The ZSU-57-2 in service of the Yugoslav People's Army
The ZSU-57-2 (Ob'yekt 500) is a Soviet self-propelled anti-aircraft gun (SPAAG), armed with two 57 mm autocannons. 'ZSU' stands for Zenitnaya Samokhodnaya Ustanovka (Russian: Зенитная Самоходная Установка), meaning "anti-aircraft self-propelled mount", '57' stands for the bore of the armament in millimeters and '2' stands for the number of gun barrels. It was the first Soviet mass-produced tracked SPAAG. In the USSR it had the unofficial nickname "Sparka", meaning "pair", referring to the twin autocannon with which the vehicle is armed.
|Croatian ZSU-57-2 in Vukovar war museum|
During 1945 was made a smaller amount of the new self-propelled vehicle ZSU PA-37, which was based on a self-propelled vehicle SU-76m, such as the armored turret body mounted to open one gun K-61, 37 mm caliber. This weapon has retained all the bad characteristics of SU-76M, above all, not strong and unreliable engines. The total has made just over 70 ZSU-37. February 1946 design bureau 174 from Omsk Institute, its proposed solution based on the T-34, in which pivoting to four 37mm cannons. But in early 1947, a decision that future self-propelled weapon must stem from a body of the tank T-54 and PA guns caliber 57mm, which was practically started the development of future ZSU-57 / 2.
The first prototype of ZSU-57/2 has passed internal factory tests in June 1950, and something slightly different second prototype was completed in December of the same year for the state examination, which was conducted from 27 January to 15 March 1951 and included 1,500 traveled km and 2,000 shots. It was determined that the weapon meets the needs of protection of tank and mechanized units against attacks from the air and another is making trial lots for further testing. In May 1951 completed 6 perfected specimen for Army testing. Among other changes increased the fighting and set with 272 to 300 rounds 57mm.
|Detail from military exercises Bilogora 77 October 1977|
After a long negotiation on 4 August 1961 with the Soviet Union has concluded a contract on a large loan for the purchase of weapons. The total value of the contract was the US $ 115,912,474 (or about 900 million of today's dollars), and delivery under this contract lasted until 1965. Yugoslav delegation on 15 October 1962 demonstrated a self-propelled weapon ZSU-57, with an offer of 88,000 US dollars (about 690,000 today) for a weapon with two spare tubes. Obviously impressed, Yugoslav military leadership moved quickly and already on 23 November 1962 an agreement was signed that It concluded the purchase of 40 tools with 50,000 bullets.
|ZSU-57-2 Soviet self propelled anti-aircraft gun|
During 1963 was completed delivery of weapons, and the following year was purchased 16, 1965 was purchased another 69 ZSU-57. A total of 125 weapons was considerably improved capabilities of the Air Defense of the armored units.
During the 1991-95 war in the former Yugoslavia ZSU-57, the mainly used for attacks on infantry and fortified positions, as in the rest of the practice for all other anti-aircraft weapons.
Weight 28.1 tons
Length 8.46 m with gun in forwarding position (6.22 m hull only)
Width 3.27 m
Height 2.71 m
2.75 m (with a tarpaulin top)
Crew 6 (commander, driver, gunner, sight adjuster, and two loaders)
Armor 8–15 mm
2 x 57 mm L/76.6 S-60 anti-aircraft autocannons (57 mm S-68A variant) (300 rounds)
Engine V-54, 4-stroke, airless (mechanical)-injection, water-cooled 38.88 liter V12 diesel
520 hp (388 kW) at 2,000 rpm
Power/weight 18.5 hp/tonne (13.81 kW/tonne)
Suspension individual torsion bar with hydraulic shock absorbers on the first and last road wheels
Ground clearance 425 mm
Fuel capacity 830 l (including two externally mounted fuel tanks, 95 l each)
Range 420 km (road) 320 km (off-road)
Speed 50 km/h (31 mph) (road) 30 km/h (off-road)