M-84 - Tank Encyclopedia (2024)

Socialist Federal Republic of Yugoslavia
Main Battle Tank – ~650 Built

Introduction

The development and production of the M-84 main battle tank (MBT) by the Socialist Federal Republic of Yugoslavia perfectly embodied their national slogan, “Brotherhood and Unity,” bringing together the economies and production capacities of all six Yugoslav republics to create a source of national pride. Regarded as one of the best copies of the T-72 main battle tank, the M-84 was a unique product of the Yugoslavian geopolitical situation, combining an Eastern license with Western technology, the tenacity of its own military industry, and the long-standing aspirations of the Yugoslav People’s Army. Ironically, a decade after its construction, the country would collapse, and the tank built to protect Yugoslavia would instead be used as yet another tool in its destruction.

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Birth of a Tank Army

Emerging from the aftermath of World War II, the Yugoslavian National Army inherited a diverse array of Allied-supplied and captured armored vehicles. The primary tank forces, concentrated in the 1st and 2nd tank brigades, were equipped with M3A3 Stuarts provided by the British and T-34/85s supplied by the Soviets throughout the war. Recognizing the contribution of these brigades during the country’s liberation, a decision influenced by Soviet military doctrine, led to their expansion into tank divisions with supporting elements. These divisions were then organized into the First Tank Army, together with four independent tank brigades comprising captured Axis vehicles and 65 newly bought T-34/85s. However, challenges such as inadequate training and a lack of spare parts and ammunition for captured equipment rendered these units unfit for combat, prompting the abandonment of the Tank Army concept.

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The arrival of 308 more T-34/85s initially alleviated the issue of captured tanks, but the deterioration in relations after the Tito-Stalin split in 1948 severed ties with the Soviet Union, making it impossible to acquire new tanks and spare parts. Consequently, efforts were made to establish overhaul facilities and domestic production lines for T-34/85 spare parts, which was accomplished with moderate success. Enthralled by the notion of military self-sufficiency, the Yugoslav People’s Army (JNA) pushed for the full-scale production of a copy of the T-34/85, named “Vozilo A.” However, after the limited run of the five tanks, it became evident that the attempt had failed. Subsequently, the decision was made to acquire new tanks from Yugoslavia’s newfound partners in the West.

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In the late 1950s, facing the potential threat of a Soviet invasion, the Yugoslav Government openly sought material assistance from the United States, Britain, and France to equip its armed forces. In response, Western countries included Yugoslavia in the Mutual Defense Assistance Program (MDAP), leading to the delivery of American World War II-era surplus equipment. Alongside large amounts of M4E3A4 Sherman tanks, M18 Hellcat tank destroyers, and M36 Jackson tank destroyers, 319 M47 Patton tanks were also provided. However, the availability of spare parts for these aging machines dwindled quickly, rendering about one-fifth of the tank fleet inoperable by the end of the 1950s.

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Sitting on Two Chairs

The thaw in relations between the Soviet Union and Yugoslavia began in the mid-1950s, following Stalin’s death. With the diminished threat of a Soviet invasion, Yugoslavia withdrew from the Mutual Defense Assistance Program, opting for a more balanced geopolitical approach that emphasized neutrality. This shift culminated in the establishment of the Non-Aligned Movement, comprising countries not aligned with either power bloc. The improved relations also resulted in Soviet approval for credit for weapons purchases, enabling Yugoslavia to once again procure weapon systems from its preferred supplier. However, these sales contracts came with conditions, often obliging Yugoslavia to acquire obsolete weapon systems as a prerequisite for obtaining more modern equipment, such as T-55 tanks.

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Between 1961 and 1980, over 1,600 T-55 tanks were purchased, along with substantial stocks of older T-34/85 models. The latter decade of this period is often considered the golden age of the armored and mechanized formations of the JNA, as the constant inflow of new military equipment allowed for experimentation in unit organization and tactics. By this time, general overhauls and the production of most spare parts for the T-34s had been successfully established in the country. Predictably, an order was issued to initiate local production of spare parts for the T-55 as well, and an attempt was made to copy and locally produce the tank in its entirety, though the project was unsuccessful once again. This failure led the JNA leadership to recognize the need for foreign assistance in such matters. Consequently, it was decided to obtain a production license for a modern main battle tank as an intermediate step.

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Program “Kapela”

In August 1974, a meeting of the Federal Secretariat for National Defense took place to discuss the initiation of main battle tank production in Yugoslavia. Reflecting on previous unsuccessful attempts at domestic tank manufacturing, some members of the secretariat and representatives from the Military-Technical Institute (Vojnotehnički Institut – VTI) expressed reservations about this undertaking. However, representatives from the military-industrial complex, no doubt aware of the massive investments such a project would bring, were confident in their ability to successfully handle the challenge. The obsolescence of the Yugoslav People’s Army’s tank fleet, which still included 1,040 WWII-era T-34/85 tanks in the mid-1970s, and the urgent need for their replacement eventually forced the issue, leading to the inception of the Kapela (Chapel) project. As was tradition in Yugoslavia, military projects were named after rivers, mountains, cities, and animals. Project Kapela was named after a hill.

By the end of the following year, a task force comprising experts from the army and administration of the military-industrial complex was established to assess the readiness of the Yugoslav military industry for the task of domestic tank production. Once the license would be obtained, the Kapela team would transition to an oversight role, monitoring progress and serving as the final arbiter in any disputes or issues that arose.

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Which country should be approached for the license was hardly considered, given the Yugoslav People’s Army’s preference for Soviet gear, making the choice obvious. Similarly, selecting the tank to be licensed was a straightforward process. The T-55s were already obsolete, and the first 1,000 in the JNA were scheduled for decommissioning within a decade. The T-62s faced challenges in the export market due to their higher cost and maintenance requirements while offering comparatively little upgrade value over the T-55s. As a result, even Warsaw Pact countries, except for Bulgaria, opted out of the T-62. The decision was made to pursue a license for the newest T-72 main battle tank. However, there was a problem—the Soviet Union was not interested in selling it.

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Soviet Backbone

Though often touted as a cheaper, less sophisticated mobilization model of the T-64, the T-72 did not neatly fit that description and actually began its life as a modernization program for the T-64 main battle tank. After the failure of Object 167M program, Uralvagonzavod was allotted six T-64As to experiment with previously developed solutions, such as their own AZ ( Автомат Заряжания – Automatic Loader ) carousel-type autoloader, V-45K engine, and T-54-style cooling system. These modified T-64As were dubbed Object 172s. Once the reworked suspensions from Object 167 were incorporated into the project, the tank became known as the Object 172M. The prototype passed all state trials and was accepted into service in August 1973 as a T-72 “Ural”. The transition to the next major T-72 variant was gradual, with an interim model known as T-72 “Ural-1”, which entered service in 1975 and encompassed the majority of the early T-72 production run. These were the tanks presented to the Yugoslav delegation during their visit to the Vystrel military academy near Moscow.

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This delegation comprised members of the VTI, army officers, and representatives from the civilian industrial sector, who would be responsible for any theoretical tank production. They were welcomed by the head of the academy, Lieutenant General Davydov, who, along with his entourage, proceeded to introduce the delegation members to the new tank. Following a brief oral presentation, the delegation was permitted to enter the tank and ask questions, to which the elusive Soviets would, in turn, attempt to answer while revealing as little detail as possible. Subsequently, the delegation was guided through the academy’s classrooms and shown a training mock-up of a tank used during the class before concluding the visit with a dinner.

Although Soviet officers were not talkative and only basic characteristics of the tank were obtained, the delegation was nonetheless impressed by what they saw. However, there was also consensus that the Soviet construction quality was subpar, and some design solutions that were implemented were not particularly cutting-edge. Upon return, the delegation recommended that the license for the T-72 should be obtained, but any such talk was promptly shot down by the Soviet Government under the excuse that the licensed production of such a tank would be too complicated for Yugoslavia, and co-production agreements with Czechoslovakia and Poland were offered instead. Changing their minds required intervention from the boss himself, Marshal Josip Broz Tito, who, during his 1977 visit to the Soviet Union, personally negotiated the sale of the license with the Soviet General Secretary, Leonid Brezhnev, despite protests from the Soviet Defense Minister. Once the sale of the license was approved, there was another attempt to weigh down this contract with “unacceptable terms,” which once again required Tito to intervene. In the end, the production license was finally sold for US$39 million, though, like before, it came with certain conditions. The purchased license was valid for the next 10 years or the production of 1,000 tanks. The SFR Yugoslavia was not allowed to modify, sell, or co-produce the tank without the approval of the USSR, and some production models and components would have to be delivered to the USSR for testing.

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The T-72M export model, for which the license was bought, was an amalgamation of parts from the older “Urals” and the newest T-72A variant. The tank featured a 2A46 (D-81TM) 125 mm smoothbore main gun, 902A “Tucha” smoke launchers, rubber-mesh side-skirts, V-46-6 engine, and a 44-round ammunition capacity, all carried over from the T-72A. Only the older BM-9 and BM-12 APFSDS rounds were offered for the tank, as well as the older 80-105-20 armor layout without the composite filler in the turret.

The fire-control system was watered down, comprising the TPD-K1 stabilized gunner’s sight and a secondary separate TPN-1-49-23 night sight, a coincidence rangefinder and a ballistic computer. This fire-control system, as well as other electric systems and the tank’s mobility, were rated poorly by the VTI. Nevertheless, the T-72M represented a significant technological leap over the T-55, and the JNA asked for the licensed tank to be produced exactly as is, with modifications and upgrades being developed only after the successful start of the production. This request was dismissed by the VTI, which created a realization plan for the Kapela program including the provision to modify the license to address its shortcomings before the tank entered production. In October of 1980, the Kapela team approved the realization plan , and with this act, the M-84 tank was born.

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Twenty tonnes of the documentation for the tank arrived in the town of Subotica in mid-1979, transported via train in 40 freight carts. Before the tank production could commence, the extensive paperwork had to be thoroughly examined, translated and distributed by VTI to the hundreds of Yugoslavian companies vying for contracts. This process, which took years, involved both a meritocratic and a political approach, as the distribution of work among the republics was a sensitive issue. During a meeting held on this matter, representatives of the socialist republics that constituted Yugoslavia each presented their case for why their republic should receive the major share of the production contracts relating to the project. Representatives of the Socialist Republic (SR) of Slovenia even requested to be given the production of the tank in its entirety, citing the lack of involvement of their republic in the overall defense sector of the country. However, following the advice of JNA representatives, the Yugoslav government chose to pursue a balanced distribution of work among the constituent republics instead.

For example, three factories applied for the role of final assembly of all parts: Đuro Đaković from Slavonski Brod, Goša from Smederevska Palanka, and Mašinska Industrija from Niš. All of the applicants offered similar conditions, as they were all metal engineering plants and rolling stock manufacturers. Out of these, the Đuro Đakovic metal engineering factory was chosen due to its location in the Socialist Republic of Croatia, which was less involved in tank production compared to the SR Serbia, from where the other two competing companies originated. According to one analysis from 1992, the monetary value of each republic’s share in production was as follows:

Yugoslav RepublicContributing share in the value of the final product (%)
SR Bosnia and Herzegovina33.25% *
SR Serbia22.01%
SR Croatia21.73%
SR Slovenia17.93%
SR Macedonia3.39%
SR Montenegro1.69%

* – 14.67% of this value came from companies located within today’s Republic of Srpska, marked in light gray color on the map below.

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The SFR Yugoslavia stood out as a rare example of self-sufficiency in tank production, with nearly all components manufactured within the country. Only about 8% of the total cost for the production of a single tank came from the imports of materials and parts from abroad.
The bulk of the work was to be done by industrial giants of the SFR Yugoslavia, but in total, around 290 civilian factories, enterprises, companies, and firms were involved in the production of the tank. Each participant had to establish its own specialized department with a construction bureau in charge of drawing up the technological documentation and interpreting the construction documentation passed onto it by the VTI, while adhering to strict secrecy guidelines. Most participants approached the task with relentless optimism, promising timely deliveries, superb quality, and even pledging to develop their own design solutions superior to the Soviet ones. Those who were more honest with their capabilities risked being politically ostracized. This approach would later backfire, as companies that overestimated their capabilities struggled to start production, causing delays to the entire project.

The VTI begrudgingly accepted its role in the project, likely feeling that their talents as a research and development institution would be better spent on something other than copying a Soviet weapon. Nevertheless, they were placed in charge of the project development, verification of technological documentation, development of product quality regulations, and approval of modifications to the final product. TOC (Tehnički Opitni Centar – Technical Test Center) was in charge of testing the finished tank and determining its parameters.

Some of the major companies involved in production were:

  • Đuro Đaković – Slavonski Brod (SR Croatia): final assembly
  • Rudi Čajavec – Banja Luka (SR Bosnia and Herzegovina): fire-control system final assembly, ballistic computer, RUT-1 radio system, NBC (Nuclear, Biological, Chemical) protection, firefighting systems, and many other electronic components
  • Bratstvo – Travnik (SR Bosnia and Herzegovina): 2A46 125 mm main cannon
  • Pretis – Vogosca (SR Bosnia and Herzegovina): 125 mm ammunition
  • Zrak – Sarajevo (SR Bosnia and Herzegovina): day-night sights for the FCS, DNKS-2 commander’s sight, periscopes, andM87 anti-aircraft machine gun scope
  • FAMOS – Pale (SR Bosnia and Herzegovina): engine
  • FAMOS – Hrasnica (SR Bosnia and Herzegovina): M-84 transmission
  • RMK – Zenica (SR Bosnia and Herzegovina): turret bearings
  • 14th Oktobar – Krusevac (SR Serbia): M-84A transmission
  • Sever – Subotica (SR Serbia): autoloader
  • Rekord – Rakovica (SR Serbia): rubber parts of the tracks and running gear
  • Zastava – Kragujevac (SR Serbia): machine guns and small arms
  • Prvi Partizan – Uzice (SR Serbia): ammunition
  • Prva Petoletka – Trstenik (SR Serbia): hydraulics
  • 21 Maj – Rakovica (SR Serbia): manual turret traverse system
  • Sova, Ei Niš – Niš (SR Serbia): light amplifiers for aiming devices and periscopes (these were imported from abroad throughout most of the production run).
  • CEO Iskra (Fotona) – Ljubljana (SR Slovenia): laser rangefinder and other electronic components
  • Slovenske Železarne – Ravni (SR Slovenia): armor plates, turret, and metal parts of the tracks
  • Sava – (SR Slovenia): rubber screens
  • Metalski zavodi Tito – Skoplje (SR Macedonia): parts of the transmission
  • Aluminijumski kombinat Podgorica – Podgorica (SR Montenegro): wheels

Foreign Assistance

The task of distributing work to companies and factories was made harder by the fact that documentation arrived in Yugoslavia incomplete. While the construction documentation, which described individual tank parts and their properties, arrived in full, much of the technological documentation on the machinery and processes required for the production of parts listed in the construction documentation was missing. Some of the documentation, such as that concerning the NBC protection system, was deliberately omitted, as it was deemed too confidential to share, and the Soviet Union promised to supply these parts instead. The license provisions did not include technical assistance from the Soviet Union regarding the startup of production in Yugoslavia, and Yugoslav engineers were not allowed to visit Soviet tank production facilities.

Only a small team of instructors from the Soviet Union was dispatched to Yugoslavia in 1982 to help their engineers disassemble two T-72M tanks and answer questions during their short stay. However, this opportunity was wasted since the Soviet team arrived prematurely, before the Yugoslav engineers had even fully commenced the work on the project. This premature arrival left the engineers somewhat embarrassed, as they were not well-versed with the task and thus could not pose meaningful questions. Consequently, once the work actually commenced, Yugoslav engineers had to figure out most of the production process on their own. To find solutions, an engineering delegation was sent to Czechoslovakia.

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During the visit, the animosity between the Czechs, Slovaks, and the Soviets was exploited, as the Czechs and Slovaks were more than willing to assist with anything the Soviets would not. On one occasion, the Yugoslav delegation was invited to dinner at the home of the chief engineer of a Czechoslovak “Pal Magneton” tank factory located in the town of Kroměříž. During the dinner, the delegation members noticed that the engineer had a malfunctioning CRT television set, which they managed to repair. In gratitude, the chief engineer returned the favor by providing the delegation with all the documentation relating to tank production from the factory. Much of the documentation that was not granted through the license was obtained through similar methods, but all the components (the lower-right part of the drawing) were cut out because each document had an ownership number and confidentiality in that corner.

The days following the return of the delegation home were the most productive days of the entire project, as many problems regarding production and the new fire-control system in development were fixed. The production process was significantly aided by the ample utilization of the emerging field of informatics. Computers played a crucial role in monitoring the procurement of parts and the overall dynamics of tank production.

The Cost of Doing Business

Acquiring the license and establishing production proved to be an expensive affair for an already debt-ridden country. Beyond the initial US$39 million spent on the license, an additional US$7 million was allocated for processing, interpretation, and translation of the related documentation. Supporting infrastructure, factory modernization, tools procurement, and the creation of specialized tools for tank production required another US$121 million. An additional US$13 million were earmarked for the production of the M-84 tank prototype series. These combined expenses totaled US$180 million for the Kapela project. As per Dr. Prof. Milorad Dragojević, the Head of the Kapela project, the average production cost of an M-84 tank was estimated to be around US$700,000, which was nearly half the price of a T-72M.

Thanks to these substantial investments, the SFR Yugoslavia managed to commence mass production of main battle tanks, a feat few countries worldwide could accomplish at that time. The anticipated production rate was approximately 120 tanks per year. Studies conducted in the late seventies for the Kapela project indicated that the license purchase was justified, sensible, and cost-effective, even if the tanks were produced solely for the needs of the JNA, without factoring in potential export opportunities after completing the 1,000 tanks by 1995. The plan envisioned Yugoslavia breaking even after producing the 1,000th tank while retaining the benefits from the previous investments in the industrial sector. For example, many factories were re-equipped with expensive multipurpose machinery, which could later be used for projects beyond tank construction.

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The economic reality of the 1980s brought about stagnation, high unemployment, and international debt, pushing the Yugoslavian economy into a downward death spiral. Consequently, even before the first prototype was completed, Yugoslavia began marketing it to foreign buyers, with a particular focus on Libya.

Design of the M-84

Once all the paperwork was settled, earnest work on producing the first prototype could commence. In addition to the licensed documentation, one T-72M was delivered to Yugoslavia in 1979 to serve as a reference. Sometime later, two more T-72Ms arrived for testing, followed by a batch of a dozen more in 1981. These tanks underwent extensive testing to assess the compatibility of locally produced parts and to experiment with domestic upgrades, including a new fire-control system that would soon characterize M-84 tanks. Delays caused by the size and incompleteness of the delivered license paperwork meant the project fell behind schedule. Consequently, engineers assigned to the tank had to work under a lot of pressure, all while managing visits from both foreign envoys and domestic political commissions. In such conditions, the focus was put on rectifying the most visible issues first.

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The first tank from the prototype batch was ready in April 1983. At that time, due to the ongoing license conditions, the tank was designated T-72MJ. Like the rest of the prototype batch, this tank was a blend of foreign and domestic components and might have been largely based on one of the imported T-72Ms. Externally, the prototype closely resembled the early T-72Ms, with the most noticeable difference being the DNNS-2 aiming device from the SUV-M-84 fire-control system.

