T-64B in 1976. The later T-80B, in 1978, was also armed with this system. The Gyurza system continued to be developed, dropping the IR guidance system in favour of radio command guidance - it was then developed into the Shturm or AT-6 Spiral. Description The 9M112 Kobra missile consists of two sections: 9M43 head section – containing the 9M129 shaped charge warhead and the 9D129 sustainer motor 9B447 tail section – containing a battery, the flight controls, a light source for the guidance system on the tank to track and a small antenna to receive commands from the tank The two separate sections are stored in the autoloader of the tank in the same way as conventional 125 mm rounds. As the round is hoisted into the gun the two halves are mated together. The missile can be fired in any of three modes: Primary mode – the gun is elevated three degrees above the line of sight to reduce the amount of dust generated by the missile launch. This is critical since the tank has to see both the target and the light source on the rear of the missile in order to be able to guide the missile to the target. The missile system uses SACLOS guidance, the gunner has to keep the crosshairs centered on the target and the 1A33 fire control system generates course corrections, which are broadcast to the missile. Accuracy at 4000 m is estimated to be 80% in this mode. Ballistic mode – the gun is elevated three degrees above the line of sight. The missile then flies three to five meters above the gunner's line of sight, dropping down to the line of sight just before reaching the target. This further reduces the amount of dust kicked up by the flight of the missile, reducing the chance of the guidance system losing the missile. Emergency mode – this mode is only for use when a target suddenly appears within 1000 m and the missile is already loaded. The gun is at only 40 minutes of arc above the line of sight to the target, and the command link is activated early. The hit probability is lower in this mode. The missile has a muzzle velocity of 125 m/s, this increases to 800 m/s at its peak, but averages out at 350 to 400 meters a second. The flight time to 4000 meters