Air Defense

MT-LB with Zastava M55 anti-aircraft gun

Also known as
  • MT-LB Zastava M55
  • MT-LB M55
  • MT-LB with M55A3B1
  • MT-LB with M55A4B1
  • MT-LB with M55 AA gun
  • MT-LB with 20/3 mm M55

The MT-LB with Zastava M55 anti-aircraft gun was an Armenian/Artsakh field conversion that mounted Yugoslav/Serbian 20 mm triple M55A3 or M55A4 guns on the rear deck of the Soviet MT-LB tracked carrier. In the 2020 Nagorno-Karabakh war, open-source loss records and regional reporting documented these vehicles as short-range air-defense and direct-fire support systems that were destroyed, damaged, or captured by Azerbaijani forces.

MT-LB with Zastava M55 anti-aircraft gun, Tracked self-propelled anti-aircraft gun conversion, Air Defense
Image source: HS.831, Zastava M55, and DShK

Role in Conflicts

2020 Nagorno-Karabakh Conflict
Air DefenseFire SupportCaptured, Seized & Recovered

Armenian/Artsakh forces fielded MT-LB carriers fitted with Zastava M55 20 mm triple anti-aircraft guns during the 44-day war; Oryx lists 35 visually documented destroyed, damaged, or captured examples. Later reporting identified captured M55A3B1 and M55A4B1 gun fits, while September 2023 seizure reporting listed three MT-LB ZG-20/3 "Zastava" vehicles among confiscated Karabakh equipment.

Documented Conversion Context

The public record ties this entry to Armenian and Artsakh MT-LB field conversions rather than factory-built MT-LB air-defense vehicles. Regional reporting identified captured examples with M55A3B1 and M55A4B1 guns, and official Azerbaijani material later described seized 20 mm Zastava guns on MT-LB tracked vehicles being repaired for air-defense training.

Visual record

Oryx lists 35 Armenian MT-LB with Zastava M55 AA gun losses or captures from the 2020 war.

Source: The Fight For Nagorno-Karabakh: Documenting Losses On The Sides Of Armenia And Azerbaijan.

Postwar handling

Azerbaijan's defense ministry said seized 20 mm Zastava guns on MT-LB vehicles were repaired and transferred into armament for air-defense exercises.

Source: Air Defense Units Of The Combined Arms Army Conducted Tactical-Special Exercises.

Profile / Specs

Profile

Origin
Soviet Union / Yugoslavia; Armenian field conversion
Type
Tracked self-propelled anti-aircraft gun conversion
Service note
2020 Nagorno-Karabakh War improvised air-defense and fire-support configuration
Designer
MT-LB by Soviet designers; M55 gun by Crvena Zastava/Zastava Arms
Designed
MT-LB from the 1960s; M55 family from the 1950s-1970s
Produced
MT-LB production from the 1960s onward; Zastava M55 family produced from the Cold War era onward

Specifications

Armament
Zastava M55 20 mm triple-barreled automatic anti-aircraft gun mounted on an MT-LB tracked chassis
Gun caliber
20 x 110 mm Hispano cartridge
Effective range
About 2,000 m against air targets and 2,500 m against ground targets for the M55 gun
Feed system
Three 60-round top-fed drum magazines on the M55 gun
Base chassis
MT-LB fully amphibious tracked armored carrier with welded steel armor and a 240 hp YaMZ-238 diesel engine
Mobility
Baseline MT-LB road speed about 62 km/h with about 500 km road range before conversion-specific weight and balance changes
Protection
Light steel armor against small arms and shell splinters; exposed gun crew and mount on the rear-deck conversion
Variants

The page tracks the MT-LB field conversion rather than the towed M55 gun family as a whole; the public evidence distinguishes M55A3B1 and M55A4B1 gun fits on captured Armenian vehicles.

VariantConfigurationDesignation notes
MT-LB with M55A3B1M55A3B1 gun carrier

Balkan Security Network reported Armenian MT-LBs armed with M55A3B1 and M55A4B1 guns; Russia Beyond describes M55A3B1 as the version with a new sight and semi-automatic laying device.

Sources: Zastavin trocevac iz ratnog plena u vojsci Azerbejdžana, Russia Beyond M-55 On MT-LB In The Caucasus

MT-LB with M55A4B1M55A4B1 gun carrier

Balkan Security Network reported Armenian MT-LBs armed with M55A4B1 and M55A3B1 guns; Russia Beyond describes M55A4B1 as the version with the Galileo sight-computer-hydraulic device.