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SUV-M-84

The T-72M’s fire-control system (FCS) was deemed unsatisfactory from the outset, and the VTI began lobbying for its replacement as soon as the license was acquired. However, the heads of the army insisted on the prototype batch having an identical fire-control system to the T-72M, while work on the improved fire-control system would be done in parallel. When the costs of developing and producing two fire-control systems were presented to the Kapela group, the plan changed to ordering finished fire control systems for the prototype batch from the Soviet Union. However, it was discovered that the Soviets had already moved on to a better fire-control system and were refusing to supply it. Consequently, VTI’s proposal to remove the Soviet fire-control system was approved.

Fortunately, engineers had a suitable replacement in mind. Prior to the Kapela project, the JNA had initiated the modernization of its T-55 tanks through the Igman project, conducted in collaboration with the Swedish company Bofors. This endeavor led to the development of the SUV-T-55 (Sistem Upravljanja Vatrom – Fire-Control System). Although the serial modernization of the JNA’s T-55s never commenced, and only about 10 T-55s were modified with the new fire-control system, technological and construction documentation for the components of the fire-control system were available and could be reused for the new M-84 tank. As the license for the fire-control system was exclusively granted for the T-55 tanks, the installation of the systems on the new domestic MBT was carried out with utmost secrecy. Production of the components for the fire-control system was entrusted to the Rudi Čajavec company in SR Bosnia and Herzegovina.

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With the hardware for the fire-control system settled, new software for the system also had to be developed. While Project Igman was on the back burner, the software for it, previously stolen by the Yugoslav secret service from the Volvo car of Bofors employees, was unfortunately unusable as it was booby-trapped with hard-to-detect malware code, rendering it inaccurate in practice. Consequently, VTI and Rudi Čajavec were both tasked with writing the new software from scratch. As VTI was also in charge of choosing a winning software, it chose its own, and once their software was merged with the available hardware, the SUV-M-84 fire-control system for the new tank was ready.

The most important component of the fire-control system was the gunner’s independent DNNS-2 combined sight, replacing the previously separate TPD-K1 day sight and TPN-1-49-23 night sight. The new sight was designed to be compatible with the T-72M turret, enabling its retrofit into these tanks without modifying the base.

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The DNNS-2 features three-plane stabilization and three channels for the gunner: day, night, and a laser channel for the rangefinder. The day channel offers a magnification of x3, providing a 20° field of view, and x7, granting a 9° field of view. The night channel is capable of x8.5 magnification, allowing the gunner a 5.4° field of view. On a moonless night, the DNNS-2 can detect targets at 1,500 m and identify them at 1,200 m. Accurate fire can be opened at 1,000 m if the tank is stationary. The laser rangefinder can measure distances to targets within the range of 200 to 9999 m.

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The DNNS-2 was designed with the ability to be paired with a camera providing a live feed (albeit in black and white, as cameras in the 1980s were not very advanced) to the commander inside the tank or personnel outside of it. Though envisioned for training purposes, this system not only allows immediate insight into the crew’s shooting procedures with real-time correction via a radio link during training but, in theory, if paired with a command vehicle, it could also enable the live monitoring of an effect on target during the engagement from a command center.

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While the tank is on the march, the gunner’s DNNS-2 aiming device is usually covered by a protective cap, which can be lowered from inside the tank using a somewhat flimsy cable designed under pressure. Because of it, the cable is prone to deformation and snapping, leading to the redesign of the lowering mechanism in later M-84AB export variants.

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The initial version of the DNNS-2 gunner’s aiming device had only first-generation night vision equipment. Consequently, tanks equipped with this sight also had two IR headlights, which contributed to the picture quality, but the aiming device could still be used without them. Starting with the second production series, DNNS-2 devices were equipped with second-generation night vision equipment, rendering the IR headlights somewhat redundant. Hence, they were removed.

Although this gunner’s aiming device was satisfactory, ongoing development led to the introduction of an updated DNNS-2A aiming device together with the M-84A tanks. In comparison to the DNNS-2, which featured either first or second-generation night vision capabilities powered by a voltage of 6.5 volts, the DNNS-2A incorporated second+ generation image intensifiers powered by 2.65 volts. It is important to note that these two systems are not fully interchangeable and require different amplifier boxes which look the same but provide different voltage output. The easiest way to differentiate which aiming device is mounted is to check the gunner’s panel. First, older DNNS-2 panels only have a simple “Night Channel” on-off switch, while the DNNS-2A panels have a rotary potentiometer for image adjustment in its place.

The M-84AB tanks destined for Kuwait were equipped with their own DNNS-2A/6400 aiming device, featuring a distinct reticle and a key in place of a switch for turning on the laser. Due to a different method of rounding up the Pi number, Warsaw Pact and Yugoslavian sights featured 6,000 milliradians as opposed to 6,400 as used by the West, and as requested by Kuwait for their own tanks.

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There were plans for further development, culminating in the DNNS-2TI, which included thermal vision and was expected to complete all tests and enter production in following years. Unfortunately, due to the war and the subsequent breakup of the state, all future development came to a halt.
The Serbian M-84AS1 (2017) prototype was equipped with a DNNS-2ATK sight, which is said to have a thermal imager. As this modernization package was not put into production, little else is known about it, but it is likely that the sight mounted was actually the previously developed DNNS-2TI.

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Finally, there was a downgraded wartime version of the aiming device, designated DNNS-R. This device lacked the x3 and x7 zoom options and was produced only with parts already available at Zrak (Sarajevo) during the civil war in Bosnia and Herzegovina. It is unknown if any were ever mounted on the M-84 tanks, but one found in the warehouse was later mounted on the command version of the M-80 infantry fighting vehicle (IFV). This command IFV is currently in service with the Armed Forces of Bosnia and Herzegovina.

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The TKN-3 commander’s sight from the T-72M was replaced with the domestic DNKS-2 commander’s sight. The DNKS-2 comes equipped with both day and night channels, offering a wide operational range of 360° horizontally and -8° to 12° vertically. In the day channel, the sight provides a magnification of x4.9 with a field of view of 10°, while the night channel features a passive image intensifier, delivering a magnification of x4.3 and a field of view of 10.9. During use, the commander manually rotates his cupola, in which the sight is embedded, utilizing it for fire correction or independent target acquisition. Like on the T-72M, the commander can horizontally rotate the turret in the same direction as his DNKS-2 device, although he cannot engage targets by himself. Instead, the gunner would need to vertically guide the gun onto the target before opening fire.

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A ballistic computer is employed to compute the elevation and azimuth (pitch and yaw axes) angles of the main cannon based on the data collected by the 4 KB microprocessor, including:

  • longitudinal and lateral inclination of the tank
  • the engagement distance and the speed of the target, gathered via the laser
  • available meteorological information gathered by the meteorological sensor at the top of the tank
  • the type of ammunition used, noted via a switch on the ballistic computer’s control panel
  • gunpowder temperature, collected by the sensor located in the commander’s panel

The FCS computer can calculate firing solutions for subcaliber and cumulative projectiles at distances from 200 to 4,000 m, high-explosive projectiles from 200 to 9,400 m, and the PKT coaxial machine gun from 200 to 1,500 m.

The fire-control system of the early M-84 tanks featured the A20X (MBL) meteorological sensor manufactured by the Swiss company Geotec, which provided information on wind speed, atmospheric pressure, and air temperature. Some parameters, like air density or humidity, were not recorded because their impact on the projectile accuracy was considered negligible. These sensors were capable of detecting longitudinal wind speed and crosswind of up to 40 m per second. On the prototype and zero series tanks, A20X (MBL) sensors were placed on a short carrying arm with a rubber damper, while on the first series tanks, they were known as A20X (MB) and were mounted on the longer, folding carrier arm.

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During testing, it was observed that the impact of longitudinal wind on accuracy was less pronounced on the M-84 tanks, thanks to their better-stabilized and faster projectiles, compared to the modernized T-55s from which the initial meteorological sensors were adapted. As such, starting with the second series, the A20X sensors were replaced by the simpler and more affordable A10X (MB) sensors which could not measure longitudinal wind and which were capable of measuring crosswind of up to 25 mps. The two sensor types were not fully interchangeable, and switching from one to the other required adjustments to the software of the ballistics computer. Since the new A10X (MB) sensors were somewhat bigger, a new telescopic mount with a rubber cap was designed by VTI.

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The design of the new meteo-sensor incorporated a retracting mechanism utilizing a rubber cable inside a coil spring, making the whole system susceptible to getting jammed if mishandled. When pulled, the cable would lower the meteo-sensor via the coil spring, but sometimes the cable would get stuck between the coils, leading to the damaging or snapping of the cable, leaving the meteo-sensor protruding outside the telescopic carrier. Furthermore, if the insulation of another cable present in the coil, SUV cable number 7, was damaged, rainwater could enter it and slide down to the commander’s panel, causing further damage.

Another problem was identified with the protective rubber cap on top of the telescopic carrier. This cap increased the atmospheric pressure inside it to levels beyond what the sensor could handle, resulting in the failure of hundreds of these sensors shortly after the introduction of the second and third series tanks. Since VTI was refusing to accept the responsibility but hundreds of sensors still had to be repaired, blame was shifted to Geotec for supplying supposedly subpar products. A substantial batch of damaged sensors was returned to Geotec for overhaul, accompanied by a delegation from VTI, including members from the Zemun Institute of Physics. During their visit, the delegation gained insights into the production process. Following their return, production of domestic copies of these sensors, designated MS1 and MS2, was initiated.

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Regrettably, this telescopic meteo-sensor design remained unchanged until the sixth series of M-84AB tanks for Kuwait. Even today, meteo-sensors remain a frequent source of breakdowns for M-84 tanks in Serbia and Bosnia and Herzegovina. In contrast, Croatia and Slovenia have taken measures to modify these sensor carriers, likely in an effort to address the longstanding bugs and enhance their reliability. Luckily, in case of a malfunctioning meteorological sensor, data can still be manually typed into the ballistics computer.

The gunner has over a hundred switches, buttons, levers, water and air valves, and similar controls which enable a robust system of backup modes of operation, considering the systems on the tank that may have been damaged, disabled, or destroyed. An analogue mode of operation exists in case there is no electricity in the tank at all. This ensures that there is always a possibility of deriving some use from the intact parts of the tank, even if other parts are defective.

The SUV-M-84 was an effective fire-control system for its time. Once all the bugs were ironed out, the FCS showed impressive accuracy during domestic tests and trials conducted in foreign countries. In a comprehensive evaluation conducted alongside a T-72M tank, the M-84 was judged to be two to three times more precise than its Soviet counterpart. Live-fire demonstrations in Pakistan and Indian tests of the SUV-M-84, modified to fit on a T-55 tank, also left very good impressions. In Kuwait, M-84AB tanks often outperformed the M1A1 Abrams tanks in terms of accuracy during joint exercises. When the M1A1s were particularly under-performing, the exercises were prone to getting abruptly canceled.

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Soviet Pot, Yugoslav Kettle

Differences between the T-72 and M-84 were somewhat more pronounced from inside the tank. The replacement of the old fire-control system necessitated the removal of both gunners’ aiming devices and a commander’s sight, and their subsequent substitution with the domestic systems. Nearly all original Soviet electronics were also swapped, including the radio equipment and intercom, an antenna mount and antenna, the stabilization system and the three-phase voltage converter. The NBC protection system, fire extinguishing system, and voltage regulator were also replaced with domestic components made by the Rudi Čajavec company. This was done both because domestically available electronics were superior and due to the incomplete Soviet documentation, particularly concerning all electric systems, making their replacement essentially necessary. The turret bearings also had to be lightly modified, making M-84 turrets incompatible with other T-72M tanks in service with the JNA without an overhaul.

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A number of parts from the T-72M that lost their function with the new modernization were removed. One such part was the linear accelerometer, which used to be located in front of the commander. This tool was used to give the stabilizer additional power, which was used to spin the turret in cases where extra effort was required, such as when the tank sat on a sharp slope. The M-84 had a different solution for supplying power to the stabilizer, thus the linear accelerometer was removed. Another one is the cosine potentiometer, intended for calculating the speed of rounds during firing. However, this part was never connected to the system and started being removed from the second series onwards.

Curiously, some other parts were never removed despite them losing their function, such as the holder of the high-voltage probe for TPN-1-49-23 night sight, gunner’s fuse board and various protrusions on the 125 mm gun which were a part of the stabilization system on the T-72M.

The frontal mudguards include four holes, allowing for so-called “gill” armor to be mounted on the tank. This type of protection was, however, never serially installed on M-84 tanks due to the introduction of rubber side skirts, making the holes an unnecessary leftover from a T-72 tank as well.

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Main Armament

The M-84 tank’s main armament is the 2A46 (also known as D-81TM) 125 mm L48 smoothbore cannon. This gun was developed by the OKB-9 Design Bureau from Sverdlovsk (now Ekaterinburg) as a modernization of the older 2A26M model. The most notable improvement was the implementation of a hydraulic recoil buffer fluid expansion compensatory mechanism, departing from the fluid-air mixture used in the 2A26. This design change resulted in a more even recoil stroke, enhancing the dynamic motion of the round inside the gun barrel and, consequently, improving firing accuracy. In Yugoslavia, cannons were produced by the MKK Bratstvo factory located in Novi Travnik, SR Bosnia and Herzegovina. When guns are subjected to prolonged exposure to the sun, the top part of the barrel facing the sun expands faster than the bottom part in the shade. To address this, the barrels are wrapped in thermal insulation linings made from tin.

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The 2A46 gun on the M-84 tank is 6.12 m long, with 5.11 m protruding out of the turret. It has a maximum gun depression of -6°13′ and elevation of 13°47′. The rounds are typically loaded into the barrel by the carousel AZ autoloader at a speed of 8 rounds per minute, but the gun can also be manually loaded, reducing the fire rate to around 2 rounds per minute. The autoloader on the tank is an electromechanical carousel-type with a 22-round capacity. All 22 rounds are stored in individual cassettes arranged radially around a central hub that houses the carousel rotation motor, drive, and the power supply for the turret. However, this design is susceptible to catastrophic failure if the ammunition in the carousel is detonated, such as in the event of a direct hit or a larger anti-tank mine explosion. The autoloader relies on a carousel storage memory unit to identify the position of each round within the carousel and determine the status of each cassette, whether it is empty or not. The carousel can spin at two different speeds. It spins at maximum speed until the required round is two cassettes away from the loading position. At this point, it changes to a slower rotating speed.

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Turret rotation speed can range from 0.07° to 18°/s, and gun elevation speed ranges from 0.05°/s to 3.6°/s. If the turret is rotated and the gun barrel protrudes over the side of the tank, the driver is notified via two lights in his periscope. This allows him to estimate the amount of space needed to allocate to the left or right of the tank to avoid damaging the barrel while driving. Additionally, the driver can force the turret rotation with a switch “Akvizicija Vozača” (Driver’s Acquisition) to the left of his periscope in case the gun barrel is blocking his escape hatch.

During marches, the turret is usually locked with the gun pointing slightly to the right of the tank. This is done to avoid unnecessary inertial swinging of the turret during the tank’s movement, which can damage the rotation mechanism or injure the crew inside.

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To fire, the tank has to complete the preliminary and immediate preparation. Preliminary preparation is done before the combat and includes:

  • preparation of weapons and aiming devices
  • ammunition preparation
  • determining ballistic and meteorological conditions
  • terrain study, selection of landmarks, and determination of the distance to individual lines, points and local facilities, and
  • preparation of the crew

Immediate preparation is the firing procedure, and it includes:

  • target Identification: the gunner identifies the target and assesses its distance, direction and speed
  • target acquisition: the gunner places the chosen target in his sight. In case any part of the system is malfunctioning, spare reticles can be employed as an alternative
  • ammunition Selection: the gunner chooses the type of ammunition to be used
  • loading: the autoloader loads the selected projectile into the breach of the main cannon
  • target lasering: the gunner chooses the firing mode, and measures the distance to the target using a laser
  • lead angle adjustment: if either the target or the tank is moving, the gunner activates the “Lead Angle” feature to account for the movement
  • issuing the fire command: fire!
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The loading process of the autoloader, with some overlap between the steps, is as follows:

  • the gunner selects an ammunition type on his selector dial and presses the “load” button
  • the gun moves to the loading angle, and simultaneously, the stub catcher is raised to eject the stub casing from the previous shot
  • the carousel spins until it reaches a cassette containing a cartridge of the selected ammunition type
  • the cannon vertically moves to the loading position and then gets mechanically locked in place
  • the carousel stops when the cassette is directly under the elevator
  • the elevator lifts the cassette to ramming position No. 1, positioning the projectile behind the breech
  • the power rammer extends to ram the projectile and retracts
  • the elevator lowers the cassette to ramming position No. 2, positioning the propellant behind the breech
  • the power rammer extends to ram in the propellant charge and retracts
  • the elevator lowers the cassette back into the carousel, and the memory unit marks the cassette as empty

The barrel life of the gun is poor, and influenced by the type of ammunition used. APFSDS-T (Armor-Piercing Fin-Stabilized Discarding Sabot Tracer) ammunition wears out the barrel fastest, requiring only 250 rounds. Approximately 900 to 1,000 HE-FRAG (High-Explosive Fragmentation) and HEAT-T (High-Explosive Anti-Tank Tracer) rounds can be fired before the cannon diameter expands to 127.5 mm, making it unusable. For each 0.1 mm diameter expansion, the initial speed of the HE-FRAG round drops by 2.7 m/s. Once the projectile speed sufficiently drops due to cannon wear or inadequate cleaning, there is a growing risk of permanent barrel deformation because of the additional pressure exerted by a decelerated round. Rounds are also prone to getting stuck in the breach or between the gun trunnions during the recoil cycle, putting the entire tank and its crew at risk.

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All tank rounds feature a copper ring designed to seal the gaps between the round and the barrel, preventing the combusted propellant gasses from escaping around the loaded round regardless of the barrel wear (caliber size). After firing several rounds, these rings would leave a copper layer inside the gun, which then must be cleaned to prevent the interior of the gun from becoming deformed. Although the cleaning process is unpleasant and emits a strong odor, it is an unavoidable step in tank maintenance to ensure the gun’s continued functionality. Regrettably, proper gun maintenance and cleaning were neglected during the civil wars in Yugoslavia. Consequently, the explosion of the tank barrel due to poor maintenance emerged as one of the most common reasons for the loss of a tank. In one such incident, a round exploded in the gun breach, launching the barrel 30 m ahead of the tank. Fortunately, the crew suffered only minor injuries.

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Secondary Armament

For close-range anti-infantry purposes, the tank is equipped with a Zastava M86 7.62 mm machine gun in a coaxial mount to the right of the main gun. This licensed copy of the Soviet PKT has an effective range of 600 m against individual targets and 800 m against groups of targets. The theoretical rate of fire is 650-750 rounds per minute, but in practice, it is closer to 250 rounds per minute. The machine gun’s standard loadout consists of eight belts of 250 rounds.

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Additionally, the commander’s cupola is armed with the Zastava M87 12.7 mm Heavy Anti-Aircraft machine gun. This licensed copy of the Soviet NSVT machine gun, equipped with the domestic K10-T sight, can engage air targets up to 1,500 m and ground targets up to 2,000 m away. The machine gun has a full 360° rotation capability independent of the commander’s cupola, with a maximum depression of -5° and elevation of 75°. The theoretical rate of fire is 800 rounds per minute, but in battle conditions, the practical rate of fire is usually around 150 rounds per minute. The typical loadout consists of five to six belts of 60 rounds.

