OVERVIEW:  The HY-2 aka Haiying-2 aka C-201 aka CSSC-3 SEERSUCKER battalion is a semi-mobile, medium-range, ASCM equipped coastal defense unit.

DETAILS: 

During launch, the missile is initially boosted to an altitude of 145 meters by a solid fuel rocket booster.  From there, it is powered by a liquid fuel sustainer and descends to 30 meters, using inertial guidance to fly to the target area.  At approximately 10 km from its target, the radar seeker activates and directs the missile towards the strongest radar reflection. The HY-2G is equipped with a radar altimeter, allowing it to decent to only 25 feet during this terminal phase.

The toxic and corrosive AK-20F/TG-02 propellant mix necessitates the use of chemical suits, a major operational encumbrance for this family of missiles.

Although obsolete by the 1990's, the missile remained strategically important for some time, due to its lethality and wide deployment. Used against transports, tankers, amphibious ships and other targets without defensive systems, the missile is highly lethal. Not only does it carry a large warhead, but the unburned hypergolic fuel produces considerable incendiary effect.

Specifications:

Engagement Envelope, range:	107 nm; 200 km  
Kill probability:		0.85
Reload time:			?? minutes (approx)
Reaction Time			?? seconds
Mobility:			semi-mobile

NOTES: IOC: early 1980's. By 1988, the HY-2 was easily jammed or seduced by ECM and decoys.   Exported to Egypt, Iraq, Iran, Albania, Zaire, Pakistan, Bangladesh, Myanmar, and North Korea.  Th HY-2 is frequently misidentified as a "SILKWORM" in press articles. 

SOURCES: C-201 / Hy-2 / Sy-1 / Css-C-3 / Seersucker. (n.d.). https://gulflink.health.mil/kuwaiti_final/kuwaiti_final_refs/n62en007/c_201_seersucker.htm ; DIA. (1988, May 23). A Brief Introduction to the Bandit-Made Silkworm Missile. Defense Intelligence Agency. https://www.dia.mil/FOIA/FOIA-Electronic-Reading-Room/FOIA-Reading-Room-China/FileId/89301/ ; Friedman, N. (1997). The naval institute guide to world naval weapons systems 1997-1998. US Naval Institute Press. ; Kopp, D. C. (n.d.). PLA cruise missiles / PLA air - Surface missiles. Air Power Australia. https://www.ausairpower.net/APA-PLA-Cruise-Missiles.html