Threat of the Week
The 2K12 'Kub' (NATO reporting name: SA-6 'Gainful') mobile surface-to-air missile system is a Soviet low to medium-level air defense system designed to protect ground forces from air attack. '2К12' is the GRAU designation of the system.
Each 2K12 battery consists of a number of similar tracked vehicles, one of which carries the 1S91 (SURN vehicle, NATO designation 'Straight Flush') 25 kW G/H band radar (with a range of 75 km (47 mi)) equipped with a continuous wave illuminator,
in addition to an optical sight. The battery usually also includes four triple-missile transporter erector launchers (TELs), and four trucks, each carrying three spare missiles and a crane. The TEL is based on a GM-578 chassis, while the 1S91 radar
vehicle is based on a GM-568 chassis, all developed and produced by MMZ. The 2K12 system shares many components with the 2K11 Krug (SA-4) system. In many ways they are designed to complement each other; 2K11 is effective at long ranges and high altitudes,
2K12 at medium ranges and intermediate altitudes.
The system is able to acquire and begin tracking targets using the 1S91 Самоходная установка разведки и наведения' (SPRGU - 'Self-propelled Reconnaissance and Guidance Unit' / NATO: 'Straight Flush' radar)
at 75 km (47 mi) and begin illumination and guidance at 28 km (17 mi). IFF is also performed using this radar. It can only guide one or two missiles to a single target at any time. The missile is initially command guided with terminal semi-active radar homing (SARH),
with target illumination provided by the 'Straight Flush' radar. Detonation is via either the impact or proximity fuze. On the latest models, this vehicle is also fitted with an optical tracking system which allows engagement without the use of the radar
(for active RF emissions stealth reasons, or due to heavy ECM jamming) in which case the effective altitude is limited to 14 km/46000 ft. The optical tracking method also allows engagements to altitudes below that where the radar is able to track targets.
The maximum target speed is around Mach 2 for head-on engagements and Mach 1 for tail-chase engagements. The top speed of the missile is approximately Mach 2.8. In contrast to the elaborate Patriot missile or even the simpler Hawk system fielded by US forces,
most of the system rides on two tracked self-propelled vehicles, rather than towed or mounted on trucks, and either the launcher or control vehicle can be set to launch in only 15 minutes after changing location.