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Ammunition

Due to the placement of the new ballistic computer and amplifier box in the tank, the number of rounds in the tank’s turret had to be reduced by one compared to the T-72M. Thus, the standard loadout for the M-84 was 43 rounds, 22 of which would be located in the autoloader’s carousel and the rest in the tank’s turret. SFR Yugoslavia was granted license production of three types of rounds: APFSDS-T, HEAT-T, and HE-FRAG. All rounds are two-piece, with a separate powder charge that is identical for all projectile types.

The ballistic computer firing table allows APFSDS-T and HEAT-T rounds to be fired at distances of up to 4,000 m, and HE-FRAG rounds at distances of up to 9,400 m. If the gun barrel moves up above 59 thousand milliradians, the tank enters indirect fire mode, and a topographical map has to be used while firing.

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The standard round for engaging enemy armor is the Armor-Piercing Fin-Stabilized Discarding Sabot Tracer (APFSDS-T) 3BM-9 / 3BM-12 round. The only difference between the 3BM-9 and 3BM-12 rounds was that the 3BM-12 had a tungsten carbide plug, making it slightly longer. These two rounds are used interchangeably. Thanks to their initial speed of 1,800 m/s (~4,000 mph), this type of round is able to punch through 290-350 mm of hom*ogeneous steel armor placed at 0° at 2 km (1.2 miles). At 150 m (~500 feet) after firing, the sabot would discard, leaving the steel dart penetrator stabilized by the fins.

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The ballistic computer’s firing table for this type of round was made for targets located as far as 4,000 m (2.5 miles), but in practice, the round can fly much further. In Yugoslavia, live fire of this type of round was allowed only at the Kalinovik training field, due to the high chances of ricochet and therefore collateral damage when this type of round is used. In service, these rounds were designated PKO M88 and PKO-J M88 and referred to as Potkalibarna (Subcaliber).

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When the APFSDS-T does not cut it, there is a High-Explosive Anti-Tank Tracer 3BK-14 (HEAT-T) round. Though flying at half the speed of an APFSDS-T round, HEAT-T has better penetration capabilities, being able to defeat 500 mm of hom*ogeneous steel armor placed at 0° at 2 km. This round is especially suitable for far away armored targets, as its penetrative capabilities do not diminish with distance, at the cost of longer travel time and worse accuracy. In service, this round is designated KOP M88 and referred to as Kumulativna (Cumulative).

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The High-Explosive Fragmentation (HE-FRAG) round is used against everything else, including infantry, bunkers, unarmored vehicles, and other soft targets. These rounds can be set to explode on impact or with a delayed fuze via switch and the rotating cap at the top of the warhead. HE-FRAG is the cheapest type of round, costing around US$2500 in the mid-1980s (equivalent to around US$7,165 nowadays). As such, live fire training and exercises are usually conducted with these rounds. The firing table in the ballistics computer allows for this round to be fired at targets located up to 6 km (3.7 miles), though in practice, it could be manually fired at targets twice as far. Indirect fire, akin to self-propelled artillery, is not viable with this projectile, as it is prone to spinning out on the vertical axis when fired at a high arc. In service, this round is designated TFP M86 and referred to as Trenutno-Fugasna or Razorna (Instantaneous-Explosive or Destructive).

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In certain scenarios, usually while testing the recoil mechanism of the gun, live fire can be simulated by using a powder charge and an amount of water equivalent to the weight of the round. This practice also allows crews to go through the motions of firing without expending actual ammunition.

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The standard ammunition loadout depended on the mission profile. Infantry support missions often required a higher proportion of HE-FRAG rounds loaded, whereas a theoretical ambush mission in which the tank would go up against a column of enemy armored vehicles would require a larger percentage of anti-armor rounds. The gunner had to take into account and manually select in the ballistic computer which ammunition type was being loaded, as different ammunition types required different ballistic settings. There was an attempt to update the loading mechanism of the tanks to take into account which round is being loaded automatically, though this work remains uncompleted, and only some of the tanks have their hardware modified in such a way.

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Of the 43 rounds, tanks were doctrinally expected to carry:

  • 20 M86 HE-FRAG rounds (10 in the autoloader’s carousel)
  • 16 PKO/PKO-J M88 APFSDS-T rounds (8 in the autoloader’s carousel)
  • 7 KOP M88 HEAT-T rounds (4 in the autoloader’s carousel)

In practice, during the Yugoslav Wars, the tanks were loaded with whichever ammunition was available at the moment, and HE-FRAG rounds were used the most.

The development of ammunition has continued in Serbia, where new 125 mm subcaliber, training, and canister rounds have been developed. As 125 mm ammunition continues being manufactured only in Serbia, Slovenian, and Croatian M-84s are currently using ammunition imported from Eastern European countries such as Ukraine.

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Protection

The M-84 tank’s armor, built according to the license and identical to the T-72M tanks, features a hull composed of welded plates. The front glacis is set at an angle of 68° (with an above obliquity of 22°), and is the only section made out of composite materials. This design comprises two layers of rolled hom*ogeneous steel (RHA) plates with a layer of glass-reinforced plastic material known as textolite in between. The front-most RHA plate is 80 mm thick, while the second plate is 20 mm and serves both as support for the glass textolite layer to prevent delamination and as a final defense against kinetic penetrators. The textolite layer between the two RHA plates serves as an anti-shaped charge filler, and is 105 mm thick. This 80-105-20 armor layout is recognizable by the four anti-ricochet “ribs” in front of the driver’s periscope. This armor configuration provided the tank with protection equivalent to 305 to 330 mm of Rolled hom*ogeneous Armor (RHA) against APDS, or 450 mm of RHA against shaped charges.

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The V-shaped mudguard is present on the upper front plate, and the lower front plate has a dozer blade attached for the tank to dig itself in. The process of digging a tank trench can take anywhere between 10 and 40 minutes, influenced by ground conditions such as soil hardness. During this operation, the commander typically guides the driver using hand gestures or signal flags from outside the tank. The trench is typically dug to a depth that reaches the roof of the hull, leaving only the turret protruding outside of it.

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The 12-tonne turret, constructed from cast hom*ogeneous steel, has an estimated maximum thickness of 410 mm, with the machine gun port and gun mantlet area potentially reaching thicknesses of up to 475 mm. The turret cheeks become progressively thinner towards the rear, but effective thickness from the front remains similar due to its rounded shape. Roof armor is 45 mm thick, with the part above the gun breech being perhaps twice as thick. Due to the roof being set at an angle between 78° and 80°, it provides effective thickness of around 210 mm from the front, though the steep slope is likely to cause most offending projectiles to ricochet.

In summary, the frontal armor of the M-84 was largely immune to early 105 mm APDS and HEAT rounds, as well as light shoulder-fired HEAT grenades, although it was considered dated by the second half of the 1980s, when the M-84 tank first entered service.

Soviet testing of the 80-105-20 armor layout eventually revealed structural deficiencies in the thin back plate when faced with long rod penetrators. Subsequent testing aimed at eliminating this deficiency showed that the thickness of the frontmost plate could be reduced to 60 mm, the minimal thickness required to disrupt a shaped charge jet, while the thickness of the rearmost plate could be increased to 50 mm, improving performance against newer APDS ammunition. This armor layout, consisting of a 60 mm RHA plate + 105 mm textolite layer + 50 mm RHA plate, began to be implemented on late Ural-1 T-72s before becoming standard on T-72As. Protection against APDS projectiles was increased to 360 – 400 mm of RHA, and against shaped charge projectiles, it was elevated to the equivalent of 490 – 500 mm of RHA.

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After capturing and testing the Israeli M111 “Hetz” ammunition, it was discovered that the front plate of the T-72 tanks is still vulnerable to 105 mm guns. The stopgap solution developed by the Soviets was the addition of 16 mm high hardness appliqué armor to the front plate. The physical thickness of the armor array was thus increased to 231 mm, and the effective thickness was increased to 617 mm. This updated armor layout did not fully protect the tank from the newest 105 mm ammunition and new 120 mm guns fielded by the West, but it certainly improved its odds of stopping the enemy projectiles at long ranges. The effective armor thickness against the M111 APFSDS projectile was increased to the equivalent of around 430 mm of RHA.

The turret of the tank also saw an upgrade with a composite, sand-like material being added to the cavities in its cheeks. As the new turret became a three-layer sandwich like the upper front glacis, the shape of it also changed, with the maximal physical thickness now being close to 540 mm, of which 115 mm is the composite material in cheeks. The composition of this material has not yet been declassified, so its exact effectiveness is hard to estimate. The reason it was added to the turret was to increase its protection against shaped charges, providing the tank with 500 mm equivalent of RHA protection against HEAT warheads. Against APFSDS rounds however, the protection remained nearly the same as the old hom*ogenous turret, rated at around 410 mm of RHA.

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Eventually, these armor upgrades, in the form of the T-72M1 license, were offered for sale to the T-72M license holders, including SFR Yugoslavia in the second half of the 1980s, priced at US$7,000,000. This cost was deemed excessive for an optional, simple upgrade of the armor protection, which was already considered satisfactory. Yugoslav engineers asserted they could implement this upgrade without purchasing the license. However, in the spirit of camaraderie, it was proposed to exchange the T-72M1 license rights for the SUV-M-84, one example of which had previously been sold to the Soviet Union along with one M-84 tank. The Soviet side agreed to this arrangement, and the T-72M1 license was transferred to Yugoslavia.

A subsequent order was issued to incorporate the upgraded armor layout into the M-84 tank and begin production of the updated M-84A tank by March 1988.

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The side armor of the M-84 tanks consisted of 80 mm rolled hom*ogeneous steel (RHA) plates, providing a mediocre level of protection. The rear armor, slightly thinner, measured 70 mm in thickness. To enhance protection against shaped charges, the tank featured 10 mm wide side skirts made of synthetic rubber reinforced with polymer fabric and steel wire mesh. However, it is noted that these skirts might not be entirely effective, as 67 mm M80 Zolja portable one-shot anti-tank launchers were known to cut right through them. In addition to their primary role in protection, the skirts on the M-84 tank served a secondary purpose by shielding the engine air intake from the dirt and dust kicked up by the tracks.

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What helps the side protection somewhat is the small silhouette and low profile of the tank. The side profile is notably compact, with a surface area 2.5 m² smaller than that of the M1A1. With a height of only 2.19 m, a length including the gun of 9.53 m, a length of the body (excluding the gun) of 6.96 m, and a width of 3.46 m, the M-84 achieved its compact dimensions largely thanks to the replacement of the fourth crew member with an autoloader.

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To further enhance their defensive capabilities, the tanks were equipped with the 902A “Tucha” smoke grenade launchers. The layout of these launchers on the turret serves as a key differentiator between major variants of the M-84 tank:

  • the zero to fourth series M-84 tanks featured 5 launchers in the “U” layout on the right side of the turret, with another 7 launchers on the left side
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  • M-84As had two sets of 6 launchers symmetrically placed in lines on both sides of the turret
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  • M-84AB tanks designed for Kuwait had 5 launchers in the “L” layout on the right side of the turret, with another 7 launchers on the left side.
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The “Tucha” smoke grenade launchers can create a smoke screen 150 m in front of the tank, with an adjustable width ranging between 15 and 110 m. Once fired, the smoke grenades start generating smoke within 10-12 seconds, lasting for 3.5 to 5 minutes. The gunner operates the smoke grenade launcher.

Additionally, the tank can deploy smoke without the use of Tucha system by injecting diesel fuel into the exhaust manifold, which produces a thick white smoke on the right side of the tank. This alternative method is initiated by the driver, who has to flip and hold a switch. However, deploying smoke in this manner increased the tank’s fuel consumption by an additional 10 liters per minute.

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Engine and Transmission

Most versions of the M-84 tank are propelled by the licenced V-46-6 V-12 four-stroke diesel engine, generating 780 hp (574 kW) at 2,000 RPM. At the time of its adoption by the JNA, this was considered to be barely acceptable for a modern vehicle, at just 13.8 kW/t (18.7 hp/t). The engine allowed the 41.5-tonne tank to achieve a nominal top speed of 60 km/h on asphalt and maintain an average speed of 35 to 40 km/h on dirt roads.

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The engine is multi-fuel capable, accommodating low octane gasoline (A-66 and A-72), standard Soviet military-grade diesels, kerosene (TS-1, T-1, and T-2), and petroleum naphtha (paint thinner). However, using petrol or kerosene results in a power decrease of up to 20%. Fuel consumption ranges between 260 and 450 liters per 100 km, offering a travel range of 460 to 700 km on a single refueling, depending on the terrain. The fuel tanks of the M-84 have a capacity of 1,200 liters, which can be increased to the maximum of 1,600 liters by adding two 200-liter barrels behind the tank. M-84A tanks carry 150 liters less due to a modified external fuel tank arrangement.

To facilitate winter starts, the engine features a heater activated at outside temperatures below +5°C. Despite its advantages, the V-46 engine is noted for its relatively high specific oil consumption due to larger clearances in the cylinder group.

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In response to concerns about engine performance and its effect on potential exports and development of the new domestic tank, a decision was made to modify the engine to improve its capabilities. Studies of the problem began in 1980, and actual work began in 1983, resulting in the development of the V-46-TK engine (TK being short for Turbokompresor – Turbocharger) capable of producing 735 kW (1,000 hp). This improved power output was achieved through the removal of the centrifugal compressor, where two S4 Schwitzer turbochargers with an intercooler have been installed instead. The high pressure pump and the combustion chambers also had to be modified. The V-46-TK engine, while operating under increased strain, experienced a reduction in reserve torque, which negatively impacted the tank’s mobility and maneuverability in challenging terrain. Despite this, the new engine represented a significant achievement, and there was eager anticipation for its practical testing and production by the VTI’s young team that designed it. The V-46-TK engine underwent initial testing in the factory, running for 500 hours without encountering any issues. Subsequently, one M-84 tank was equipped with the engine and tested alongside a T-72M. The results of the test indicated that the modified M-84 exhibited an average speed increase of 30%, lower engine noise, and a temperature reduction of 10°C in the engine cooling liquid, though the final point seems to be contested. The results were considered a huge success, as Yugoslav engineers were able to upgrade the engine years ahead of the Soviet Union’s development of a comparable engine. The V-46-TK was approved to enter production in 1988. However, delays with the M-84A tank project meant that these engines would not enter service until 1991, with the first and only shipment of these tanks to the JNA. In Yugoslavia, all engines were produced by FAMOS from Pale, SR Bosnia and Herzegovina. As this factory had the capacity to produce more engines than required for the Kapela project, around 2,000 engines were also produced for the Soviets, who were very pleased with their quality.

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The tank’s transmission is mechanical, utilizing dual planetary gearboxes with hydraulic control. The gearboxes incorporate seven gears for forward movement but only one for reverse, severely limiting the tank’s speed in reverse. Thanks to this limitation, the transmission is cheap, light, compact, and reliable. The M-84’s transmission, with its dual gearboxes, enables the tank to achieve various turning radii depending on the selected gear. According to the Tankograd blog, the turning radii of the comparable T-72 tank are as follows:

GearTurn radius (m)
R2.97
12.97
26.04
313.42
413.93
510.23
610.1
78.76

The M-84 can steer by slowing down one track, de-clutching one track, or with a combination of de-clutching and braking, which is done only in the first gear or reverse.

Suspension

The M-84 features independent suspension using full-length torsion bars, with each bar running across the entire width of the hull. The first, second, and sixth wheels are reinforced with hydraulic shock absorbers. The running gear comprises a sprocket in the back and an idler wheel in the front, along with three return rollers and six evenly spaced road wheels per side. These 8-spoked road wheels are made of aluminum to reduce weight and decrease rolling resistance. The tracks are metal, measuring 580 mm wide, and consist of 96 links connected by rubber-metal hinges.

As per Kuwaiti request, these tracks would be replaced with a new type, capable of mounting rubber pads for improved performance on paved surfaces. Most of these were shipped off to Kuwait together with M-84AB tanks, but limited numbers remain in use with other countries.

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The M-84 tank is capable of climbing obstacles up to 0.85 m tall with its mudguards on. When the mudguards are removed, its climbing ability improves further. However, these mudguards, made of sheet metal, are prone to bending and deforming if a large amount of mud accumulates underneath them. Consequently, they were often removed during use in the Yugoslav Wars. Additionally, the M-84 tanks can overcome trenches up to 2.8 m wide and can traverse ascents of up to 30° and side slopes of 25°.

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Without any preparation, the tank is capable of driving through water up to a depth of 1.2 m. With minimal preparation, water obstacles of a depth of 1.8 m can be overcome. For larger water obstacles, the tank is equipped with a deep water fording kit, allowing it to traverse depths of up to 5 m over a length of up to 1 km at a speed of 5 km/h. This maneuver is one of the most challenging tasks a tank platoon could be asked to perform, as even the slightest error could leave them stranded at the bottom. Therefore, this practice is prohibited during night and poor weather conditions, and the tanks are always assisted by divers and an armored recovery vehicle.

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Since the tank is not hermetically sealed, it is equipped with a pump that removes water throughout the process. During fording, the air intake opening on the engine cover is closed, and air is instead drawn from the crew compartment, which is connected via a long tube to the water surface to allow air intake. Crews breathe through their own oxygen masks and are equipped with safety vests in case they need to swim to the surface.

As the practice was dangerous and seldomly used, the Yugoslavian Army issued an order in 1995 for all units to discard their fording kits. However, it appears that this order was not followed through.

Crew and Training

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M-84 tank crews consist of three: commander, gunner, and driver. The role of a loader was removed, thanks to the introduction of the autoloader. However, it can hardly be said that the introduction of the autoloader reduced the amount of necessary personnel required to operate the tank, since throughout its use, three crew members proved far too little for field maintenance and repair of the tank, and other tasks, such as keeping guard during rest. As such, spare tankers or other soldiers sometimes had to be attached to tank crews to keep their combat readiness at an acceptable level.

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The driver is considered to have the easiest job, as his main job is to drive the tank via a set of steering levers and pedals, which is said to be easier to operate than driving a car. The driver also has the most spacious compartment, with good legroom and pedals placed comfortably underneath the level of the seat, which is somewhat negated by his rather awkward sitting position, as he is forced to lean forward to took through the TNPO-168V periscope while operating the tank buttoned up. For night driving, a PPV-2 passive night periscope can be installed instead. The taller the driver is, the more the seat has to be reclined backwards, meaning the driver has to lean further forward, making this position particularly uncomfortable for tall crew members. Two TNPA-65 auxiliary periscopes facing towards the front-left and front-right are also available to the driver, positioned just above his primary sight. The front of the tank, in addition to the driver and his controls and instruments, houses the battery and fuel tanks.

Above the driver is a 50 mm thick escape hatch, through which the driver can poke his head out, allowing him to drive the tank in a more natural position at the expense of his safety. When this hatch is open, some features, such as turret rotation and smoke grenade launchers, are disabled so as to not hurt the driver. In addition to driving the tank, the driver is tasked with basic engine maintenance, and keeping track of fluids and additives required for its operation.

