individual torsion bar suspension, a rear drive sprocket with detachable sprocket rings (lantern-wheel gear) and an idler wheel on each side. The first and last road wheels each have a hydraulic rotary shock absorber. The track is 12.33 m long, 580 mm wide and has 90 links; despite having four road wheels instead of five the ground contact area of the track is the same as the T-54 (3.84 m). Track center distance is 2.64 m The vehicle has a ground pressure of 0.63 kg/cm2. Other equipment The ZSU-57-2's electrical power unit partially differs from the T-54, in that it consists of a more powerful G-74 direct current generator which develops 3 kW (108 A at 27–29 V) at 2100 rpm and six 24 volt 6-STEN-140M or 6-MST-140 accumulator batteries (total battery capacity is 420 A-h), the batteries are used for starting the engine and an electrical power supply when the generator is shut down. The ZSU-57-2 is equipped with an automatic anti-aircraft sight of the plotter type with two collimators which can supervise a target with a speed of up to 350 m/s, a dive angle of between 0° and 90° and a slant range of up to 5,500 m; a simple mechanical sight is provided in case of failure. There is also an optical sight for direct fire at ground targets. The 10RT-26E portable radio transceiver is located on the right hand side of the turret interior. It has a range of 9 to 20 km when the vehicle is stationary, and from 7 to 15 km when the vehicle is on the move. It was later replaced by R-113 or R-113 radio transceivers. The TPU-4-47 intercom system was later replaced by R-120 or R-124 intercom systems. Small arms for the crew members include two AK-47 assault rifles and a 26 mm signalling pistol. Weaknesses The main weakness of the ZSU-57-2 was the lack of a search or fire-control radar; the vehicle was equipped with an optical mechanical computing (analog) reflex sight as the sole fire control system, so it could engage visible targets only. Night firing was also impractical. Also, the manual gunlaying and manual clip loading was not good enough, the rate of fire is not high enough, particularly considering that air-cooled barrels require quite long pauses for cooling at high rates of fire and the turret traverse is not fast enough to effectively intercept high-speed