Sources: Zastavin trocevac iz ratnog plena u vojsci Azerbejdžana, Russia Beyond M-55 On MT-LB In The Caucasus

Base Chassis And Related MT-LB Gun Conversions

This record is one of several cataloged MT-LB-based weapon carriers documented in the 2020 Nagorno-Karabakh war.

Compatible itemItem typeCompatibility evidence
MT-LB, Amphibious tracked armored personnel carrier and artillery tractor, Armored VehiclesMT-LBTracked armored carrier chassis

The conversion used the Soviet MT-LB tracked carrier as its base vehicle, with a Zastava M55 20 mm triple anti-aircraft gun installed on the rear deck.

Sources: Azerbaijan Reveals MT-LB Armored Vehicles As Armenian War Spoils, MT-LB Armoured Personnel Carrier

MT-LB with ZU-23 anti-aircraft gun, Improvised tracked self-propelled anti-aircraft gun, Air DefenseMT-LB with ZU-23 anti-aircraft gunTracked anti-aircraft gun conversion

The linked record covers a related Armenian/Artsakh MT-LB air-defense conversion using the Soviet ZU-23 gun; Oryx lists both MT-LB with Zastava M55 and MT-LB with ZU-23 losses in the same 2020 Nagorno-Karabakh loss documentation.

Sources: The Fight For Nagorno-Karabakh: Documenting Losses On The Sides Of Armenia And Azerbaijan

Timeline

MT-LB with Zastava M55 anti-aircraft gun Key Events

  1. Armenian conversions documented in combat

    Open-source loss records documented MT-LB chassis fitted with Zastava M55 anti-aircraft guns among Armenian/Artsakh equipment destroyed, damaged, or captured during the 2020 war.

    Sources: The Fight For Nagorno-Karabakh: Documenting Losses On The Sides Of Armenia And Azerbaijan

  2. Captured vehicles reported after the war

    Balkan Security Network reported that Azerbaijan held captured Armenian MT-LB vehicles with M55A3B1 and M55A4B1 guns after the 44-day war.

    Sources: Zastavin trocevac iz ratnog plena u vojsci Azerbejdžana

  3. War-spoils display reported

    Defense Brief reported Azerbaijani images of captured Armenian MT-LB vehicles fitted with Zastava M55A4 20 mm guns.

    Sources: Azerbaijan Reveals MT-LB Armored Vehicles As Armenian War Spoils

  4. Three Zastava conversions listed after September offensive

    RBC-Ukraine, citing Azerbaijan's defense authorities, listed three MT-LB ZG-20/3 "Zastava" vehicles among equipment confiscated after Azerbaijan's September 2023 Karabakh operation.

    Sources: Tanks, Guns And Air Defense Systems: Azerbaijan Shows Military Equipment Confiscated In Karabakh

Media

MT-LB with Zastava M55 anti-aircraft gun Images

MT-LB with Zastava M55 anti-aircraft gun, Tracked self-propelled anti-aircraft gun conversion, Air Defense - view 1
Source: Soviet MT-LB.JPEG
MT-LB with Zastava M55 anti-aircraft gun, Tracked self-propelled anti-aircraft gun conversion, Air Defense - view 2
Source: MT-LB Multi-Purpose Tracked Vehicle
Related Weapon Systems
MT-LB with ZU-23 anti-aircraft gun, Improvised tracked self-propelled anti-aircraft gun, Air DefenseAir DefenseMT-LB with ZU-23 anti-aircraft gunImprovised tracked self-propelled anti-aircraft gunThe MT-LB with ZU-23 anti-aircraft gun is an improvised tracked fire-support and short-range air-defense vehicle that combines the Soviet MT-LB multipurpose armored tractor with a twin 23 mm ZU-23 gun mount. Public records show the configuration in Iraqi, Russian, Ukrainian, Syrian, and Armenian or Artsakh service contexts, with documented examples ranging from an Iraqi wreck in Baghdad to vehicles destroyed, damaged, or captured in later wars.
60 mm M57 mortar, 60 mm light infantry mortar, ArtilleryArtillery60 mm M57 mortar60 mm light infantry mortarThe 60 mm M57 is a Yugoslav-pattern smoothbore light infantry mortar now listed by Serbian manufacturer PPT Namenska and in Yugoimport export material. Its official sheets describe a high-angle fire-support weapon built around barrel, base plate, bipod, sight, tools, spares, and accessories; post-Yugoslav records also show Serbian surplus stocks and Balkan export activity. In the 2020 Nagorno-Karabakh Conflict, open-source loss documentation recorded M57 mortars captured from Armenian forces.
MT-LB with 25 mm 2M-3 naval gun, Improvised tracked self-propelled anti-aircraft gun, Air DefenseAir DefenseMT-LB with 25 mm 2M-3 naval gunImprovised tracked self-propelled anti-aircraft gunThe MT-LB with 25 mm 2M-3 naval gun is a Russian improvised weapons carrier that combines the Soviet MT-LB tracked armored tractor with a twin 25 mm 2M-3 or 2M-3M naval anti-aircraft mount. Open-source reporting and Russian loss documentation tie the conversion to the full-scale 2014 Russia-Ukraine War, where it appears as a short-range air-defense and direct-fire adaptation rather than a standardized factory combat vehicle.