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M-84 - Tank Encyclopedia (77)

Driver training for tank operators in the former Yugoslavia lasted for less than three months and initially took place at the Zalužani training field in the Socialist Republic of Bosnia and Herzegovina. Following the breakup of Yugoslavia, the training for Serbia and Montenegro was relocated to the town of Vršac. While most candidates would typically possess a civilian driver’s license, it was not an official requirement.

The training curriculum began with small arms practice, followed by moto-technical theory classes, and practical experience in simulators. The hands-on training started with basic back and forth driving exercises within the tank, progressing to realistic driving scenarios. Regardless of weather conditions or seasons, training continued throughout the year, concluding with night driving exercises. Instructors, situated in the tank commander’s position, communicated with the drivers through intercom systems. Supervisors closely monitored and graded the trainees throughout the process.

Upon successful completion of the training, the new tank drivers were assigned to their units, where their education continued, particularly focusing on teamwork and understanding other roles within a tank. Conditioning training was a regular component, occurring at least once a month and intensifying every six months, when new gunners joined the unit.

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The gunner is positioned on the left side of the turret, with his primary responsibilities including operating the 125 mm main gun and PKT coaxial machine gun, along with the maintenance of all related parts. He has to be familiar with different modes of operation of the fire-control system, including the analogue mode of firing the main cannon, entirely without the FCS. The gunner is also tasked with loading the main gun in semi-automatic and manual mode, which is in practice a rare occurrence due to the reliable autoloader. In addition to his primary sight, the gunner has one TNP-165A periscope and another unknown periscope in his hatch, both facing forward-left at his disposal.

Despite having less space in the turret compared to other crew members, the gunner still enjoys more room than on the T-55 tank. His situation is helped by having his own roof hatch through which the gunner can get some fresh air or independently escape if anything goes wrong. Just behind his hatch, there is a rear-facing number light and a red positional light, which, when combined with two other lights above the rear mudguards, forms a triangle. The use of these lights is mandatory at night, allowing personnel behind the tank to estimate the direction in which the tank’s turret is pointed. Left and right positional lights can also be used as turn signals and brake lights.

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M-84 - Tank Encyclopedia (80)

Gunners embark on their practical training by engaging in live-fire exercises with the tank’s 7.62 mm coaxial machine gun. Initially, the PKT is fired from a stationary position, then from short stops and, finally, while the tank is on the move. The entire process is repeated during nighttime training. Upon successful completion of this training phase, gunners move on to the next stage on a larger training field. Here, they participate in the standard “tank platoon on the attack” drill using a specially modified M-84 tank equipped with a 12.7 mm heavy machine gun inside of its main cannon. Gunners are provided with limited ammunition and tasked with knocking down at least 70% of the presented targets. During this drill, targets appear suddenly, challenging the gunner’s perception skills. Some targets are set in motion, allowing the gunner to practice using the automatic lead function of the fire-control system. This feature, which automatically tracks the target upon its lasering, enables the gunner to aim for the center mass of a target without the need to compensate for its movement.

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Upon successful completion of this training course, gunners are dispatched to tank firing ranges, like the Pasuljanske livade training grounds in Serbia, where they get to practice with live 125 mm ammunition for the first time. It is a common experience among gunners, both veterans and newly trained, to feel unease and nervousness right before firing their first shell. This anxiety is so prevalent that some individuals resort to coping mechanisms, including illegal alcohol consumption. Those who fail the course may find themselves demoted and reassigned to less prestigious roles as IFV gunners in mechanized infantry units. However, as soon as the tank fires and the built-up tension releases, the initial anxiety dissipates, allowing gunners to proceed with their duties.

During the first day of live-fire training, targets are positioned at a distance of 2 km, and gunners engage them with APFSDS-T rounds from stationary tanks. Despite the perceived challenge, this exercise is generally considered straightforward, with the majority of gunners successfully hitting the target on their first attempt. The remainder of the day involves live firing with the Zastava M-87 anti-aircraft machine gun. Targets for it are placed on the ground at distances close to 1 km, and tracer ammunition is used in abundance, enabling gunners to quickly adjust their fire while practicing with telescopic and iron sights. This baptism of fire is followed up by a promotion of successful gunners to the rank of lance corporal (razvodnik) in the evening, creating a sense of euphoria within the camp.

On the following day, the tank platoon on the attack drill is repeated, this time with live ammunition. The drill kicks off with coaxial machine gun practice. Three or four tanks move down the course, each in its own parallel line. As the tanks advance, targets appear that must be engaged using the PKT machine gun. The entire crew actively participates in spotting these targets, with the tank commander typically guiding the gunner to acquire a target. If the gunner becomes disoriented or confused due to various factors such as anxiety, noise, heat, or smoke, the commander can turn the turret in the direction of his sight, assisting the gunner in target acquisition.

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Midway through the course, a stationary tank-sized target emerges at a distance of 1.5 to 2.5 km. The crew must engage this target with the main gun while the tank is in motion, and this task is generally completed with a high success rate, similar to the initial exercise. At the conclusion of the course, the crew exits the tanks and conducts small arms practice. The commander and driver use their M84 “Škorpion” machine pistols, while the gunner employs the Zastava M-70 AB2 assault rifle.

After completing this task, the crew returns to the tank and drives back to the starting position, where they receive a grade. However, any euphoria is immediately and deliberately cut short by the order to load the tanks onto flatbed railcars and tank transporters under strict discipline. This is done so that tank crews are instilled with the principle of not allowing themselves to relax or let their guard down after a successful combat mission. Upon returning to the unit’s barracks, tanks are refueled, and only then do the crews get some well-deserved rest. The subsequent days are dedicated to field maintenance and the cleaning of the main gun, ensuring the tanks are in optimal condition for future operations.

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If the tank crew is supposed to live and breathe as one, then the tank commander is the brain of such an organism. In addition to commanding the gunner and the driver, the commander is also tasked with target identification and designation and communication with other units on the battlefield. The commander observes the battlefield through his main DNKS-2 sight, two TNP-160 periscopes, and two TNPA-65 auxiliary periscopes embedded into his clam-shaped cupola. This configuration provides the commander with an impressive 288° field of view, with only a 72° dead zone to the rear.

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Rather than undergoing specialized training from the start, prospective tank commanders are selected from among sharp and high-performing gunners during their initial 6-month training. After completing the standard training, these chosen gunners undergo additional training specific to the commander role, attaining the rank of corporal (desetar). In contrast, tank drivers do not progress in rank and are never selected for commander training during peacetime.

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Nearly all JNA M-84 tanks were equipped with the RUT-1 (Radio Uređaj Tenkovski) radio set, which includes the PD-9 radio station, internal communications box, Šlemofons, AT-22 antenna stand, and the antenna itself. The Šlemofons contain noise-canceling headsets and a laryngophone, enabling the crew to communicate despite the very loud engine noise. In addition to the three crew members, there is also one Šlemofon mounted outside the tank, allowing infantry to communicate with the crew. Command variants and M-84AB export variants are equipped with multiple, foreign radio stations.

Yugoslavian Variants

T-72MJ Prototype Series

Five prototype T-72MJ tanks were produced by the end of 1983. Internally nicknamed ‘Mutants’ due to the nature of their construction, these were a mashup of delivered Soviet T-72Ms and domestic components. Though not assigned production numbers, they were given designations ranging from ‘001’ to ‘005’. Prototype series tanks were never intended to be issued to units. Instead, they were used for testing, overhaul training in repair facilities, and further research and development (R&D) work. Although three of these tanks were disassembled and rebuilt as training props for tank schools, at least one has escaped such a fate.

Tank ‘003’ was initially given to the Technical Testing Center (Tehnički Opitni Centar – TOC), where it stayed until passed onto the training battalion before ending up in the 3rd Brigade. Once the value of the tank as a prototype became recognized, the brigade gifted it to The Belgrade Military Museum. Currently, the tank is located in the warehouse in Kačarevo, together with other museum property not already displayed on the Kalemegdan fortress, including a Vihor tank prototype. This tank appears to be equipped with a DNNS-1 sight taken from one of the previously modernized T-55s from project Igman. The meteorological sensor on the folding carrier must have been added later, as such a design was not introduced until the tanks of the first series entered production.

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Furthermore, tank ‘005’ was given to the Military-Technical Institute (Vojnotehnički Institut – VTI) for R&D of new subsystems. Although its fate is uncertain, if it escaped scrapping, it is likely housed alongside ‘003’ in Kačarevo.

A distinctive feature of the tanks in the prototype series is the absence of smoke launchers at the front of the turret. This might be because the turrets were taken from the previously delivered T-72M tanks. T-72MJs also featured a short, non-collapsible carrying arm for the meteorological sensors, a trait shared only with the tanks of the zero series.

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Zero Series Tanks

The first real challenge for the Yugoslavian military industrial complex was the production of the zero series, comprising 10 M-84 tanks. Initially anticipated for completion by the end of 1984, this deadline was narrowly missed, and the tanks were finalized at the beginning of 1985. In contrast to the T-72MJ prototype series, these tanks were entirely constructed using domestic components.

The public debut of M-84 main battle tanks took place during the 1985 Victory Day parade on 9th May. Due to the limited availability, they were accompanied by freshly painted T-72M tanks, of which 65 had been procured for the 1st Guards Armored Regiment before M-84 production commenced.

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M-84 - Tank Encyclopedia (89)

The M-84s of the zero series were the first tanks to be assigned registration numbers, ranging from ‘21052’ to ‘21061’. In contrast to the T-72MJ tanks, M-84s of the zero series were equipped with smoke launchers at the front of the turret, and all featured rubber side skirts. They shared the short meteorological sensor carrier arm with a rubber damper with the T-72MJ prototype series, setting them apart from the remaining M-84 tanks.

Like the prototype series, these tanks were set aside for training and testing purposes. Initially, all of them were dispatched to the training centers near Banja Luka, specifically Manjača and Zalužani. On 24th February, 1989, tanks ‘21053’ and ‘21057’ were sent to the Technical-Repair Institute (Tehničko-Remontni Zavod – TRZ) in Hadžići for the overhaul training for M-84s. Some tanks from the zero series eventually underwent scrapping, repurposed as training props. Others remained in the SR Bosnia and Herzegovina, becoming a part of the 2nd Armored Brigade of the Army of Republika Srpska.

First Series

After the delivery of the zero series M-84s, an order was placed for the production of the first series, consisting of 55 tanks with some minor adjustments. This series saw the first batch of deliveries to the Yugoslav People’s Army, with the 252nd okbr. (Oklopna Brigada – Armored Brigade) in Kraljevo receiving the initial shipment of 47 tanks. The remaining 8 were allocated for different purposes.

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One tank from the initial series (registration number ‘21183’, chassis number ‘00006016D’, 16th produced in 1985), was assigned the designation ‘S1’ and dispatched to the USSR for testing in accordance with license requirements. The use of the M-84 designation for the Yugoslav tank had been a subject of significant dispute with the Soviets. However, the arrival and subsequent testing of this particular tank demonstrated sufficient differences from the licensed T-72M to warrant a designation change. Subsequent negotiations with the Soviets alleviated various restrictions, including those related to exports, ultimately allowing Yugoslavia to legally pursue sales abroad. Tank ‘S1’ was later returned to Yugoslavia, and another M-84 would be sent (according ot the Dr. Prof. Milorad Dragojević, sold) to the Soviets instead.

Additionally, two tanks from the first series, designated ‘L1’ (registration number ‘21177’) and ‘L2’ (number ‘21178’), were used for demonstrations to the potential Libyan buyers.

Another tank (registration number ‘21426’) was earmarked for conversion into an M-84K radio command tank.

Ultimately, all these first-series tanks that did not join the 252nd Armored Brigade, excluding one sent to Nikinci as an exhibition piece, found their way to the Banja Luka area for training purposes. Most first series tanks bear registration numbers between ‘21062’ and ‘21112’, but there are exceptions to this rule such as the ‘S1’ tank which received its registration number upon returning from the Soviet Union.

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In 1985, 14 tanks from the first series were delivered, with the remaining units supplied the following year. A distinctive feature of this series is the elongated, foldable carrier arm designed for the A20X (BL) meteorological sensor and two infrared radiation (IR) spotlights. The larger L-2AG IR spotlight is positioned to the right of the main cannon, while a smaller OU-3GK is mounted on the commander’s cupola, opposite the anti-aircraft machine gun. These spotlights were initially included to enhance the night-fighting capabilities of first series tanks, which were equipped only with passive night vision periscopes and sights. However, as the second production series of tanks introduced new second-generation night vision equipment, the spotlights were deemed redundant and were removed in subsequent series.

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Second, Third, and Fourth Series

The second series of M-84 tanks, delivered from 1986 onwards, introduced second-generation night vision equipment. This included the DNNS-2A gunner’s sight and DNKS-2 commander’s sight, enhancing the tank’s capabilities in low-light conditions. Additionally, the A10X (MB) meteorological sensors were utilized in the second series, replacing the more advanced A20X (MB) sensors which were present on previous M-84 tanks.

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The tanks produced in the second, third, and fourth series were virtually identical to each other, except for the M-84T subseries consisting of 40 tanks intended for Libya before the export deal fell through. The M-84T designation, where “T” stands for tropical, was informal rather than official. These tropical tanks were unique only in that the labels inside the tank were in English and their chassis numbers ended with a letter “T”. Following their completion, the M-84T tanks were not allocated to the JNA but were instead sent to Vrhnika, Slovenia, for storage as part of the war reserve.

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One tank from the second series (without a JNA registration number) was sent (possibly sold) to the Soviet Union for testing and remains on display at the Kubinka Tank Museum. Another one was modified by Yugoslav Army into an M-84K command tank variant.

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Before the deliveries of M-84AB tanks commenced, the first tanks sent to Kuwait were from the fourth series from the JNA stock, taken from the 211th Armored Brigade stationed in Niš. Either four or six of these tanks were dispatched to Kuwait for crew training while their variant of the tank was being produced and delivered. While they were not painted in desert camouflage like other Kuwaiti tanks, they might have been modified before delivery. One was pictured with two antennas, so it was likely equipped with the same Racal Dana radio stations as Kuwaiti M-84ABs. Unfortunately, these tanks found themselves in the midst of the Iraqi invasion and at least one was captured and later pressed into service by Iraq. One Iraqi M-84 appears to have been subsequently captured by the United States Army, and transported back to Texas.

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The initial 60 M-84 tanks of the second series were manufactured in 1986, following the completion of the 41 first series tanks. In 1987, the remaining 20 M-84s from the second series were produced, along with 40 M-84Ts. Production of the third series commenced the same year, delivering 60 tanks. In 1988, an additional 20 tanks of the third series were supplied, followed by 100 tanks of the fourth series. Once all fourth series tanks were delivered, the production transitioned to M-84As. In total, 300 tanks of the second, third, and fourth series were made.

M-84A

In accordance with the license, the Soviet Union was obligated to share developments related to the T-72M tank with Yugoslavia. When the new 60-105-50 composite armor from the T-72A was declassified and incorporated into the T-72M1, Yugoslavia obtained the new license, and work on updating the M-84 tank began. Alongside the new armor layout, a new V-46-TK 1000 hp engine and modified transmission were introduced. These modifications meant that the new tank would significantly differ from previous iterations of the M-84, warranting its classification as a separate variant. On 29th April, 1987, the General Staff ordered the designation of this new variant to be M-84A. This tank was both better protected and faster than its predecessor, being able to reach road speeds of up to 65 km/h.

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In 1988, an order was placed for the production of the first 30 M-84A tanks of the fifth series. Two M-84A tanks, designated as ‘P1’ and ‘P2’, were delivered ahead of the others and were dispatched for testing in Pakistan, which had expressed interest in acquiring these tanks. Although most of the M-84As were completed by 1991, issues with transmissions caused delays in their introduction into service. The JNA military commission refused to accept the finished tanks until all problems were resolved. Simultaneously, production of M-84AB tanks was underway, sidelining the M-84A until it became evident that conflict was brewing in Yugoslavia.

In early 1991, the situation flipped, and the JNA suddenly became eager to take over the approximately 60 finished M-84A tanks, while the Đuro Đaković factory began dragging its feet and delaying deliveries. Once the military authorities approved the tanks for delivery, the JNA took over most of the completed M-84As. In May 1991, a worker strike at the factory instigated by the HDZ (Hrvatska Demokratska Zajednica – Croatian Democratic Union) political party halted all further deliveries of finished M-84s. Thanks to these, 21 tanks, primarily M-84AB tanks from the sixth series, which the JNA also attempted to take over, were retained by the factory. How many M-84As the JNA managed to take for themselves is not known for certain, but the number seems to be in the range of 55 to 64.

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One notable difference between the M-84A and its previous variants is the arrangement of the external fuel tanks. The M-84A lacks the fourth fuel tank on the right side, and the fifth tank is reduced in size, resulting in M-84A tanks carrying 150 fewer liters of fuel, with a total capacity of 1,050 liters. In the space formerly occupied by the removed fuel tank, a new air filter has been installed on M-84A tanks.

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M-84 - Tank Encyclopedia (100)

M-84AB

Originally, the plan was to produce tanks for the Yugoslav People’s Army until the 1,000th tank was manufactured in 1995. Following this production run, the focus would have shifted towards the export market, with approval for extending the production run past 1,000 tanks already granted by the Soviet Union. However, the bankruptcy of SFR Yugoslavia and the increased interest in the M-84 from Kuwait led to a shift in priorities. Negotiations for the sale began in 1988, and a deal for the purchase of 200 tanks and 15 armored recovery vehicles (215 tanks according to some sources) was signed by the end of 1989. The contract was valued at half a billion USD, and to fund the production, Kuwait agreed to pay 30% of the contract price in advance. The contract also covered training, ammunition, spare parts, and maintenance of the tanks. Once the contract was fulfilled, new orders were expected to follow.

The Kuwaiti variant would be based on the newest M-84A, which was just entering production, and would be modified to meet specific Kuwaiti requirements. These variants would be designated M-84ABs, with sub-variants including the navigational M-84ABN and the command M-84ABK. The price at which Kuwait purchased M-84AB tanks was US$1,500,000 per unit.

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Compared to the M-84As, the M-84AB featured the following changes:

  • new tracks with removable rubber track pads
  • the addition of a searchlight to the right of the main cannon
  • two new radio stations, with an additional third one for command variant
  • new navigational equipment for the command and navigational variants
  • a modified DNNS-2A/6400 gunner’s sight, featuring a different reticle
  • new ballistics software, accounting for 6400 milliradians and expanded temperature range
  • an electric coolant level indicator
  • a case winder for phone on the back of the turret
  • translation to Arabic of all labels in the crew compartment
  • sand color camouflage paint
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Notably, there were no changes to air filters or the addition of air conditioning to enhance the tank’s operability in desert conditions. The M-84AB could be easily distinguished from other M-84 tanks by the combination of two ribs at the front, the 5+7 setup of smoke grenade launchers at the front, and the presence of a phone case winder at the back of the turret.

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Kuwaiti M-84AB and M-84ABK tanks were also utilized by the Croatian Army during the war against the Yugoslav People’s Army and the Serbian Army of Krajina. The exact number of tanks used and produced by Croatia remains unknown, but 15 of these commandeered tanks had to be recalled from the front and returned to Kuwait during the war. All other undelivered M-84AB tanks were kept by the newly created Croatian Army.

