HQ-2 (CH-SA-1)

The HQ-2 is a Chinese-produced high-altitude, medium-range surface-to-air missile system, reverse-engineered and improved from the Soviet S-75 Dvina. It is designed to engage high-altitude aircraft and has undergone numerous upgrades throughout its service life.

Developed in the 1960s following the Sino-Soviet split, the HQ-2 program was initiated to secure China's airspace against high-altitude reconnaissance flights after Soviet technical assistance was withdrawn. Entering service in 1967, the system achieved notable combat success by shooting down several Taiwanese-piloted U-2 spy planes and American unmanned reconnaissance drones during the Cold War. It was also widely exported to nations such as Iran, where it saw action during the Iran-Iraq War, and served as the foundation for China's subsequent domestic air defense developments. Although largely replaced in active People's Liberation Army service by modern systems like the HQ-9, the HQ-2 remains in reserve and continues to be operated by several foreign militaries.