The concept of HQ-2B was considered in 1978 as a further improvement on the HQ-2, and the design work officially began in 1979. The PLA requirements for the missile include improved electronic countermeasures capability, expanded operational zone, shortened preparation time, simplified and mobile launch equipment, and the ability to attack high-speed targets. Operational tests and design certification trials took place during 1980~1986, and the missile entered service with the PLA in the early 1990s.
Compared to the basic variant HQ-2, the HQ-2B features some fundamental improvements in its design. The main improvements include:
Missile:
Redesigned fragmental HE warhead and more powerful fuse for increased blast radius;
New improved rocket motor for higher speed and expanded operational zone;
Encrypted digital radio command guidance for better anti-jamming capability;
New onboard power unit with much reduced weight;
Increased G limit;
Ground station
Computerised fire-control system to improve the missile’s accuracy and reliability;
Extra high-frequency range-finding radar, electro-optical director and mono-pulse radar on the ground guidance station;
Multiple guidance (radar, electro-optical) for higher resistance against active and passive jamming;
Automated command and control (C2) system with a large display screen
Launcher
Self-propelled (tracked) launcher with self-adjustment capability and onboard power unit for increased mobility and reduced reaction time;
Simplified ground support equipments;
If necessary, the missile could also be launched from the older HQ-2 launcher
A HQ-2 SAM mounted on the fixed launcher in ready to fire mode (Source: Chinese Internet)
HQ-3
In the mid-1960s, the United States Air Force began to deploy the SR-71 Black Bird strategic reconnaissance aircraft, which could fly at a speed of Mach 3.0 and an altitude of 27,000~30,000m. Realising the HQ-2 in development was incapable of handling this new threat, the PLA quickly initiated two new SAM designs based on the HQ-1/S-75, a modestly modified variant designated HQ-3, and a radically modified variant designated HQ-4.
Like the HQ-2, the HQ-3 was also based on the Soviet S-75, which was being produced in the PRC as the HQ-1. Intended for engaging high-speed, high-altitude targets, the HQ-3 featured a total of 79 modifications in its missile, guidance station and ground equipment.
The development of the HQ-3 was initially carried out by Beijing-based 2nd Space Academy. However, the missile suffered from serious design flaws. Later Shanghai 2nd Bureau of Machinery and Electronics became involved in the development programme. In August 1969, it was decided that the whole development project was taken over by Shanghai 2nd Bureau.
During the design finalisation fire testing in July 1970, eight HQ-3 missiles were fired, with none hitting the target. The modified design was tested again in 1974, with two missile launched and one of them successfully hitting a high-speed, high-altitude target drone. The development was announced a success but the missile did not enter production.
HQ-4
The HQ-4 was the so-called “radically modified” variant derived from the HQ-1/S-75. Like the HQ-3, the HQ-4 was also intended for engaging high-speed, high-altitude targets. The HQ-4 featured a phased-array guidance radar for longer detection range. The development programme was later cancelled due to technical and financial difficulties.
TQ-2
The TQ-2 (Tuqiang-2) is the high-speed, high-altitude target drone developed from the HQ-2 SAM. The drone has been used to evaluate the effectiveness of the HQ-2, HQ-3 and HQ-4 SAM systems.
The TQ-2 high-altitude, high-speed target drone for missile testing (Source: Chinese Internet)
M-7
The SA-2/HQ-2 can play a secondary role as surface-to-surface missile. Egypt reportedly used its SA-2 SAM in this manner during the 1973 Arab-Israeli war. The project of converting the existing HQ-2 into surface-to-surface role was known as “Project 8610”. The missile was reportedly sold to Iran and North Korea under the export name M-7 in the 1980s.