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M-84K and M-84AK

The command version of the M-84 tank, designated M-84K, was initially planned in 1988, with actual work commencing after the initiation of the M-84ABK command tank project for Kuwait. Two M-84 tanks are known to have been modified to the M-84K standard. The first tank, originally from the first series with registration number ‘21426’, was disassembled in Bosnia and Herzegovina in 1991. VTI (Military Technical Institute) engineers had been working on adapting the tank to the M-84K standard by replicating the disassembled T-72K tank, but the outbreak of the civil war in the republic halted their efforts. Vladimir Ivanović, an engineer who was previously heavily involved in the construction of the M-84 tank, had to put the M-84K back together using only the available parts.

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This particular tank featured the standard RUT-1 radio set, a PD-9 radio and a high-power radio set produced by Ei Niš, sourced from a captured Croatian T-55 command tank. Navigational equipment and an intercom system were taken from the command version of the BVP M-80 Vidra prototype, which was located in Rudi Čajavec at the time. Unfortunately, an extra generator, commonly present on command tanks, could not be added due to unavailability. Upon its completion, the tank was sent to a military unit and survived the war. It was later converted back to the standard M-84 configuration. This M-84K variant can be identified by the additional antenna mounted on the stowage box at the back of the turret. Unfortunately, no pictures of it appear to have survived to this day.

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M-84 - Tank Encyclopedia (107)

In 1994, the Federal Republic of Yugoslavia, consisting of Serbia and Montenegro, initiated the conversion of one M-84 and one M-84A (registration number ‘21458’) to the M-84K and M-84AK standards, respectively. These tanks were intended for use as armored brigade command vehicles, with the M-84K assigned to the 252nd Armored Brigade from Kraljevo and the M-84AK assigned to the 211th Armored Brigade from Niš. Unlike the M-84ABK command tanks for Kuwait, these tanks feature only two radio stations and two antennas, both located at generatorthe back of the turret. The specific radio stations used are not known, but they likely included one Racal Dana Jaguar V and one RU-20 or the domestic Pupin TRC 9310-3A. The tanks are equipped with a teleprinter, Teldix navigational equipment, and an auxiliary generator for producing power when the tank is not running.

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M-84 - Tank Encyclopedia (109)

Due to extra radio stations and other equipment taking up limited space in the crew compartment, command tanks feature less ammunition compared to the standard M-84 tank. In addition to two antennas, M-84K and M-84AK tanks can be recognized by the helmets their crews use. Instead of the domestic Šlemofons, which were incompatible with the new radio stations, crews of command tanks were issued with plastic helmets with microphones made by Racal. While these helmets did not provide ballistic protection, their purpose was to protect the crew inside the tank from injuries that could occur during movement. One improvement of these helmets compared to the standard Šlemofon is their better waterproofing. Regular Šlemofon is prone to soaking up water like a sponge, thus weighing itself down and causing discomfort for the wearer.

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Production Numbers

In total, including the 5 prototypes and 10 zero series tanks, a production run of 370 M-84 tanks was completed. Out of these, 358 were accounted for by the JNA, including the 40 M-84Ts. The remaining units were utilized for testing, research, and development, with one tank sent to the Soviet Union for evaluation, where it remained. The exact number of produced M-84A and M-84AB tanks is challenging to determine due to the circ*mstances surrounding their production. Most, if not all, of the 80 M-84A tanks from the fifth series were likely produced by spring 1991. The majority of these tanks were then taken over by the JNA, with a small number left in the Đuro Đaković factory. Any remaining M-84A tanks on the production lines were probably completed by Croatia during or immediately after the war. As for the M-84AB tanks, 149 were delivered to Kuwait before production priorities shifted for the Croatian Army’s needs. In total, it can be estimated that 599 M-84 tanks were produced for sure (assuming that all 80 M-84A tanks were completed), with approximately 50 or more tanks produced in the independent Republic of Croatia during and after the war.

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Table of production in SFR Yugoslavia

SeriesTank modelChassis numberRegistration number (JNA)Year of the delivery of last tankNumber of tanks produced
Prototype seriesT-72MJ//19845
Zero seriesM-84‘NUS 1’ – ‘NUS 10’‘21052’ – ‘21061’198510
First seriesM-84‘006001’ – ‘006055’‘21062’ – ‘21112’198655
Second seriesM-84‘007001D’ – ‘007080D’‘21113’ – ‘21239’198780
Second series (Tropical)M-84 (M-84T)‘007001T’ – ‘007040T’‘21113’ – ‘21239’198740
Third seriesM-84‘061001’ – ‘061070’‘21240’ – ‘21314’198870
Third seriesM-84‘060001’ – ‘060010’‘21240’ – ‘21314’198810
Fourth seriesM-84‘059001’ – ‘059040’‘21315’ – ‘21418?’198840
Fourth seriesM-84‘062001’ – ‘062030’‘21315’ – ‘21418?’198830
Fourth seriesM-84‘097001’ – ‘097030’‘21315’ – ‘21418?’198830
Fifth seriesM-84A‘150001’ – ‘150080’‘21418?’ – ‘21481’199180 ordered
all delivered?
Sixt series (Kuwait)M-84AB‘160001’ – ?/1991200 ordered,
149 delivered
Total599

Tank assembly typically took around two months, assuming all required parts were available, although this was not always the case. As part of the production process, every hundred tanks included one produced empty hull specifically for armor testing purposes. The component hampering the production pace the most was the aiming devices, with 60% of the materials for it needing to be imported, resulting in slow and uneven deliveries.

During the transition from M-84 to M-84A tanks, something went wrong at the FAMOS factory, and the reliability of transmissions plummeted. It was later discovered that the main culprit causing these issues was the transmission oil used. To address this, the 14th Oktobar factory was introduced as a parallel transmission producer. However, this too led to quality problems with the delivered modules, as the new facility was mastering the production process. Despite these challenges, the Đuro Đaković factory managed to achieve the assembly of 120 tanks per year, with peak production reaching as high as 150 tanks.

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After March 1991, production was characterized by growing mistrust among cooperative partners. In one of the final orders from the Đuro Đaković factory to Rudi Čajavec, they requested an additional delivery of 20 RUT-1 sets and 100 Šlemofons. Commercialist Đoko Kaluđerović who received the order expressed disbelief, exclaiming, “What do they think we are, stupid?”, before tearing up the order and throwing it into trash.

The parts for the fifth batch of M-84AB tanks were delivered in May 1991. However, after the Federal Secretariat for National Defense (Savezni Sekretarijat za Narodnu Odbranu – SSNO) lost control of the Đuro Đaković factory, the delivery of all parts ceased on 6th May, 1991. Despite this, work on the tanks continued at a slower pace, now for the needs of the new Croatian Army. Parts were sourced from previously delivered stocks, cannibalization of destroyed vehicles, and from abroad, as many parts of the T-72M and T-72M1 tanks were compatible with the M-84s.

May 1991 also marked the final batch of tanks delivered to the JNA, as the 211th Armored Brigade was compensated for the loss of their tanks to Kuwait with the delivery of six new M-84As.

To prevent the lucrative contract from falling through, Yugoslavia explored various options to continue the production of M-84 tanks independently. Discussions relating to this were held in winter 1991 at a resort in Kruševac, attended by representatives from many companies involved in tank production and a delegation from the Đuro Đaković factory. According to the created study, the republics of Serbia and Montenegro were already producing parts covering approximately 23.70% of the monetary value of the tank, and an additional 10% of parts could be put in production with relative ease. Another 14,67% was expected from companies in the Republika Srpska, and the remaining value was to be covered by foreign imports.

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Although this plan was set in motion and the 14th Oktobar plant was prepared to start production, the conflict in Bosnia severed crucial ties with important suppliers such as Rudi Čajavec, undermining the feasibility of the idea. Unwilling to abandon the project, the leadership of the 14th Oktobar plant decided in April 1992 to shift towards the production of M-84AI recovery vehicles, 15 of which had been previously ordered by Kuwait.

M-84AI

Even before the outbreak of the conflict, collaborative efforts with Poland were underway to develop an armored recovery vehicle (ARV) variant based on the M-84AB, akin to their WZT-3. By 1992, substantial progress had already been made through prior cooperation between the Đuro Đaković factory and Polish suppliers. A delegation from the 14th Oktobar factory successfully negotiated to obtain copies of the related documentation and redirect deliveries of purchased knock-down kits to their facility. While the Poles supplied the casemates, 14th Oktobar took on the responsibility of producing the chassis for installation. Due to time constraints, these chassis were assembled from predominantly imported parts, obtained through less conventional means, despite the arms embargo against FR Yugoslavia. This allowed production to commence, and an order for a test batch of 5 M-84AI tanks was placed to evaluate the new production line. The first ARV was completed by August 1992, with the rest of the batch following soon after. Regrettably, the M-84AIs could not be exported to Kuwait due to the embargo, leading to their incorporation into the Yugoslavian Army instead. In total, 5 M-84AIs were manufactured by the 14th Oktobar factory, with the possibility of the Đuro Đaković factory having one prototype as well.

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M-84 - Tank Encyclopedia (115)

Service during the Yugoslav Wars

Anticipating political instability and facing a decreasing number of new recruits, the Yugoslav People’s Army initiated a substantial reorganization program in 1988 known as Plan Jedinstvo (Unity). The program aimed to overhaul the chain of command to mitigate the influence of political factors on army leadership, enhance the hom*ogeneity of the army, and curb the growing influence of territorial defense units. Three military area commands were set up to replace the six army commands, whose areas of jurisdiction previously overlapped with the borders of republics. The plan also called for the disbandment of all divisions, to be replaced by new corps-size units comprising armored, mechanized, or motorized brigades. The praetorian 1st Guards Proletarian Mechanized Division in Belgrade was the sole exception to this reorganization. While the Jedinstvo Plan was completed by the end of 1989, a revised plan, Jedinstvo 2, was introduced in February 1990, followed by Jedinstvo 3 in July of the same year. These urgent reorganizations initiated a process of demilitarization in politically sensitive regions, transitioning motorized brigades stationed there to reserve status until their conversion to mechanized brigades. The rationale behind this move was the perceived elimination of the threat to these regions following the collapse of the Warsaw Pact. However, this decision had a dual impact. The demobilization of units in future conflict zones left the Yugoslav People’s Army without the necessary infrastructure, local support, and reserves essential for conducting operations in these areas. Consequently, power vacuums in these regions were filled by territorial defense units, militias, and police forces loyal to the leaders of individual republics and secessionist regions rather than the centralized authority of the Army.

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Once the reforms were complete, the disposition of M-84 tanks in the units of the JNA was as follows:

  • 1st Armored Brigade (14th Corps) – Vrhnika, SR Slovenija – half a brigade worth of M-84 tanks (left to VRS)
  • 4th Armored Brigade (10th Corps) – Jastrebarsko, SR Croatia – one battalion worth (left to RKS)
  • 211st Armored Brigade (21st Corps) – Niš, SR Serbia, with one battalion stationed in Leskovac – included large amounts of M-84As
  • 243rd Armored Brigade (41st Corps) – Skoplje, SR Macedonia – one battalion worth
  • 252nd Armored Brigade (37th Corps) – Kraljevo, SR Serbia – equipped with the first series tanks
  • 329th Armored Brigade (5th Corps) – Banja Luka, SR Bosnia and Herzegovina – half an armored brigade
  • 51st Motorised Brigade (24th Corps) – Pančevo, SR Serbia – one battalion worth (left to RKS)
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Additional M-84 tanks were stationed at:

  • Pivka (SR Slovenia) – training field for Vrhnika VP (Vojno Podrucje – Military Area) 5312
  • Slunj (SR Croatia) – training field for Jastrebarsko VP 2465
  • Kindrovo (SR Croatia) – Đura Đaković factory proving grounds
  • Pasuljanske livade (SR Serbia) – training field for the Serbian military areas, including Kraljevo VP 8977, Niš VP 6592, and Belgrade VP 1552
  • Nikinci (SR Serbia) – single exhibited first series tank.
  • Međa (SR Serbia) – training field for Kraljevo VP 8977
  • Deliblatska Peščara (SR Serbia) – training field for the 51st Motorised Brigade from Pančevo
  • Orešac (SR Serbia) – training field for military schools and academies
  • Kalinovik (SR Bosnia and Herzegovina) – proving ground for the APFSDS-T ammunition
  • Manjača (SR Bosnia and Herzegovina) – training field for the M-84 gunners
  • Krivolak (SR Macedonia) – training field for Skopje (VP 4466)

Seemingly turning a blind eye to the deplorable economic situation in the country, the JNA envisioned an ambitious expansion of the mechanized fleet, with most infantry trucks and all M-60 APCs being replaced by the new M-80A IFVs by 2005. Additionally, the plan outlined the replacement of T-34/85 tanks with M-84As by the end of 1995, followed by the start of the production of the new Vihor MBT at a rate of 100 tanks per year until 2010, by which point all T-55 tanks would have been replaced. The modernization of M-84 tanks was also planned, incorporating components developed for the Vihor tank, such as explosive reactive armor and an updated fire-control system with integrated thermovision. However, all such plans came to a halt due to the harsh reality of civil wars and the subsequent collapse of the country.

The political situation in the late 1980s and early 1990s was marked by deteriorating relations between the Slovenian and Croatian republics, seeking greater autonomy and a reorganization of the state into a loose federation, and the Republic of Serbia-dominated bloc resisting these changes. Hopes for a resolution to the political turmoil at the 14th Congress in January 1990 were dashed when the Slovenian delegation walked out after their reform proposals were not approved. The Croatian delegation, unwilling to continue without the Slovenian delegation, also walked out, effectively signaling the end of the unified Communist Party. In 1990, the first multi-party elections were held in the Yugoslav republics, with anti-communist and nationalist parties beating communist parties in all republics except Serbia, Macedonia, and Montenegro.

Given the JNA’s prior takeover of weapon depots in sensitive regions, the leadership in Croatia and Slovenia began importing arms from Eastern Europe to strengthen their ministries of interior and territorial defense units, creating loyal militias as precursors to republican armies. Facing persecution from the new nationalist government and opposing Croatia’s secession from SFR Yugoslavia, ethnic Serbs in Croatia petitioned for changes and greater cultural autonomy. When these petitions were denied, Serbs in Croatia organized a referendum on the creation of an autonomous Union of Municipalities of Northern Dalmatia and Lika, a precursor to the independent Republic of Serbian Krajina. The Republic of Croatia vowed to stop the referendum by any means necessary, leading to the Balvan (Log) Revolution. Blockades were erected on major roads leading to Serbian ethnic areas in southern Croatia to prevent Croatian Ministry of Interior troops from canceling the referendum. The Union of Municipalities of Northern Dalmatia and Lika was soon joined by other majority-Serbian municipalities, leading to its name change in December 1990 to Srpska Autonomna Oblast (Serbian Autonomous Region – SAO) Krajina. This entity began establishing its own police and territorial defense units, leading to clashes with Croatian forces along the entire contact line. On the 19th January, 1991, the JNA was ordered to disband the two quasi-armies on Croatian territory. However, this order could not be carried out. In March, the army leadership sought approval from the presidency to declare a state of martial law. This request was denied, and in response, the army’s leadership publicly expressed their frustration, stating that they were handicapped and unable to prevent ongoing weapon smuggling. To discourage further escalations between conflicting sides, the Yugoslav People’s Army was authorized to deploy units in Croatia to create buffer zones between the conflicted sides, drawing from a strategy previously successfully employed in Kosovo in 1989. These deployments marked the first combat use of the M-84 tanks, as JNA units occasionally came under fire from opposing forces.

Slovenian Territorial Defense and the Ten Day War

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Although the conflict in Croatia seemed on the brink of erupting into a full-scale war, the first hot war was the one between Slovenian Territorial Defense forces and the Yugoslav People’s Army. On the 25th June, 1991, both the republics of Croatia and Slovenia declared de facto independence from the Socialist Federal Republic of Yugoslavia. On the same day, the Federal Council of the Assembly of SFRY dismissed these declarations as unconstitutional, instructing the JNA to take control of all border crossings in the Republic of Slovenia. While the JNA anticipated Slovenia’s declaration of independence, there was internal debate on the appropriate course of action to bring the republic back into alignment.

Colonel-General Blagoje Adžić, the Chief of Staff of the JNA, advocated for a large-scale invasion to depose the secessionist Slovenian government. However, General of the Army Veljko Kadijević, the Yugoslav Defence Minister, argued for a more cautious approach, hoping that a show of force would be sufficient to dissuade the Slovenian government from pursuing independence with minimal casualties. Ultimately, Veljko Kadijević’s approach prevailed, and a limited military operation commenced the following day.

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M-84 - Tank Encyclopedia (120)

The task of recapturing border crossings fell to the 5th Military District and its subordinated units, including the 14th and 31st Corps stationed in Slovenia, supported by JNA units in Croatia. The 5th Military District comprised around 40,000 officers and soldiers, with a substantial artillery presence and the backing of the Yugoslav Air Force. According to a 1989 report, the district had 752 tanks at its disposal, including 96 T-34/85s, 520 T-55s, 15 PT-76s, and 121 M-84s. The majority of the M-84s belonged to the 1st Armored Brigade in Vrhnika, Slovenia (64 at full strength). The remainder consisted of a single M-84 battalion (21 tanks at full strength) from the 4th Armored Brigade in Jastrebarsko, Croatia, supplemented by a war reserve of 40 M-84 tanks stationed in Vrhnika, originally produced for Libya.

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Despite this apparent superiority on paper, the JNA was crippled by low deployment numbers, a peacetime mindset among its soldiers, desertions, and poor morale. As a multiethnic force, the JNA suffered from internal divisions, as Slovenians serving in the JNA especially refused to fight their fellow countrymen, with Croatians, Albanians, and to a lesser extent Bosniaks and Macedonians showing similar reluctance to combat Slovenians they had no animosity towards. Similar insubordination existed throughout the entire chain of command, extending up to the highest levels of authority.

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On the opposing side were approximately 35,000 mobilized personnel from the Slovenian territorial defense and police. Although lacking the firepower of the JNA, these well-motivated mobile units, armed with light anti-tank weapons and trained for asymmetrical warfare, would prove to be a formidable challenge, delivering a harsh reality check to the JNA and punishing it for its apathetic approach to warfare.

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The war commenced on 26th June, 1991, when JNA vehicles from Slovenia and Croatia began leaving their barracks to seize control of border crossings and other strategically vital locations. At first, Slovenian units offered no resistance, as both sides adhered to the principle of not firing first. The only form of opposition encountered by the JNA were civilian roadblocks, which were bypassed with minimal effort. By the following day, most JNA units reached their objectives, even as Slovenian forces began harassing targets of opportunity. On 28th June, Slovenian forces launched a general counter-offensive against JNA positions, persisting until the war’s conclusion. Exposed JNA units guarding border crossings and garrisons in Slovenia that remained loyal to the federal government found themselves effectively besieged by Slovenian forces. These units were cut off from supplies and reinforcements, with relieving JNA columns halted by roadblocks and subsequently attacked by small anti-tank teams, often resulting in their surrender to Slovenian forces. Upon surrender, weapons from these garrisons or columns were distributed to Slovenian Territorial Defense units, further bolstering their capabilities. This kind of maneuver warfare with sporadic fighting had JNA leadership puzzled, as they could not devise an effective counter-strategy without escalating the war. Slovenia also outmaneuvered Yugoslavia in the geopolitical arena, employing a well-planned media campaign that garnered international support and pressured Yugoslavia to end the war.

