OVERVIEW: The ZSU-23-4 "Shilka" is a highly mobile and lightly armored self-propelled anti-aircraft gun (SPAAG) which mounts four liquid-cooled 23mm automatic cannons and a fully integrated stabilized radar fire control system. 

DETAILS: The ZSU-23-4 consists of a fully stabilized turret mounted on a GM-575 fully-tracked chassis. The turret mounts four 2A7 23mm liquid-cooled autocannons capable of a cyclic rate of fire of 800-1000 rounds per minute (RPM) each for a total volume of fire of 3200-4000 rounds per minute. The 2A7 guns are the liquid-cooled derivative of the 2A14 23mm air-cooled autocannons used on the ZU-23-2 towed anti-aircraft gun and both weapons use the same ammunition. The Shilka is typically loaded with 2000 rounds in 500-round belts per gun and can carry an additional 2000-4500 rounds of on-board ammunition depending on model. The 23mm guns have an effective AA range of 2500m. The gunner typically engages targets using short 3-5 round bursts per gun to reduce overheating and to conserve ammunition. 

An RPK-2 "Tobol" (NATO name: GUN DISH) radar is mounted on top of the turret and is used for searching, target acquisition, and fire control on a locked target. The fire control system is fully automated with the radar and uses an analog computer to determine superelevation and azimuth lead for the guns based on radar tracking information. Optical sighting can be used in degraded mode in the event of system failure or ECM.

The Shilka is usually deployed in the air defense batteries of Soviet motor rifle and tank regiments. The regimental air defense battery consists of a platoon of four ZSU-23-4 and a SA-9 Gaskin SAM platoon. For offensive operations the ZSU's typically operate approximately 400m behind the lead elements of the motor rifle and tank regiments, while the SA-9's deploy further back around the regimental command post to provide cover for higher value targets. It has also has a secondary role of providing direct fire support against ground targets. 

Specifications:

Maximum Acquisition Range: 	20km/12nm
Maximum Tracking Range:		18km/11nm
Engagement Envelope, range:	2500m/1.35nm (effective); 3000m/1.6nm (maximum range)  
Engagement Envelope, altitude:	1500m/5000ft (effective); 5000m/16,000ft (maximum slant range)
Kill probability:		0.07-0.12 (v. aerial targets)
Mobility:			Tracked, fording capability of 1m depth 


NOTES: IOC: 1965. The ZSU-23-4 was widely exported by the Soviet Union and has been used operationally in the Middle East, Southeast Asia, Southwest Asia, and Africa. 


SOURCES: "ZSU-23-4 Shilka." Weaponsystems.net. Accessed November 25, 2019. http://www.weaponsystems.net/weaponsystem/EE03%2520-%2520ZSU-23-4.html ; "ZSU-23-4 Shilka." Deagel.com. Accessed November 25, 2019. http://www.deagel.com/Artillery-Systems/ZSU-23-4-Shilka_a001864001.aspx ; FM 100-2-3. Washington D.C.: Headquarters, Department of the Army, 1991 ; "NEW CAPABILITIES FOR THE ZSU-23-4 SHILKA." Defence-ua.com,  published 22 December 2017. Accessed 25 November 2019. Defense Express Media & Consulting Company, Kiev, Ukraine.