Known by the NATO reporting name SA-3 GOA, this Soviet medium-altitude surface-to-air missile (SAM) is actually named the Isayev S-125. medium altitude surface-to-air missile system uses a two-stage, solid-fuel missile built by the Isayev OKB. While it is obsolete today, many have been exported and still can be a threat. It also has command-guided capability to attack land and sea targets.
It is a two-stage rocket, with a 2.6 second burn time booster and a 18.7 second sustainer. Guidance signals are sent to an antenna on the rear of the fixed fins of the second stage; the second stage also has movable steering fins.
While the system was originally intended for fixed sites, it has a set of trucks that can move the entire system. The overall process of reloading takes approximately an hour; the launchers have 2 or 4 missile rails.
In the original deployments, long-range warning and target acquisition came from the FLAT FACE radar, which has been replaced, in many units, with the SQUAT EYE radar. SQUAT EYE has improved low-altitude coverage due to a mast-mounted radar.
This system has a practical range of approximately 25 km.
- Federation of American Scientists, S-125 SA-3 GOA