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Despite Chief of Staff General Blagoje Adžić’s fervent lobbying for unleashing the JNA’s full might and resorting to the backup plan of a large-scale invasion, his proposals were once again rebuffed by Yugoslav leadership. At this point, the top was willing to let the ethnically hom*ogeneous Slovenia leave the federation without strings attached. The low-intensity conflict eventually subsided, marked by a ceasefire signed on the 3rd July and the Brioni Agreement, which deferred Slovenian and Croatian independence for an additional three months. In exchange, the JNA had to completely withdraw from Slovenia, and the Slovenian Territorial Defense assumed its responsibilities of defending the Republic. The evacuation of the JNA commenced soon after the agreement was signed, with RV & PVO (Ratno vazduhoplovstvo i protivvazdušna odbrana – Air Force and Anti-Aircraft Defence) units being the first to leave, followed by the 31st Corps and then the 14th Corps. Evacuating heavy equipment, including tanks, proved challenging due to sabotage from within the JNA ranks. Disloyal officers and tank crews deliberately disabled tanks to prevent them from leaving Slovenia. Batteries were damaged and drained to immobilize the tanks and prevent their loading onto trains. At Vrhnika, one Slovenian officer even took a pickaxe to the DNNS-2 aiming sights of M-84 tanks, and one M-84 is said to have been filled with concrete from a cement mixer. Evacuating the equipment through the Republic of Croatia posed significant risks, as the Croatian National Guard and other militias would occasionally try to intercept and plunder these trains. As the conflict in Croatia intensified and transformed into a full-fledged war, further evacuation of JNA equipment became impossible, as the land route to Yugoslavia was cut off. Consequently, the JNA left the remaining heavy equipment of the 14th Corps in Slovenia and evacuated its personnel via air and sea.

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M-84 - Tank Encyclopedia (126)

Casualties on both sides remained remarkably low due to the sporadic nature of combat in Slovenia, with fewer than 70 fatalities and 350 individuals sustaining injuries. Approximately 5,000 JNA soldiers either deserted, surrendered, or were captured during the course of the conflict. According to Konrad Kolšek, six M-84 tanks were lost during the Ten-Day War. The first tank was lost on 27th June, near the town of Meste after suffering a breakdown and being abandoned by the 1st Armored Brigade. Upon discovery by Slovenian members of the territorial defense, the tank was blown up. The Brigade experienced a further two losses and two damaged tanks before the end of the war. The 4th Armored Brigade, arriving from Croatia, similarly had a streak of bad luck. Initially, a column of their M-60 armored transporters was encircled by the Slovenian Territorial Defense. The relief force, comprising an armored company and a mechanized company, was halted by Territorial Defense units and accidentally bombed by the Yugoslav Air Force, resulting in one destroyed M-84 and three others damaged.

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After the conclusion of hostilities, Slovenia found itself in possession of at least 57 M-84 tanks, comprising those captured during the war, sabotaged tanks, tanks of the 1st Armored Brigade left behind by the JNA, and a number of M-84Ts from the war reserve which could not be fully evacuated in time. Two batches of 27 M-84 tanks were assigned to the newly formed 54th and 24th armored-mechanized battalions, while another 4 tanks were allocated to a training unit.

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Croatian Army and the Civil War in Croatia

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The Brioni Agreement did little to ease tensions in the Republic of Croatia. Following the establishment of SAO Krajina, two additional autonomous regions, SAO Western Slavonija and SAO Eastern Slavonija, Baranja, and Western Syrmia, were formed by Croatian Serbs with the tacit support of the JNA. Concurrently, the Croatian forces launched a series of attacks on JNA bases, collectively known as the Battle of the Barracks. By this stage, Croatian troops, much like their Slovenian counterparts during the Ten-Day War, primarily relied on light infantry. This force was composed of territorial defense units, police forces, the Croatian Defence Forces paramilitary organization, and the newly established Croatian National Guard (Zbog Narodne Garde – ZNG), initially part of the Ministry of Interior before being later renamed into the Croatian Army (Hrvatska Vojska – HV).

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No M-84 tanks appear to have been captured during the Battle for the Barracks, as the sole JNA unit in Croatia equipped with M-84 tanks, a battalion from the 4th Armored Brigade, was stationed in Serbian autonomous regions and later integrated into the Serbian Army of Krajina. Instead, Croatian forces primarily acquired M-84 tanks from the Đuro Đaković factory, supplemented by a smaller number captured on the battlefield during the conflict. As tanks coming from the factory were predominantly M-84A and M-84AB models, Croatia possessed qualitatively the best M-84 tank park throughout the war, rendering the first to fourth series M-84 tanks in the Croatian Army somewhat rare. Two of those tanks were captured from the JNA’s Technical Military Academy in Črnomerec, Zagreb, thanks to Captain Zoran Tintor, who disabled their engines, preventing their evacuation when the JNA withdrew from the city. Furthermore, during the Battle for Vukovar, Croatian troops seized a first series M-84 from the 252nd Armored Brigade.

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The exact number of tanks acquired by the Croatian National Guard from the Đuro Đaković factory remains unclear. Many sources indicate that a worker strike on 5th of May, 1991, prevented the JNA from taking control of 21 finished tanks, including at least 7 M-84As from the fifth series. On 17th September, 1991, these M-84A tanks, along with three M-84AB tanks completed for Kuwait, were handed over to the Ministry of Defence of the Republic of Croatia. Subsequently, all M-84A tanks were seemingly allocated to the 109th Brigade along with eight tank crews. In September 1991, the 108th Brigade was established and equipped with M-84AB tanks. On 24th September, 1991, this brigade had at its disposal 10 M-84AB tanks, one M-84ABK command tank, and 12 tank crews. Another M-84A tank, nicknamed “Crni Leptir” (Black Butterfly), was delivered to the 1st Mechanized Guard Brigade from the Đuro Đaković factory. Later, the Brigade seems to have been reinforced with two more M-84ABs and one M-84ABK. Throughout the conflict, other units of the HV would receive M-84 tanks as well.

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M-84 - Tank Encyclopedia (133)

Đuro Đaković was likely able to complete whatever tanks were left on the assembly line in 1991, after which the focus of the factory was shifted to repairing damaged and captured tanks. In November 1991, three such tanks were present in the factory. The reduced work pace led to factory workers being sent to the front as mechanics and tank crews. The first recorded use of an M-84 tank by Croatian forces occurred during the attack on the Gromačnik military depot on 15th September, 1991. Although the depot was successfully captured, it was nearly empty, disappointing the Croatian forces.

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The Croatian M-84 tank force faced a maintenance challenge in 1992, experiencing a shortage of ammunition and spare parts. The only available method to obtain new spare parts was through the cannibalization of other tanks. Complicating matters further, Croatia was operating tanks that belonged to Kuwait. On the orders of Franjo Tuđman, the President of Croatia, on the 15th February, 1992, 15 Kuwaiti tanks, including those from the 108th Brigade, were taken from the Croatian Army and sent to the Đuro Đaković factory for refurbishment. Demonstrating that business and money have no allegiance, the tanks were sent to Bar Harbor in the Republic of Montenegro in April 1992 and handed over to the Yugoslavian company Yugoimport, responsible for their export. Before the tanks could be shipped to Kuwait, a two-man military commission consisting of Srđan Radovanović and Vladimir Ivanović conducted a thorough examination to ensure they were in factory condition. As the Đuro Đaković factory, the finalizer of the tanks, was obligated to rectify any issues, the commission was especially thorough, demanding the complete replacement of any parts showing the slightest signs of use and wear. Among other parts, five main guns had to be replaced with new ones because their increased diameter indicated prior combat use. Even a plaque on the training mock-up, reading “ĐĐ Slavonski Brod Jugoslavija”, had to be replaced, as someone had scratched off “Jugoslavija” (Yugoslavia) from it. Begrudging workers had to travel back to the Đuro Đaković factory just to bring a new plaque.

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Once all the tanks were refurbished to factory condition, the commission granted an export license, and the tanks were sent to Kuwait. Through connections and backroom deals by the secret service, the truck transporting all the removed parts from the exported M-84AB tanks ended up in Republika Srpska instead of returning to the Đuro Đaković factory. These parts, although previously used, were still in good condition and were utilized for refurbishing the tank force in Republika Srpska until the end of the war. In return, the Republic of Croatia successfully obtained much-needed funds to pay workers at the Đuro Đaković factory, along with shipments of ammunition and spare parts from Kuwait. This not only helped address some of the maintenance issues but might have even allowed Croatia to resume tank production at the Đuro Đaković factory during the war.

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In February 1992, the Republic of Croatia achieved international recognition. This was followed up by the replacement of JNA peacekeepers (who were, at this point, trying to keep pieces of Croatia rather than peace) with the United Nations Protection Force, which drastically reduced the intensity of the fighting. The conflict then evolved into Croatian forces launching a couple of major operations each year, gradually exerting pressure on the Republic of Serbian Krajina until the decisive Bljesak (Flash) and Oluja (Storm) operations brought it to a definitive end.

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These operations also resulted in the Croatian Army acquiring additional M-84 tanks, as those of the Serbian Army of Krajina that were not destroyed or evacuated ended up in Croatian possession. Some M-84 tanks of the Serbian Army of Krajina are known to have been captured near Petrova Gora. The total number of tanks captured on the battlefield is unknown, but it was probably around a couple dozen. Considering that the Croatian Army currently owns 75 tanks, the remaining tanks were delivered by the Đuro Đaković factory. The exact number of tanks delivered throughout and after the conflict is unknown, though tank production and modernization work seemed to have continued until 2003, when the last two M-84A4 tanks were delivered. Additionally, three T-72M tanks were captured by Croatian forces during operations in 1995, and along with other M-84 tanks. These tanks were converted to the M-84A4 standard in 1996 and 1997.

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JNA in Yugoslav Wars

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After the conflict in Slovenia, it became increasingly evident that the original goal of the JNA to preserve the unity and integrity of Yugoslavia would not be achieved. Consequently, the JNA, which was given more leeway in handling the conflict in Croatia, began to throw its support behind the local Serbs. During this time, the JNA began transitioning from a multiethnic force to a predominantly Serb army, exacerbating its manpower issues, as conscripts could now only be drawn from Serbia and Montenegro, where general mobilization was never carried out. Reservists called up for service were often poorly trained and motivated. Despite this, they were entrusted with expensive equipment, such as M-84 tanks, leading to these becoming inoperable due to inappropriate use and maintenance. The leadership of the army also suffered, as non-Serbian officers deserted, and the remaining corps exhibited slow and reactive decision-making. Overall, the army was in a state of disintegration when the Battle of the Barracks began.

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M-84 - Tank Encyclopedia (141)

In response to Croatian attacks, the Yugoslav People’s Army escalated its involvement by planning a campaign aimed at disarming the Croatian Military, removing its leadership from power and unblocking besieged JNA barracks in conjunction with local Serb forces. The operation began on the 3rd October, 1991 along the entire border. One effort aimed at relieving besieged barracks near the town of Vukovar escalated into the biggest battle of this short stage of a war – the Battle for Vukovar. This protracted engagement unfolded in multiple phases, with the town subjected to regular artillery fire and gradual encirclement. As the JNA refused to bypass the town, the entire offensive in eastern Slavonija got bogged down by the fighting around Vukovar.

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Despite being the trump cards of the JNA, the M-84 tanks found themselves out of their depth. Rampant and irregular minefields laid by Croatian defenders could not be cleared due to a lack of engineers, confining the tanks to roads. Infantry support often was not available due to failed mobilization and the disintegration of JNA units. When infantry was available, it would demand that the tanks lead the way, often leaving them to battle the enemy on their own. A particularly poignant moment occurred during ambushes on Trpinjska Street near Borovo Naselje, where the JNA suffered considerable losses, including 4 M-84 tanks, 1 T-55 tank, 3 BVP-80 armored fighting vehicles, and an armored recovery vehicle, all succumbing to attacks from light handheld anti-tank launchers. At the time of the ambush, JNA infantry was being held back by mortar and sniper fire. Deficiencies in infantry support forced the tank crews to compensate with sheer firepower, allowing themselves liberal rules of engagement and reliance on artillery support.

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After the reorganization in the JNA chain of command in the second half of September, the situation began to improve, as trained engineers and well-motivated volunteer paramilitaries from Serbia started substituting JNA infantry in tank support roles. Thanks to these reforms, JNA and territorial defense forces started making steady gains around the town once again in early October. The Battle of Vukovar saw one of the rare tank-on-tank confrontations of the Yugoslav Wars, when on 13th October, 1991, T-55 tanks and possibly one M-84 of the Croatian 109th Brigade sought to relieve Vukovar but instead ran into entrenched M-84 tanks of the 252nd Armored Brigade from Kraljevo. After losing half a dozen tanks, the 109th Brigade was compelled to retreat, and the town surrendered soon after.

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The Battle of Vukovar thoroughly exhausted the Yugoslav People’s Army, and the attempt to continue the offensive afterwards quickly ran out of steam. In November 1991, the Croatian Army attempted a counter-attack, erasing some of the JNA’s gains. However, by the end of the year, both sides were spent and locked in a stalemate. This pattern was replicated throughout the entire front, with the JNA’s offensive initially making gains before becoming bogged down and checked by Croatian counter-attacks. One of the last military operations in 1991 was a Croatian offensive named Vihor (Whirlwind). During this operation, the Croatian 102nd Infantry Brigade managed to establish a brief bridgehead across the River Kupa near the town of Glina. However, a platoon of M-84 tanks, coincidentally moving through the area at that time, played a crucial role in halting the attack, forcing the 102nd Brigade to retreat back across the river without much of its heavy equipment, including 8 tanks, 2 APCs, and 7 boats.

Republic of Serbian Krajina

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On 26th February, 1992, the self-proclaimed autonomous regions SAO Krajina, SAO Western Slavonija, and SAO Eastern Slavonija, Baranja, and Western Syrmia united to form the de facto independent Republic of Serbian Krajina. Despite controlling close to one-third of the territory of the Republic of Croatia, totaling about 17,000 km2 at its peak, the new state only had one-tenth of its population. As such, the Republic of Serbian Krajina heavily relied on subsidies from the JNA and volunteer formations recruited from Yugoslavia. Krajina’s geopolitical situation was also unenviable. It had only two allies, the Republika Srpska and the reorganized Federal Republic of Yugoslavia. Apart from the western exclave, most of the Republic of Serbian Krajina’s territory was isolated from the Yugoslavian mainland. Its supply lines passed through Republika Srpska, which, also fighting for its life, was more than willing to tap into the supplies intended for its weaker ally to enhance its own chances of survival. The situation worsened when the JNA peacekeepers left the Republic of Serbian Krajina around the time of its founding, leaving it to fend for itself against the increasingly formidable Croatian Army.

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To increase its chances of survival, local territorial defense units, special police brigades, and disbanded units of the Yugoslav People’s Army were reorganized into the Serbian Army of Krajina (Srpska Vojska Krajine – SVK), officially established on the 17th October, 1992. This army was structured into six under-strength corps, comprising 26 brigades and 5 independent regiments. Fielded manpower estimates range from 35,000 to 55,000 personnel, falling short of the goal of 80,000 due to mobilization challenges. Heavy equipment for this Army was previously provided by the JNA, which deliberately left some of its weapons during its retreat out of Croatia. According to the Krajina Territorial Defence High Command, soon after its formation, the SVK was equipped with 262 tanks, 56 BTRs and BVPs, 1,360 artillery pieces of all calibers, 2,574 transports and utility vehicles, and even a tiny air force of about 30 planes and helicopters. Among the equipment were 31 M-84 tanks, left behind by the 622nd Motorized (51st Motorized) and 4th Armored Brigades of the JNA.

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M-84 - Tank Encyclopedia (149)

Despite stocks of heavy equipment later boosted by additional deliveries from Yugoslavia putting its level of mechanization on a near-peer level with the Croatian Army, the Serbian Army of Krajina struggled to reform effectively from its origins as a territorial defense force. It remained characterized by immobility, supply shortages, poor training, and lack of discipline and motivation. This was reflected in its use of tanks, which were evenly distributed along the front as static artillery pieces for infantry fire support, with few attempts to concentrate them into more mobile formations or use them as reserves. In 1995, all M-84 tanks would be grouped in the 2nd Armored Brigade of the Corps of Special Units, one of the few reserve formations ever created in the Republic of Serbian Krajina. The wide front with little strategic depth and the poor state of the army eventually led to the Serbian Army of Krajina’s defeat in 1995. Surviving M-84 tanks retreated into Republika Srpska, where they were interned. At least five M-84 tanks were destroyed by the 2nd Armored Regiment to prevent them from falling into Croatian hands intact.

Republika Srpska

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Amidst the War in Croatia, another conflict was brewing in the Republic of Bosnia and Herzegovina, which will come to be characterized as the most vicious war on the territory of the former Yugoslavia.

While there was no one single trigger for this conflict, the violence began escalating with the 1992 independence referendum, where Bosnian Serbs boycotted the vote, while Bosniaks and Bosnian Croatians voted in favor. By April of 1992, the Republic of Bosnia and Herzegovina was a three-way battleground among its three constituent peoples, with a brief intervention from the JNA and the Croatian Army also becoming involved in the chaos.

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Anticipating the need to withdraw from Bosnia and Herzegovina, similar to its withdrawal from Croatia after it achieved international recognition, the JNA played a key role in creating the Army of the Serbian Republic of Bosnia and Herzegovina, soon after renamed to Army of Republika Srpska (Vojska Republike Srpske – VRS). The army was established on 12th May, 1992, incorporating dismissed JNA units, consisting exclusively of Bosnian Serbs, along with territorial defense forces and other political militias. Once again, heavy equipment, including M-84 tanks from the remaining 1st Armored Brigade, which had only partially evacuated from Slovenia, was left behind by the JNA during its retreat to the remaining Yugoslav territory. These tanks would later be merged with the remnants of JNA’s 329th Armored Brigade to form the 1st Armored Brigade of the Republika Srpska, the largest armored unit in Bosnia and Herzegovina. This unit played a crucial role in Operation Corridor 92, the largest and arguably most successful operation devised by the Army of Republika Srpska, soon after its establishment.

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Operation Corridor 92 marked the first instance in the Yugoslav Wars where tanks were employed in accordance with their military doctrine, enjoying robust support from other branches of the military and particularly close collaboration with infantry. Consequently, the Operation achieved its objectives of re-establishing the connection between the isolated capital of Republika Srpska and Serb-controlled southeastern territories, while also pushing Croatian forces out of northern Bosnia, all with relatively moderate losses. In the same battle, the opposing Croatian Army and Croatian Defence Council could muster fewer than 50 tanks, with just 4 M-84s among them. The VRS had 24 M-84 tanks at its disposal, as well as 92 other tanks.

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In another rare tank-on-tank engagement, one of these Croatian M-84s ambushed an M-84 (T-55 according to some sources) of the Army of Republika Srpska near Bosanski Brod, resulting in the crew becoming the final casualties of Operation Corridor 92.

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The Army of Republika Srpska also put to use leftover T-72M and M-84 tanks from the training schools in Banja Luka, Manjača, and Zalužani, including some from the zero and first series. These tanks were allocated to the 2nd Armored Brigade. In an interesting episode, a complete company of female tankers for the M-84 tanks was formed in the town of Kupres. However, due to their lack of training, the company was quickly disbanded, as it was decided that their skills would be more effectively utilized in field kitchens.

