot'''. The SY-2 is a significant redesign of the SY-1 missile and is no longer a copy of the P-15. The missile has a longer airframe and is powered by a solid propellant rocket motor, instead of the liquid propellant design from the Styx. The SY-2 otherwise shares launchers and support equipment with the SY-1 (P-15), however, and eventually replaced the old missiles on unmodernized Jianghu class frigates.<ref name="ausairpower_sy2">{{cite journal|last1=Kopp |first1=Carlo |last2=Andrew |first2=Martin |url=https://www.ausairpower.net/APA-PLA-Cruise-Missiles.html#mozTocId500709 |title=HAIC SY-2/SY-2A/FL-2 / CSS-N-5 Sabot |website=ausairpower.net |date=12 August 2009 |pages=1 }}</ref>
;SY-2A
:An improved SY-2 with a longer range.<ref name="ausairpower_sy2" />
;FL-2
:The export version of the SY-2.<ref name="ausairpower_sy2" />

===HY series===
;HY-1
:NATO reporting names '''CSS-N-2 Safflower''' (ship-based) and '''CSSC-2 Silkworm''' (land-based.){{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
;HY-2
:NATO reporting names '''CSS-N-3 Seersucker''' (ship-based) and '''CSSC-3 Seersucker''' (land-based.){{sfn|Gormley|Erickson|Yuan|2014b|p=113}}
;HY-3
:Unsuccessful supersonic variant.{{sfn|Gormley|Erickson|Yuan|2014a|p=102}}
;HY-4
:Powered by a WP-11 [[turbojet]], a reverse-engineered [[Teledyne CAE J69|Teledyne-Ryan J69-T-41A]].{{sfn|Gormley|Erickson|Yuan|2014b|p=29}} Used for LACM development.{{sfn|Gormley|Erickson|Yuan|2014b|p=27}} NATO reporting name '''Sadsack'''.{{sfn|Gormley|Erickson|Yuan|2014b|p=84}}
;HY-41
:An improved HY-4.<ref name="ausairpower_hy41">{{cite journal|last1=Kopp |first1=Carlo |last2=Andrew |first2=Martin |url=https://www.ausairpower.net/APA-PLA-Cruise-Missiles.html#mozTocId411792 |title=CHETA C-201W / HY-4/HY-4A/G / HY-41 / CSS-C-7 Sadsack |website=ausairpower.net |date=12 August 2009 |pages=1 }}</ref>
;C-201
:An export version of the HY-2.{{sfn|Gormley|Erickson|Yuan|2014a|p=102}}
;C-301
:An export version of the HY-3.{{sfn|Gormley|Erickson|Yuan|2014a|p=105}}
;C-201W
:An export version of the HY-4.{{sfn|Gormley|Erickson|Yuan|2014a|p=102}}
;XM-41
:An export version of the HY-41.<ref name="ausairpower_hy41" />

===Further development===
;[[YJ-6]]
:Anti-ship missile developed from the HY-2.
;YJ-63
:Air-launched LACM sharing visual characteristics of the HY-2, HY-4, and YJ-6. 200&nbsp;km range.{{sfn|Gormley|Erickson|Yuan|2014b|p=29}}
;AG-1
:Longer-ranged variant of the HY-2 developed by [[North Korea]].<ref>{{cite web |title=KN-01 (Silkworm/Styx) |url=https://missilethreat.csis.org/missile/kn-01/ |date=31 July 2021 |website=Missile Threat |publisher=Center for Strategic and International Studies |access-date=7 July 2022}}</ref>

==Operators==

; {{CHN}}
* {{Navy|China}}
; {{IRN}}
* {{Navy|Iran}}
; {{flag|Iraq|1991}}
* {{Navy|Iraq}}
; {{PRK}}
* {{Navy|North Korea}}

==References==
{{reflist|30em}}

===Sources===
{{Refbegin}}
*{{cite journal |last1=Gormley |first1=Dennis M. |last2=Erickson |first2=Andrew S. |last3=Yuan |first3=Jingdong |date=30 September 2014a |title=A Potent Vector: Assessing Chinese Cruise Missile Developments |url=http://ndupress.ndu.edu/Media/News/NewsArticleView/tabid/7849/Article/577568/jfq-75-a-potent-vector-assessing-chinese-cruise-missile-developments.aspx |journal=Joint Forces Quarterly |publisher=[[National Defense University (Washington, D.C.)|National Defense University]] |issue=75}}
*{{cite report |last1=Gormley |first1=Dennis M. |last2=Erickson |first2=Andrew S. |last3=Yuan |first3=Jingdong |date=2014b |title=A Low-Visibility Force Multiplier: Assessing China's Cruise Missile Ambitions |url=http://ndupress.ndu.edu/Portals/68/Documents/Books/force-multiplier.pdf |location=Washington, D.C. |publisher=[[National Defense University (Washington, D.C.)|National Defense University]] Press}}
{{Refend}}

==External links==
{{Commons category multi|SY-1 Shangyou|HY-1 Haiying|HY-2 Haiying}}
* [https://web.archive.org/web/20160107013517/http://www.fas.org/man/dod-101/sys/missile/row/hy-1.htm Federation of American Scientists page on HY-1]
* [https://web.archive.org/web/20160113063345/https://fas.org/man/dod-101/sys/missile/row/c-201.htm Federation of American Scientists page on HY-2]

{{Chinese Missiles}}{{DPRK missiles}}
[[Category:Anti-ship cruise missiles of the People's Republic of China]]
[[Category:China–Soviet Union relations]]
[[Category:Guided missiles of the People's Republic of China]]
[[Category:Surface-to-surface missiles of China]]