Sources

The Fight For Nagorno-Karabakh: Documenting Losses On The Sides Of Armenia And AzerbaijanPublisher: Oryx | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by visually documenting MT-LB with Zastava M55 AA gun vehicles used by Armenian/Artsakh forces and listing destroyed, damaged, and captured examples. | Accessed: 2026-06-20Zastavin trocevac iz ratnog plena u vojsci AzerbejdžanaPublisher: Balkan Security Network | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by reporting MT-LB vehicles with M55A3B1 and M55A4B1 guns used by Armenian forces in the 44-day war and later captured by Azerbaijan. | Accessed: 2026-06-20Azerbaijan Reveals MT-LB Armored Vehicles As Armenian War SpoilsPublisher: Defense Brief | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by reporting MT-LB vehicles fielded by Armenian forces with Zastava M55A4 20 mm guns and shown by Azerbaijan as captured war spoils. | Accessed: 2026-06-20Captured Three-Barrel Cannon On MT-LB Spotted In The Azerbaijani ArmyPublisher: VPK.name | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by reporting M55 Zastava guns on MT-LB vehicles captured from Armenian troops in Nagorno-Karabakh and later seen in Azerbaijani service context. | Accessed: 2026-07-02Air Defense Units Of The Combined Arms Army Conducted Tactical-Special ExercisesPublisher: Ministry of Defense of the Republic of Azerbaijan | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by stating that 20 mm Zastava anti-aircraft guns on MT-LB tracked vehicles were seized as trophies during the 44-day war, repaired, and transferred into Azerbaijani armament. | Accessed: 2026-07-02Tanks, Guns And Air Defense Systems: Azerbaijan Shows Military Equipment Confiscated In KarabakhPublisher: RBC-Ukraine | Note: Supports 2020 Nagorno-Karabakh Conflict catalog context by reporting three MT-LB ZG-20/3 "Zastava" vehicles among equipment confiscated after Azerbaijan's September 2023 Karabakh operation. | Accessed: 2026-07-02Russia Beyond M-55 On MT-LB In The CaucasusPublisher: Russia Beyond Serbia | Note: Supports 2020 Nagorno-Karabakh Conflict direct use by reporting Nagorno-Karabakh forces using M55-on-MT-LB conversions for troop air defense during the 2020 fighting, and distinguishes M55A3B1 and M55A4B1 sighting and laying equipment. | Accessed: 2026-07-02M-55A 20MM Anti-Aircraft GunPublisher: The Royal Canadian Artillery Museum | Note: Supports Zastava M55 background, producer, gun type, detachment, and range context. | Accessed: 2026-06-20MT-LB Armoured Personnel CarrierPublisher: Army Recognition | Note: Supports MT-LB chassis background, protection, engine, speed, range, amphibious capability, and baseline layout specifications. | Accessed: 2026-06-20MT-LBPublisher: Army Guide | Note: Supports MT-LB manufacturer, armored carrier role, amphibious design, cargo/towing capacity, crew, and chassis specifications. | Accessed: 2026-06-20HS.831, Zastava M55, and DShKPublisher: Wikimedia Commons | Note: Supports image provenance and CC BY-SA 4.0 license for the Zastava M55 image used as the primary component image. | Accessed: 2026-06-20Soviet MT-LB.JPEGPublisher: Wikimedia Commons | Note: Supports image provenance and public-domain status for an MT-LB chassis reference image. | Accessed: 2026-06-20MT-LB Multi-Purpose Tracked VehiclePublisher: Wikimedia Commons | Note: Supports image provenance and public-domain status for a second MT-LB chassis reference image. | Accessed: 2026-06-20