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M-84 - Tank Encyclopedia (157)

Throughout the early stages of the war, the Army of Republika Srpska maintained a relative superiority over its Bosnian and Bosnian Croatian adversaries. There were instances when the latter factions even turned their focus on each other rather than on Republika Srpska. However, the turning point occurred in 1994, when NATO initiated an air campaign against the Army of Republika Srpska. Simultaneously, Washington brokered a peace deal between the Croatians and Bosniaks, uniting them against their common Serbian enemy. Forced to fight defensively on all fronts, its international reputation tarnished by the Srebrenica massacre, Republika Srpska eventually succumbed, signing the Dayton Peace Agreement on 14th December, 1995, which marked the definitive end of the war in Bosnia and Herzegovina. Notably, the Republika Srpska acquired 23 M-84 tanks from the Serbian Army of Krajina that survived the fall of the Republic of Serbian Krajina.

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The immediate post-war period in the Republika Srpska was characterized by a gradual disarmament process, with much of the old and damaged equipment ending up on the cutting table under the watchful eye of SFOR. While the exact number of M-84 tanks retained by the Army of Republika Srpska at the end of the war is unknown, Srpski Oklop website lists 73 M-84 tanks in 1999, decreasing to 57 by 2004, just before the unification of the Armed Forces of Bosnia and Herzegovina.

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Army of the Republic of Bosnia and Herzegovina

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The Republic of Bosnia and Herzegovina would start the civil war on ‘hard mode’, with some sympathies from the international community but otherwise no real allies anywhere in the world. Despite the vast size of their newly established Army of the Republic of Bosnia and Herzegovina, it grappled with significant under-equipment, particularly in terms of heavy weaponry, such as tanks. The Bosnian Battle of the Barracks yielded minimal results, prompting the need to smuggle in weapons, primarily through Croatia. Predictably, the Army of the Republic of Bosnia and Herzegovina (Armija Republike Bosne i Hercegovine – ARBiH) experienced a series of defeats against the Army of Republika Srpska in 1992. The situation worsened in 1993, when the Republic of Bosnia and Herzegovina and the Croatian Republic of Herzeg-Bosnia turned against each other, leading to the effective closure of the only available supply route through Croatia.

The Army of the Republic of Bosnia and Herzegovina would capture and reuse a few armored vehicles, including just two M-84 tanks until near the end of the conflict. The first M-84 tank was captured from the 2nd Armored Brigade of the Army of Republika Srpska near Doboj in good condition on 30th November, 1992, after its track snapped and the tank got stuck in a ditch. This tank was recovered and was accepted into service with the 1st Tešanj Brigade. It earned the nickname “Garavi Zeko” (Black Rabbit), an amalgamation of the brigade’s nickname (Garava) and the nickname (Zeko) of one of the deceased tankers from the brigade. As luck would have it, this happened to be the ‘L1’ tank (registration number ‘21177’, chassis number ‘00006001T’) that had been previously prepared for shipment to Libya. Like with the other atypical M-84s, this tank had been sent to the training schools around Banja Luka once the export deal fell through.

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M-84 - Tank Encyclopedia (162)

“Garavi Zeko” played a key role in the capture of the second M-84 tank (registration number ‘21222’) in the early morning of 22nd August, 1993, near the town of Miljanovci, close to Tešanj. According to Amir Halep, the tank’s commander, the previous day, “Garavi Zeko” managed to score a hit on an unknown VRS tank and chase away an armored train sent from Doboj. In the evening, “Garavi Zeko” was dispatched to Miljanovci to disperse the VRS infantry guarding the M-84 tank that was previously disabled by the ARBiH forces. Once this was accomplished, early in the morning, the disabled tank was towed away by “Garavi Zeko” under the cover of friendly infantry. The captured M-84 tank had been previously disabled by an M80 Zolja shot into the area of the exhaust. Fortunately, the brigade had enough spare parts to repair it and put it back into action under the nickname “Sultan”. This tank was one of the M-84T tanks previously evacuated from Vrhnika.

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M-84 - Tank Encyclopedia (164)

The 5th Corps of the ARBiH managed to capture two M-84 tanks in 1995. The first one was captured in August near the village of Krivaja, near Cazin, during the offensive named Scorched Earth. Another tank was captured in September, close to Bosanski Petrovac in the Sana 95 Operation. Another M-84A may have been captured close to Bosanski Petrovac as well.

One first series M-84 tank (registration number ‘21110’, chassis number ‘00006-051D’) was also captured by the 5th Corps from the Serbian Army of Krajina. This tank was captured in July 1995, painted brown, and nicknamed “Pegasus”.

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M-84 - Tank Encyclopedia (166)

Additional M-84 tanks were either captured or recovered in the late stages of the conflict and after the Dayton Agreement, which ended the war. Before the merger of the Army of Republika Srpska into the Armed Forces of Bosnia and Herzegovina, the ARBiH had 6 M-84 tanks.

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Croatian Republic of Herzeg-Bosnia

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The Autonomous Region of the Croatian Republic of Herzeg-Bosnia was established to protect the interests of the Bosnian Croatians within Bosnia and Herzegovina. While de jure not separatist in nature, in practice, it was heavily influenced by Republic of Croatia and largely acted independently, and its armed force, called the Croatian Defense Council (Hrvatsko Vijeće Obrane – HVO), fought against the Army of the Republic of Bosnia and Herzegovina whenever it deemed necessary. Like the ARBiH, the HVO struggled to equip itself with heavy weapons. Out of approximately 50 tanks operated throughout the conflict, none were of the M-84 model. However, if stories are to be believed, one M-84 tank did see service on their side. This tank was reportedly rented from the Republic of Srpska to be used against the forces of ARBiH, who the HVO was also fighting at the time.

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Former Yugoslav Republic of Macedonia

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The Republic of Macedonia was the only Yugoslav republic to peacefully secede. Its independence referendum was not contested, leading to the declaration of independence on 8th September, 1991. With the Yugoslav People’s Army no longer serving as the armed force of the new Macedonia, it withdrew from the region. Although the Army of Macedonia did not inherit any M-84 tanks, the departing JNA left behind T-34/85 tanks as a parting gift. These tanks were used for crew training until Macedonia received T-55 tanks from Bulgaria.

Yugoslavian Army

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After the JNA pulled out of Bosnia, it lost its purpose, as the state it had served ceased to exist. The restructured Federal Republic of Yugoslavia, comprising only Serbia and Montenegro, transformed the remnants of the JNA into the Yugoslav Army (Vojska Jugoslavije – VJ). The Yugoslav Army was reorganized into three armies, encompassing seven corps and consisting of 34 brigades. It inherited the majority of JNA equipment, including 1,300 tanks, of which approximately 250 were M-84s, 568 IFVs, 1,200 cannons of all calibers, 200 MLRS, 1,665 mortars, 2,000 anti-aircraft cannons, 135 anti-tank launchers, and 60 anti-aircraft missile systems.

The M-84 tanks were concentrated in three formations:

  • 1st Guards Brigade in Belgrade
  • 211th Armored Brigade in Niš
  • 252nd Armored Brigade in Kraljevo

Additionally, some tanks were stationed at tank schools and training centers. The ground forces numbered around 85,000 personnel, while the air force, with 16,700 personnel, operated with 200 largely outdated aircraft and 50 helicopters. This new army would be tested in the final conflicts of the Yugoslav Wars, the insurgency in Kosovo and Metohija and the Preševo Valley.

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The situation in the Serbian autonomous province of Kosovo and Metohija became increasingly unstable following the federal crackdown against protesters in the 1980s. Throughout the second half of 1990s, passive resistance among Albanians seeking independence gradually transformed into an armed insurgency, fueled in part by the chaos unfolding in the Republic of Albania at the time. As Chinese-made weapons from the Albanian Armed Forces flowed into the province unobstructed, separatist terrorist organizations swelled in size.

The Kosovo Liberation Army (KLA) began operating in 1995, launching attacks on federal buildings, Yugoslav police forces, Albanian collaborators, and ethnic Serbian civilians. As the KLA’s activities intensified, particularly in spring of 1998, its controlled territory expanded to cover 40% of the province. This territory was primarily composed of mountain ranges, forests, and isolated villages, while major urban centers in the province remained under federal control but were effectively under siege.

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Since the overstretched troops of the Yugoslavian Ministry of Internal Affairs struggled to control the escalating situation in Kosovo and Metohija, the 3rd Army of the VJ was deployed to assist them in restoring order. In the initial stages of the conflict, tanks were deployed in single platoons, accompanied by a platoon of Infantry Fighting Vehicles (IFVs), and a few M53/59 Praga vehicles for fire support. While the JNA had experimented with tank platoons consisting of four tanks just before its dissolution, the VJ returned to the practice of having three tanks per platoon during the conflict. The only unit in Kosovo and Metohija equipped with M-84 tanks during this period was the second mechanized battalion of the 211th Armored Brigade, stationed at Podujevom, with the remainder of the Brigade being transferred to the area by the end of the year. However, tanks of the Battalion were employed sparingly, with a notable instance being the battle for Bajgora in late 1998. The decision to limit their use was strategic. The mountainous operational area with poor infrastructure was considered more suitable for the lighter, cheaper, and more numerous T-55 tanks. In the context of counter-insurgency warfare, the M-84s, except for their superior frontal armor, were seen as offering little additional advantage. Instead, the M-84s were held in reserve within the country, anticipating a potential confrontation with NATO.

Following the KLA’s unsuccessful attempt to capture the town of Orahovac, the Yugoslavian Army launched a counteroffensive, reclaiming much of the territory previously held by insurgents. The increasing humanitarian toll of the conflict prompted Western powers to pressure Yugoslavia to halt its campaign, which had led to the displacement of numerous Albanian civilians. In compliance with international pressure, FR Yugoslavia initially agreed to cease its operations. However, peace negotiations faltered when Slobodan Milošević refused to sign the controversial Rambouillet Agreement. In response, NATO initiated a bombing campaign on 24th of March, 1999.

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Three days later, the VJ high command decided to deploy the 252nd Armored Brigade to Kosovo and Metohija. The M-84 tanks of the Brigade were transported by trains, while supporting elements and trucks traveled by road. The excruciating journey took four days, as trains often had to be concealed in tunnels to evade reconnaissance drones and NATO aircraft. Tank crews remained inside their vehicles, prepared to disembark them off the flatcars and disperse them at a moment’s notice in case of an imminent air strike on the train. The 252nd Brigade successfully reached the town of Lipljan without any losses, earning the nickname “An Invisible Brigade.” With the addition of this Brigade, the total number of tanks in Kosovo rose to approximately 350. The majority of these tanks were concentrated in the 15th Armored Brigade (equipped with T-55s), along with the 211th and 252nd Armored Brigades (equipped with M-84s). The remaining tanks were T-55s located in the tank battalions of the 243rd Mechanized Brigade, and 78th, 125th, and 548th motorized brigades.

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M-84 - Tank Encyclopedia (176)

During the bombing campaign, the focus of NATO’s strike missions outside Kosovo and Metohija was on targeting infrastructure and industry. However, within the province, NATO also conducted close air support missions in support of the KLA, compelling the armored formations of the VJ to implement extensive camouflage measures. Tanks were dispersed to the greatest extent possible, with tanks from the same platoon positioned several hundred meters apart. In response to NATO’s reliance on thermal cameras, the practice of pre-heating the engines was prohibited, and tanks were not allowed to keep their engines running unless they were about to advance or change position. When tanks needed to move, they did so in “jumps” from one cover to another. Movements were typically carried out during the night or in bad weather conditions. If movement was necessary on a clear day, tanks moved while covered in fresh vegetation, with significant distance between them, often minutes apart. Tanks on the march were equipped with water tanks to spill water on the engine decks in case of an air alarm, cooling them down to reduce their thermal signature. An alternative approach involved placing a water-soaked blanket over the engine deck.

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Upon reaching a new position, each tank crew had to prepare multiple fallback positions and additional, more conspicuous fake positions, typically spaced between 500 and 1000 m apart. Tank tracks had to be covered or cleared unless leading to a false position, where a decoy target would be placed. In instances where damaged tanks or decommissioned T-34/85s, M4A2E4 Shermans, and M18 Hellcats were unavailable, the JNA improvised tank dummies. This involved covering cars or agricultural vehicles with sheet metal, wood, tires, and old camouflage nets. Tree trunks or unloading pipes from combine harvesters were left protruding through garage doors to create the illusion of a hidden tank. To enhance the realism, empty ammunition boxes and clothing store mannequins were arranged around the decoys. Occasionally, fires were lit in the engine compartment or gun barrel, or a stove was placed inside to simulate warmth. The effectiveness of decoys also relied on their visibility on enemy radars. Passive triangle-shaped radar reflectors were often utilized for this purpose, with two reflectors needed to simulate one tank. Typically, a cluster of around six reflectors would be strategically placed to mimic a tank platoon.

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These decoys were used until they literally fell apart, often sustaining multiple hits from precision projectiles during the conflict. It is estimated that 80% to 90% of all decoys were detected and hit throughout the war.

The 78-day NATO bombing campaign concluded following the signing of the Kumanovo ceasefire agreement. Despite around 3,000 sorties targeting mobile assets, only 1,995 were initially considered successful. Of these, 181 strikes were directed at tanks, with 93 tanks believed to be disabled or destroyed. Yugoslavia reported the loss of 13 tanks throughout the entire war, including 9 M-84s. However, post-war assessments, such as the one carried out by Munitions Effectiveness Assessment Team, identified only 14 destroyed tank hulls in Kosovo and Metohija. The lower estimates of destroyed Yugoslavian armor are underscored by the fact that the modern Serbian Armed Forces still possess 232 M-84 tanks, with another undisclosed number earmarked for training and modernization projects.

On 2nd April, 1999 M-84 tanks from the 252nd Armored Brigade were caught while refueling in the open, becoming targets for multiple bombing and cluster bombing strikes. Six personnel lost their lives, and four tanks were damaged or destroyed. On 2nd May, three more M-84s belonging to the 252nd “Tactical Group” were lost. Due to inadequate camouflage, two tanks were identified and subsequently targeted by NATO aircraft. A third M-84, attempting to conceal itself in a garage, was destroyed because the crew failed to clear the track marks leading to its location.

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The last engagement involving M-84 tanks was the Battle of Oraovica, a confrontation between the Yugoslav Army and the Liberation Army of Preševo, Medveđa, and Bujanovac (UÇPMB). Serbian Special Forces, accompanied by tanks from the 211th Armored Brigade, effectively recaptured the insurgent-controlled town in southern Serbia without incurring any losses.

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Service Outside of Yugoslavia

Kuwait Army

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The first Kuwaiti M-84 tanks were lost in unclear circ*mstances. Either four or more likely six M-84 tanks of either second, third, or fourth series were sent to Kuwait just before the Iraqi invasion in 1991. According to some sources, they were used by the Emiri Guard in the defense of the palace. All of these initial Kuwaiti M-84 tanks were either destroyed or captured, with at least one good condition M-84 being captured by Iraq.

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Due to the Iraqi occupation of Kuwait, the M-84ABs had to be redirected to Saudi Arabia, where the Kuwaiti government in exile was stationed. By 6th February, 1991, 71 M-84AB tanks had arrived in Saudi Arabia and equipped the 35th Al-Shaheed Armored Brigade. These tanks saw limited action during Operation Desert Storm, performing well and sustaining only minor, repairable damage. Additional deliveries increased the number of M-84AB tanks in Kuwait to 149. However, due to the collapse of Yugoslavia, the contract had to be canceled and further deliveries came to a halt. Besides training and parades, Kuwaiti M-84ABs have not seen action since the conclusion of the war with Iraq.

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Iraqi Republican Guard

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During the Victory Parade in Baghdad on 31st December, 2000, the Iraqis showcased a captured M-84 tank. It remains unclear whether this was the only captured example or if there were more. Some sources, albeit unreliable, suggest that four tanks were destroyed during the Iraqi invasion, and two were captured from Kuwait.

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At least one captured M-84 tank, potentially the same one from the Baghdad parade, seems to have been used by the Republican Guard during the 2003 Iraq War. It is unknown whether the tank saw action during Operation Desert Storm before that. One of the Iraqi M-84 tanks is also said to have been recaptured and repaired by American forces and is currently used for OPFOR training, either at Fort Bliss, Fort Moore (formerly Fort Benning), or Fort Cavazos (formerly Fort Hood).

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Combat Performance Assessment

It is not easy to gauge the performance of the M-84 tanks during the wars they participated in. At times, they were used incompetently, as seen during the early JNA operations in Slovenia and Croatia. At other times, their usage was atypical, such as in the post-1992 Croatian Civil War and Bosnian Civil War. In certain conflicts, like Kosovo and Metohija and Operation Desert Storm, they were barely used at all.

Rarely were the M-84s concentrated and employed in well-thought-out combined arms offensives with ample infantry and air support, as seen in operations such as Corridor 92 and Operation Storm. In those cases, the M-84 proved to be a powerful tool for those capable of wielding it, but in the grand scheme of things, these operations were infrequent. More commonly, the tanks functioned as static fire support, rolling up to the pre-prepared firing positions on the frontline, unleashing hell upon the enemy, and then retreating upon task completion.

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Before offensive operations, the tanks conducted their own artillery preparation, firing for hours at a time toward a target while continuously being resupplied with ammunition, before moving to capture the target in conjunction with infantry. Strangely enough, because they were used this way, tanks were often captured on the frontlines, and sometimes entire battles were fought over a single tank abandoned on a good firing position. Tanks damaged at the frontline had to be recovered quickly, else they would find themselves stolen by the other side or peppered with anti-tank fire until they became unusable. Some JNA M-84s disabled in the Vukovar area suffered dozens of hits from light anti-tank launchers, rendering them useless by the time the area was secure enough for recovery.

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The main reason why tanks were employed in such an unorthodox way can be attributed to commanders allowing their forces to disperse over a wide operational area instead of maintaining concentration. For example, at one point in 1992, the 2nd Battalion of the 1st Armored Brigade of the Army of Republika Srpska found itself defending 10 different locations in Posavina, none of which were in proximity to each other. The standard JNA doctrine, which emphasized three tanks forming a platoon and three platoons plus a command tank constituting a company, was quickly abandoned. Instead, individual tanks were given names and used as basic units. In some cases, the mere presence of a tank provided a morale boost among infantry, far outweighing the actual combat value of the lone vehicle.

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Ironically, the M-84’s main advantage, its modern fire-control system, became nearly irrelevant in the context of the conflicts in the territory of ex-Yugoslavia. Most of the fighting during these wars occurred at close range, and long-distance fire was often approximate at best. Tank-on-tank duels were extremely rare, and the majority of projectiles fired were HE-FRAG rounds. Other ammunition, such as HEAT, was only used when HE-FRAG rounds were unavailable. The true advantage of the M-84 tanks turned out to be their ability to withstand fire from light anti-tank weapons better than any other available tank. In the field, crews sometimes made modifications to their machines to further enhance their defensive capabilities. For example, in the Army of Republika Srpska, it became a standard practice to add extra rubber skirts and weld empty ammunition boxes filled with rubber to the front of the tank. While these ad hoc modifications instilled confidence in tank crews, their practical effectiveness remains questionable.

