Ukrainians learn to defend against guided bombs: how Soviet-era ZU-23-2 guns help counter Russian threat

Contents:

1. What is the ZU-23-2
2. Technical characteristics of the ZU-23-2
3. Ukrainian ZU-23-2
4. ZU-23-2 during the full-scale war
5. What are KABs and how Russia used them
6. How to fight guided aerial bombs

What is the ZU-23-2

The ZU-23-2 is a Soviet twin 23mm anti-aircraft gun. It was developed in the late 1950s for targeting airborne threats up to 2.5 km in altitude and lightly armored targets up to two kilometers away from military formations. Mass production began in 1955, and it was adopted into the Soviet Union’s armament in 1960.

More than 14,000 of these anti-aircraft systems were produced in the Soviet Union, with license production in China, Bulgaria, Poland, and Egypt.

Before the advent of man-portable air-defense systems (MANPADS), the 23mm anti-aircraft gun was intended to combat low-flying aircraft. It was later widely used to target infantry, soldiers, and weapons. Although most often used against infantry, aircraft, and lightly armored vehicles, there are also known cases of successful use against tanks. For example, during the Nigerian Civil War (2015-2018), insurgents used ZU-23 guns mounted on pickup trucks to destroy government army tanks.

Photo: armyinform

They were also extensively used during the Afghanistan War (1979-1989), the Russian-Chechen wars in the 1990s, civil wars in Syria and Libya, and in the Russo-Ukrainian War.

Technical characteristics of the ZU-23-2

• Length – 4.57 m
• Barrel length – 2 m
• Width – 2.88 m
• Height – 1.22 m
• Crew – 6 people
• Caliber – 23 mm
• Effective range of fire – 2.5 km (altitude), 2 km (distance)
• Initial projectile speed – 950 m/s
• Maximum target speed – 300 m/s (400 m/s for Z-23M)
• Rate of fire – 2000 rounds/min
• Time to transition from combat to march position – 30 sec

Photo: dpsu.gov.ua

Ukrainian ZU-23-2

The Artillery Weapons design bureau, part of Ukroboronprom, developed and began manufacturing the 23mm KBA40 barrel for the ZU-23-2 anti-aircraft system. In 2019, Ukrainian-made barrels were authorized for use by the Ministry of Defense.

Later, the company Ukrainian Armored Vehicles developed a localized version of the ZU-23-2 (2A13). It is known that tests of this equipment took place, including in 2020 at the Rivne training ground.

At the beginning of 2021, the Mayak factory announced that it had mastered the serial production of spare parts, tools, and devices for the ZU-23-2. Additionally, the Ukrainian Armed Forces continued to procure parts for them through ProZorro.

Photo: dpsu.gov.ua

ZU-23-2 during the full-scale war

After Russia’s full-scale invasion, the Defense Forces received systems transferred by allies, including from Poland. Ukrainians also combined ZU-23s with other weapons supplied. An American publication, Forbes, dedicated an article to a “new air defense machine” Ukraine received by mounting ZU-23-2 guns on an American M113 armored personnel carrier. The 14-ton aluminum vehicle with a 275-horsepower diesel engine also provides space for two crew members and 11 passengers.

“What the M113 lacks in armored protection, it compensates with space, mobility, and versatility. Add armor and a turret, and you can turn the M113 into a combat vehicle. Add a ZU-23-2 – and you get a highly mobile air defense and infantry support vehicle. The only surprising thing is that it took so long to combine them, considering the allies provided the Ukrainian army with nearly a thousand M113s,” Forbes emphasized.

Since 2022, ZU-23-2 anti-aircraft guns mounted on chassis or trailers have been standard weapons for strike anti-drone groups. Ukrainian forces, in particular, mounted anti-aircraft systems on GAZ-66 vehicles.

“Ukrainian combat mobile groups use deadly anti-aircraft guns in two ways: direct aiming, when the enemy is visible, or from hidden positions. In the second case, targets are identified using drones, and the shells are detonated remotely after firing, covering the enemy with a hail of shrapnel,” stated a television report posted on the Joint Forces grouping page.

Mostly, Ukrainian defenders hunted for the Lancet drones, and occasionally for Zala or Supercam drones. ZU-23 was also used to provide cover for multiple rocket launch systems (MRLS) like Grad.

However, the most notable hit was recorded during the counteroffensive in Kharkiv region. There, the soldiers of the 80th Brigade managed to shoot down an enemy Su-30 aircraft using a ZU-23.

What are KABs and how Russia used them

A guided aerial bomb (KAB) is an aerial bomb equipped with aerodynamic surfaces and a guidance system to improve accuracy. After the creation of KABs, older aerial bombs were referred to as "unguided" or "dumb" bombs.

Aerial bombs are dropped from an aircraft and separate from the holder with a small speed by forced detachment or under the influence of gravity. The range depends on the carrier's parameters (speed and altitude). The higher and faster the aircraft drops the KAB, the farther the bomb will fly.

Guided aerial bombs became a major threat to Ukraine because Russia has a large stockpile of them. For example, on November 5, 2023, the enemy launched 87 guided aerial bombs over the de-occupied territory of Kherson. On November 7, the occupiers used more than 100 KABs.

KABs are also dangerous because they are not very accurate. The Russians do not target specific objects but rather fire at a sector where the bombs cause massive destruction. A few KABs can completely destroy a five-story building.

The most devastating strike by Russia occurred on March 16, 2022. The strike on the Mariupol Drama Theater killed at least 300 people, many of them children.

How to fight guided aerial bombs

KABs can be shot down using air defense systems. However, since bombs are launched along the entire front line, it is not feasible to develop such a wide air defense network and equip it with missiles. It is also illogical to shoot down cheap bombs with aircraft.

The best solution, experts say, would be to target the carriers. However, enemy aircraft approach the frontline at a distance of 40-50 km and launch bombs. The Russians are well aware of the capabilities of Ukraine’s air defense – Ukrainian surface-to-air missile systems, such as the S-300, can shoot down targets at a range of up to 75 km, and Buk-M1 – up to 35 km. Placing Patriots near the line of contact would expose them to unnecessary risk. Similarly, F-16 fighters are kept away from close combat. Strikes on airfields may delay the enemy’s operations, but they cannot prevent them.

“Developments to counter long-range Russian bombs were reported by Volodymyr Zelenskyy in April 2024. By July 2024, volunteer Serhiy Prytula announced the development of Ukrainian weapons against Russian KABs. At least by then, the weapon was being tested, and if its effectiveness was proven, mass production was to begin within a short period,” Defense Express wrote.

On January 6, a Russian guided aerial bomb was shot down in the Zaporizhzhia region, which was officially confirmed. According to the Air Forces, this was not the first case.

According to the Ukrainian aviation Telegram channel Sonashnyk, Ukrainian anti-aircraft gunners have been shooting down Russian long-range bombs using the ZU-23-2.

“We never had issues detecting KABs. The problem was with response time and the cost of use because the effective firing range of the guns is short, and missiles are expensive,” Sonashnyk explained.

For this reason, the Defense Forces explored the possibility of shooting down guided aerial bombs with Soviet "Zushkas." This possibility was also suggested by Army General Mykola Malomuzh. According to the general, this requires experience and precision from Ukrainian fighters. It is about the ability to accurately determine the trajectory of the target.

Defense Express also emphasizes that in this case, it is "not about the unique capabilities of this weapon, but about the unique skill of Ukrainian fighters and a dose of military luck." Sonashny notes that this involves a specific tactic and a Ukrainian solution that will gradually be scaled up.