ZSU-23-4 "Shilka"

The ZSU-23-4 "Shilka" is a Soviet-designed self-propelled anti-aircraft gun (SPAAG). Development occurred between 1957 and 1960 to address limitations of the ZSU-57-2, which lacked radar and the capability to fire while in motion. Manufactured by the Ulyanovsk Mechanical Plant and Mytishchi Machine-Building Plant, the vehicle entered service in 1965. Its primary purpose was the air defense of military facilities, troop formations, and mechanized columns.

The vehicle utilizes the GM-575 tracked chassis, incorporating components from the PT-76 light tank. Protection is provided by welded steel armor on the hull and turret. Armament consists of four 2A7 23 mm liquid-cooled autocannons, collectively designated AZP-23 "Amur." These weapons provide a combined rate of fire of 3,400 to 4,000 rounds per minute and are supplied by 2,000 rounds of ammunition stowed in belts. The 360-degree rotating turret is fully stabilized, allowing the system to engage targets while the vehicle is in motion.

Fire control is managed by the RPK-2 "Tobol" radar system, which operates in the Ku band to detect and track aerial targets. An 1A7 SRP electro-mechanical computer calculates flight time and lead angles based on radar data. The vehicle is operated by a crew of four: commander, driver, gunner, and radar operator. For ground engagements, the cannons elevate from -4 to +85 degrees, a feature utilized in mountainous and urban combat. Power is supplied by a 6-cylinder diesel engine and a gas turbine auxiliary power unit.

The ZSU-23-4 was produced in large numbers and exported to Warsaw Pact members and other states. It has seen service in conflicts including the Yom Kippur War, the Iran-Iraq War, and the Soviet-Afghan War. During the Afghan conflict, the system was used for mountain combat to return fire against ambushes from high-elevation positions. It was also deployed in the Gulf War, the Chechen Wars, and the Russo-Ukrainian War. The system remains in service in several countries, and various operators have developed modernization packages including surface-to-air missiles and digital fire control systems.