Since 1994, when China introduced the HQ-6, a mobile anti-aircraft system, the Chinese air defense system has gone from 1940s tech to stuff that is competitive with the best in the West. For decades China has depended on a large force of anti-aircraft guns for much of their air defense. A decade ago this consisted of 30 battalions of anti-aircraft guns (about 50 guns each). These were mainly what was called “flack” during World War II, For China this meant twin 23mm guns or 57mm guns, plus single 85mm or 100mm guns and some weapons of other calibers. All these were radar controlled. In addition there was an anti-aircraft militia equipped with some 1,500 battalions of guns. That was over 70,000 anti-aircraft guns that were not in the best shape, and most were quite old. The crews were poorly trained reservists and didn’t get much practice with live ammunition. However, if there were a war, most of these guns would be manned, and better trained, in a few weeks. However a lot of the ammo reserves were very old so a lot of the shells would be duds or malfunction in ways that could injure the gun crews. Most of this stuff is gone now, replaced by a growing number of short range anti-aircraft missile systems. HQ-6 was one of the first.
HQ-6 is a ground-to-air version of the PL-11 air-to-air missile. The HQ-6 missile weighs 220 kg (484 pounds) with a 33 kg warhead. Range is 18 kilometers. An HQ-6 battery consists of one long range search radar and three tracking/fire control radars. There are six launcher vehicles each with two (later four) missiles. The latest version, the HQ-6D, adds a command vehicle which can network with and control up to four HQ-6 batteries. The command vehicle also has the communication gear and software that allows it to link to an even larger air defense network. Because of its longer range (4-5 times that of guns) fewer HQ-6 launchers are needed compared to the guns.