The S-60 was designed primarily as a 57mm single-barreled, towed, anti-aircraft defense system. The gun was developed in the late 1940's and was influenced by captured German systems of World War 2 - specifically, the 5.5-cm Gerat 58 and the 5cm Flak 41 series guns. The S-60 itself became a short-to-medium range weapon featuring robust qualities and able to engage lowing flying aircraft and even lightly armored vehicles. The weapon system was introduced to Warsaw Pact nations in 1950 and soon after, the gun was sold to communist-friendly nations throughout the Middle East and South Asia.
The original S-60 had a long thin barrel capped by a multi-perforated muzzle brake. A large gun shield was affixed to both sides of the barrel and served as a reminder of her German origins. Regardless, the shield did little in protecting the seven-man crew charged with maintaining, arming and manning the weapon system. The shield folded away during transport as did the horizontal ammunition feed tray. Four road wheels supported the carriage during road travel. A travel brace was fitted between the forward pair of tires and served to lock the main barrel in place during journeys.
The S-60 fired a 57mmx384R caliber six pound projectile and, in 1950, two basic types were made available - the armor piercing (API-T) round and the high explosive (HEI-T) round. The crew would load the 30-pound, 4-round clips into the horizontal feed tray. To increase loading speed, the designers attached an ammunition "ready rack" to the left side of the S-60 breech that could hold 4 x 4 round clips, ready to fire, near the feed mechanism. The gun proved stable when fired and made use of a three-point jack system which would lift the gun system off of the ground from her four wheeled carriage. The normal Soviet prime mover for the time, and the vehicle charged with towing the S-60, was the Ural-375 general purpose truck - an all-around 4.5 ton 6x6 vehicle produced at the Russian Ural Automotive Plant. The truck had two gas tanks holding 95 gallons each and her range was 450 miles at a 25 mile per hour pace.
The S-60 is Improved
Demand for sales in the Warsaw Pact countries led to improvements in the S-60's fire control system. Initially, the gun operated only with an on-carriage optical system for target rangefinding. As the enemy improved her fighting aircraft technology, the initial manually-operated firing system became limited. As a solution, the Soviets adapted a flap wheel PUAZO-5 director and SON-4 radar system for improved capabilities. The calculator and the radars were transported into action by the same Ural 375 series trucks. As the radar was introduced, the range of the S-60 was increased from 4,000 meters (using the original optical ranging equipment) to 6,000 meters with the SON-4 radar system. The radar improved the defensive role of the S-60 against planes, helicopters and even some light armored vehicles. Soon, this system was upgraded with the PUAZO-6/60 director and the SON-9 or SON-9A radars. A self-propelled gun (SPG) model was then produced with both twin- and quad-barrel fittings. These versions were mated to the T-54 main battle tank chassis and designated as S-68 (or ZSU-57-2) in 1957.
The S-60, the self-propelled ZSU-57-2 and the Type-59 (itself a Chinese-produced version of the Soviet S-60), was exported to Vietnam in great numbers during the Vietnam War. These were used as ground support weapons to protect high profile targets such airfields, bridges and military bases. Hundreds of S-60's became the backbone of the low-altitude air defense system across the North and covered some 460 meters (1,500ft) and 1,500 meters (5,000 ft) of air space. The S-60 was developed into a navalized form for use on Soviet surface vessels as the AK-725. The ZIF-72 existed as a similar naval vessel but housed within a metal structure. China also made use of the ZSU-57-2 as the Type 80. Poland made a license-production version all their own under the Tarnow Metal Works banner.
The Soviet anti-aircraft organization deployed its S-60 groups numbering 24 guns. A regimental AA battery network consisted of six guns, and a fire control radar director. New German-designed fire control system (the SON-9) was installed in the S-60. The new system brought with it an improved distance measuring calculator along with a modern radar called the "RPK-1 Vaza". However, some older S-60 models still maintained their original flap wheel as the radar fire control system.
The World Over
The S-60 and its variants were used in wars all over the globe to aid Communist military goals. The S-60 was used against the Israeli Air Force (IAF) in the Six-Day War as well as in Yom Kippur. The S-60 protected Soviet air fields during the Afghanistan War and was used extensively during the Vietnam Conflict. Both sides of the Iran-Iraq War used the S-60 and Iraq, once again, put these systems to good use in the 1991 Gulf War. Some fifty years of total active service has since proved the German-Soviet design's worth.
Technologically superior Soviet/Russian Surface-to-Air Missile (SAM) systems have replaced the outdated towed S-60 gun and its variants within the Russian inventory.