Description: The HHQ-9A is a shipborne air defense system introduced by Chinese People's Liberation Army Navy (PLAN) on the Type 052C destroyer in 2004. The system is based on the HQ-9A mobile air defense system fielded by the People's Liberation Army beginning in 1997. The HHQ-9A ship-mounted phased array radar antennas look like the SPY-1 antennas installed on the US Navy Aegis-equipped destroyers and cruisers. The HHQ-9A can track as many as 100 airborne targets while engaging 50 of them simultaneously.
The HHQ-9A missile system provided to Type 052C destroyers has eight six-cell Vertical Launch Systems (VLS) with six of them at the bow deck and the remaining two at the stern. The Chinese designed VLS features a cylindrical shape and "cold launch" in comparison with Western VLS such as Mk-41 and Sylver which are rectangular and use "hot launch". The main difference between cold and hot launches is that the rocket motor ignites out or in the launch tube. The Chinese VLS is neither based upon the Russian revolver launch system also featuring six-cell.
The HHQ-9A surface-to-air missile guidance system responds to the Track-Via-Missile (TVM) concept introduced by the United States with its Patriot missile system. The HQ-9 missile's seeker target data is transmitted to the control station via downlink. The ground control station calculates the trajectory corrections to enable a successful interception and those corrections are sent back to the HQ-9 missile via an uplink.