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M-84 - Tank Encyclopedia (194)

Damage Assessment and Repairs

The most common type of damage suffered by M-84 tanks was from light anti-tank launchers like the Armbrust and M80 Zolja. While these could not penetrate the front of the tank, they often found their mark when fired from the sides or rear. Tanks damaged by these light anti-tank launchers were rarely complete write-offs. Most of them were successfully repaired and reintroduced into service, with some tanks undergoing repairs multiple times. Notably, one fourth series M-84, registration number ‘21316’, endured six hits from Zoljas, and each time it was repaired and put back into active duty.

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M-84 - Tank Encyclopedia (196)

Until the commencement of the NATO bombing campaign, no M-84 tanks were lost to airpower. Some tanks were lost to mines and very few fell in tank-on-tank combat. One such instance involved M-84 tank number ‘21423’, which participated in Operation Corridor 92 within the Army of Republika Srpska. This tank was struck by a Croatian T-55, resulting in two indentations on the left side of the front plate. Although the tank’s interior remained undamaged, the hull suffered deformation from the impact, and it had to be scuttled. The turret from this tank was later mounted on the M-84 tank that experienced a barrel launch due to an exploded shell in the breach—a mishap attributed to inadequate gun maintenance by the crews, which was another common reason for the loss of a tank.

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The case of M-84 number ‘21318’ is interesting, and highlights the chaotic and unpredictable nature of warfare. The tank, originally part of the war reserve in Vrhnika, found itself involved in a unique incident during autumn of 1991 in Slavonia, Croatia. After the capture of a Croatian village, the crew of the M-84 tank reportedly left the vehicle to participate in looting. Seizing this opportunity, a Croatian tank crew hiding in a basem*nt jumped into the empty M-84 tank and attempted to drive it away. The JNA responded by opening up on them with everything they had, including a 120 mm mortar that somehow scored a direct hit on the runaway tank. As a result of the damage sustained, the tank underwent a lengthy and challenging 8-month repair process but was nevertheless fixed and put back into action.

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In early 1994, this same tank was once again hit by a mortar round, this time near the end of the gun barrel. With no available spare 125 mm guns, a decision was made to address the issue by shortening the damaged barrel by 243 mm. This was done on 2nd February, 1994, in the TAS (Tvornica Alatnih Strojeva – Machine Tool Factory) enterprise in Banja Luka. To compensate for the reduction in weight, a counter-weight was installed at the end. While this modification allowed the tank to remain in service, the effective firing range of the tank was decreased to about 1 km.
Corruption was another unfortunately common reason for the loss of a tank. Some tanks that could have been feasibly repaired and returned to service were instead unjustly deemed irreparable, and sold as scrap metal.

Foreign Interest and Testing

Soviet Union

As per the licensing requirements, one tank was sent to and another one was bought by the Soviet Union for testing purposes. The first series tank was returned, while the second series tank was retained and is currently located in the Kubinka Tank Museum in Russia. That tank is in a driveable but otherwise poor state. It does not have a battery so for it to be turned out it has to be pulled by another tank.

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Soviet reports highly rated the build quality, the fire-control system, and the night-fighting capabilities of the M-84 during their tests.

State of Libya

Early on, the sale of tanks to Libya was already a foregone conclusion. Libyan generals closely monitored the tank’s development and production, and Libyan tank crews were already undergoing training in Yugoslavia by 1985. It is possible that Libya even made advance payments for the first batch, which is why the engineers were pressured to finish the job as soon as possible. In 1983, during one of the initial live-fire tests of the new M-84 tank, there was not enough time to finalize the fire-control system. Since the entire presentation was arranged for the Libyan delegation, it was deemed unacceptable for the new tank to miss the target. A clever solution was devised. Soon after the demonstration began, the M-84 was parked behind some large bushes, and out of them came a T-72M, which subsequently completed the firing trial by hitting a tank wreck at 1,500 m (0.93 mi). To enhance the explosion’s impact, the wreck was filled with explosives and gasoline the day before. The Libyan delegation left satisfied, and orders were placed for the production of 40 second-series M-84T tanks. Libya initially intended to purchase 1000 tanks, later revised to 200. However, none were ever sent, as this promising business opportunity fell through due to the combination of Libyan belligerence on the global stage and the Soviet Union outbidding Yugoslavia with a better deal. The ‘L1’ tank ended up in the Army of Republika Srpska, captured later by the Army of the Republic of Bosnia and Herzegovina, while the ‘L2’ most likely went to the Serbian Army of Krajina. The 40 tanks designated as war reserve were stationed at Vrhnika, Slovenia, with half remaining there and the rest evacuated to Republika Srpska, joining the ranks of its army.

Republic of India

In 1988, Rudi Čajavec factory adapted a T-72M with the SUV-M-84, and this modernization was offered to the Indian Army. Following successful testing, the Indian Army placed an order for 1,000 kits for the T-72 tanks and another 1,000 for the T-55s. There were expectations that this business deal would lead to India ordering M-84 tanks and subsequently acquiring the production license from Yugoslavia. However, the collapse of Yugoslavia canceled all such plans, the money was embezzled and no kits were ever sent in the end.

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Islamic Republic of Pakistan

The Pakistani Intelligence network swiftly learned of the Indian Army’s order for the SUV-M-84 kits. In response, the Pakistani Army, seeking to maintain parity with its rival, requested to test the M-84A tank. Two tanks, designated ‘P1’ and ‘P2’, were dispatched and arrived in Pakistan in August 1990. This operation was conducted in strict secrecy to avoid angering the Indians, which could jeopardize Yugoslavian business ventures with them. The maintenance standards set for these tanks were extremely rigorous, ensuring that they arrived for testing in perfect condition.

Following a brief oral presentation, the tanks underwent rigorous testing with Pakistani crews. They traveled 1,600 km in temperatures ranging from 45°C to 50°C, enduring sandy and marshy soil conditions. The tank’s abilities in regards to water fording, self-entrenchment, smoke screen laying, and towing another tank were also tested. Despite the harsh conditions, there were no breakdowns or oil leaks. The M-84As demonstrated high accuracy on the firing range, with crews reporting an 80% hit rate regardless of the weather and time conditions. The domestic RUT-1 radio kit performed exceptionally well, prompting the Pakistan Army to consider placing a separate order for them.

Ultimately, the tanks passed all trials with flying colors, and the Pakistan Army expressed interest in ordering 200 tanks and obtaining a production license for another 1,000. The total cost of the deal was estimated to be between US$3 and US$4 billion. However, Pakistan was prepared to pay under the condition that 30% of the deal be paid in cotton, a condition which the Yugoslavian delegation refused. Unfortunately, the outbreak of war in Yugoslavia, as with India, brought an end to all further negotiations with Pakistan. The ‘P1’ and ‘P2’ tanks were returned to the Đuro Đaković factory.

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Islamic Republic of Iran

Yugoslavian relations with Iran were distant, since Yugoslavia sought to maintain good relations with its rival, Iraq. Nevertheless, Yugoimport began eyeing the country as a potential export destination for weapons since February 1989, when the first cooperation agreement between them and the government of Iran was signed. Nine months later, an offer was made for technology transfer, license for the production of 1,000 tanks, and technical assistance with getting the production off the ground for a price of US$2.5 billion. This price was based on the price for the previous sale of tanks to Kuwait. Not all parts were to be produced in Iran, as around 30% assemblies and aggregates would have to be imported from Yugoslavia. Other countries also made their offers, and the Iranian commission eventually narrowed down the choice to the Yugoslav M-84 and the Russian T-72S. What held the M-84 back was the fact that it could not fire anti-tank guided missiles (ATGMs) through its main cannon like the Soviet tank, and more importantly, the price, which Iran was unwilling to pay. Yugoimport was ready to compromise, and negotiations continued throughout the 1990s, but like with other deals, the collapse of Yugoslavia put an end to all negotiations, leaving Iran to accept the Russian offer.

Current Operators and Modernization Programs

Republic of Serbia

As the primary inheritor of the vast JNA arsenal, the Serbian Army today operates more M-84 tanks than any other entity. Montenegro, which peacefully separated from Serbia in 2006, inherited no M-84 tanks.

Following the post-war army reform, the 211th and 252nd Armored Brigades were reorganized into four tank battalions: the 15th, 26th, 36th, and 46th, which were subsequently integrated into the four army brigades.

Officially, each brigade possesses a tank battalion with 53 tanks, along with another 20 tanks in reserve, making for a total of 232 tanks, 28 of which are M-84As. Unofficially, a couple more tanks are likely to have survived the wars and scrapyards and are currently used for training, R&D, and by Yugoimport for marketing. Throughout the years, there have been multiple attempts to develop modernization packages for these tanks.

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M-84AB1

The first attempt, the M-84AB1, was a venture project undertaken by Yugoimport in the early 2000s, banking on potential sales to Kuwait, which would in turn fund the modernization of Serbia and Montenegro’s own tank forces. As post-war tank development basically had to start from scratch, the M-84AB1 modernization package was developed with ample help from Russian and Ukrainian tank manufacturers, bringing the M-84 MBT to the standard of the early T-90S export tanks.

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The defensive capabilities of the M-84AB1 were improved with the incorporation of several advanced systems. These included the Kontakt-5 explosive reactive armor, which provided enhanced protection against anti-tank threats. Additionally, the Shtora-1 soft-kill passive protection system was integrated, capable of disrupting semi-automatic command-to-line-of-sight (SACLOS) anti-tank guided missiles.

To further bolster its defensive capabilities, the M-84AB1 was equipped with laser warning receivers and passive radar warning receivers. These systems provided the crew with early detection and warning of incoming threats, allowing for timely countermeasures. The firepower of the M-84AB1 saw notable improvement with the introduction of a new gun that offered enhanced field replaceability and the capability to fire anti-tank guided missiles. Furthermore, the fire-control system was entirely replaced and the crew also benefited from multiple new thermal imagers, cameras, and the new TOMS panoramic sight, improving their situational awareness.

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M-84M

After the rejection of the M-84AB1 by both Kuwait and Serbia and Montenegro, a new, cheaper modernization package was developed by TRZ (Tehnički Remontni Zavod – Technical Overhaul Workshop) “Čačak” in 2009. This variant, named M-84M (sometimes referred to as M-84S), was based on the M-84 tank, unlike the M-84AB1, which was based on the M-84A, and comprised largely domestic components. One of the most visible differences was the addition of the domestic KAO-M99 explosive reactive armor, equivalent to the Soviet Kontakt-1.

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The 780 hp (574 kW) engine was modified with a new fuel injection system and a high-pressure fuel pump, increasing its power output to 840 hp (626 kW). While the main gun remained the same, it received a new, thick, thermal sleeve of questionable construction since it probably ruined the balance of the gun. Additionally, the PKT coaxial machine gun was paired with a device known as a “fire regulator,” providing the gunner with more control over the weapon.

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Other enhancements included the addition of new firefighting equipment and longer rubber skirts for improved protection. Though the M-84M was also initially rejected, it would continue to be developed and evolve throughout the years.

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M-84AS1/AS2

In 2017, a modified version of the M-84M was showcased during the Partner Military Exhibition as the M-84AS1. This iteration of the tank underwent a more extensive modernization, including thermal imagers for both the gunner and commander, addition of slat armor around the engine compartment and Kontakt-5 panels on the sides, new ammunition, radio equipment, radar warning receivers and other electronics. Despite its participation in the Steel 2017 military exercise and the announcement of its adoption into service, the tank’s adoption was not finalized. It appears that the Army decided to delay its introduction to await the completion of the new explosive reactive armor in development at the time.

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The first modernization package accepted for service was the M-84AS1/AS2, unveiled in 2020. Unlike the previous prototype that shared the same name, this latest version of the tank underwent a comprehensive redesign. It featured an entirely new ERO-19 explosive reactive armor system, along with the integration of two dozen other new subsystems. These included the addition of 360° low-light cameras and a new commander’s panoramic sight, among others.

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The M-84AS1 and M-84AS2 upgrade packages have minor differences, with the latter being accepted for service and marked for serial production. Currently, the first 26 tanks are undergoing modernization to this standard, with 12 of them already completed at the time of writing (March 2024).

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Hibridni Artiljerijsko Raketni ProtivAvionski Sistem

The HARPAS (Hibridni Artiljerijsko Raketni ProtivAvionski Sistem – Hybrid Artillery Missile Anti-Aircraft System) deserves special mention as the only currently active conversion project for the M-84 tank hull. Developed as a dedicated anti-aircraft system for mechanized formations equipped with tracked vehicles, the HARPAS was first unveiled in 2023 during that year’s Partner Military Exhibition. It is armed with two 40 mm Bofors L/70 anti-aircraft cannons and two pairs of domestic RLN-TK and RLN-RF anti-aircraft missiles. According to Dr. Nenad Miloradović, two Bofors cannons were mounted because one was deemed insufficient against drone swarms, which this vehicle is expected to face. The weapon systems on the HARPAS are paired with the Thales Ground Smarter GS-40 radar, mounted on top of the vehicle.

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Republic of Croatia

The Croatian Army currently possesses 75 M-84 tanks, though as with Serbia, there may be additional tanks not officially counted in this figure. It is hard to estimate how many tanks the Croatians captured, and how many they produced for themselves. Some sources suggest that the Croatian Army ended the war with 27 M-84 tanks. Production estimates on the higher end place the total post-independence (wartime and post-war) production at over 50. Journalist Milan Jelovac, in 2001, mentioned that more than 650 tanks were left at the Đuro Đaković factory in total, aligning with this figure. The final production contract for 20 M-84A4 tanks was signed in 1999 with the Croatian Ministry of Defense, and the last two were delivered in June 2003. The subsequent planned contract for M-84A4 tank production was canceled, shifting the focus to the acquisition and maintenance of new Patria AMV armored personnel carriers.

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The Croatian M-84 tank fleet is the best maintained one, largely thanks to the presence of the Đuro Đaković factory in the country, which is in charge of their maintenance. It is also the youngest one on average, with most tanks produced after the war using parts imported from Eastern European countries formerly part of the Soviet Union or the Warsaw Pact. The Croatian Army operates perhaps the most diverse M-84 tank fleet, including T-72 tanks converted to the M-84A4 standard, captured M-84 tanks from the first, second, third, and fourth series, M-84A tanks taken from the JNA, M-84AB tanks produced for Kuwait but never delivered, and a number of locally produced M-84ABs with foreign parts. By the end of the decade, the majority of tanks had been converted to the M-84A4 standard. All Croatian M-84 tanks are part of the Armored-Mechanized Guard Brigade.

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M-84A4 Sniper

Development of the new Croatian variant of the M-84 tank began during the civil war, and the first prototype of the new M-84A4 Sniper was produced in 1996. The main difference between the new variant and the M-84 tanks from which they were often converted lies in the EFCS3-84L (Enhanced Fire-Control System, sometimes nicknamed Omega-84) developed by the Slovenian company Fotona. This upgrade was likely implemented due to challenges in maintaining and replacing damaged components of the original SUV-M-84 system after the dissolution of Yugoslavia. Similar to the DNNS-2A, the new SGS-84 (SGS-84L, SCS-84 in other sources) gunner’s sight on the M-84A4 Sniper tanks features three channels: a day channel, a night channel with second-generation image intensifier, and a laser channel for the rangefinder, capable of measuring distances of up to 10 km.

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While the exact specifications and capabilities of the EFCS3-84L system are not fully known, it would be almost certainly be incorrect to simply label it as a flat upgrade over the old SUV-M-84 system, considering that the EFCS3-84L started out as a budget fire-control system for the JNA T-55 tanks before undergoing further development by Fotona to bring it up to the level of the SUV-M-84.

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The M-84A4 Sniper tanks began to be equipped with “LIDR” (Laser Identification and Detection Receiver) laser warning receivers manufactured by Fotona in the second half of the 1990s. The engine powering the M-84A4 tanks was never specified, but it is likely that they use either the old V-46-6 and V-46-TK engines or similar T-72 engines imported from abroad. Additionally, the radio stations used in the M-84A4 Sniper tanks are a mix of old ones produced by Rudi Čajavec and foreign ones, such as the Racal Dana radio sets used in Kuwaiti tanks.

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M-95 Degman

Compared to Serbia, Croatia benefited far more from the development done on the M-84 tank and its successor Vihor before the collapse of Yugoslavia, and even continued the development for a short while afterward. The result of this development was the M-95 Degman and the M-84D upgrade package for the M-84 tank.

The M-95 Degman utilized one of the two Vihor hulls that were left in Croatia, but features a new larger turret of welded construction powered by an all-electric drive. The exact thickness and composition of the turret are unknown, but considering the new tank had a weight of 46 tons, 2 tonnes heavier than the M-84A, its protective capabilities are unlikely to be worse than its predecessors. Furthermore, to enhance protection, the front and sides of the turret and hull are covered in RRAK explosive reactive armor, developed and supplied by the Israeli company RAFAEL Advanced Defense Systems.

The main armament remained the same 125 mm gun, while the fire-control system is Fotona‘s Omega-D, equipped with an SGS-D gunner’s aiming device comparable to the one found on M-84A4 tanks, although the TSGS-D sight with thermovision is also stated as an option. The commander has the ability to take over or override gunner’s controls and perform his activities, including target engagement, via his COMTOS system integrated into the DNKS-2 sight.

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The Degman also features new German tracks, the addition of the LIRD laser warning receiver, new domestic NBC and fire suppression systems, and CODRIS-E periscope for the driver. One aspect that was not improved is the engine, as the tank uses the V-46-TK engine, the same one as on the M-84A tanks. However, considering the weight of the Degman rose by only 2 tonnes, that should not be too much of a problem.

At most, two M-95 Degmans were ever made, with one being completed in 2003 and another one possibly being completed in 2008. Although the Đuro Đaković factory signaled its readiness to commence mass production, no orders for this tank were ever placed.

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The M-84D modernization package was initially conceived as a proposal to modernize Kuwaiti tanks. It integrated numerous solutions previously developed for the M-95 Degman tank, including improvements to the fire-control system and the integration of RRAK explosive reactive armor. One tank was modified and offered to Kuwait as a modernization proposal for their own tanks. Unfortunately, Kuwait rejected the proposal, and despite sporadic interests from the Croatian Army only, no tanks were ever ordered, and only one M-84D tank appears to have been converted. This tank has been tested with multiple different remote controlled weapon stations.

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M-95 Cobra ATGM Carrier

The experimental M-95 Cobra ATGM carrier vehicle is noteworthy, as it was developed based on an M-84A4 tank hull. This vehicle features a custom turret equipped with hatches, a Zastava M87 machine gun, smoke launchers, and a crane. The crane has the capability to extend its bucket up to a height of 14 m, enabling the Cobra to engage targets with its 9K111 fa*got ATGM while remaining hidden behind cover. Only a single prototype-demonstrator of the M-95 Cobra was built.

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Republic of Slovenia

Slovenia currently operates a total of 54 M-84 tanks. Out of these, only a single company comprising up to 14 tanks is in active use, while the remaining tanks are in reserve and stationed at Pivka. The active company often participates in NATO exercises, often playing the role of the “aggressors.” Additionally, some Slovenian tanks have been stationed in Germany exclusively for this role.

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All Slovenian tanks have been upgraded to the M-84A4 standard, which includes several improvements. These upgrades include the installation of the EFCS3-84L fire-control system developed by Fotona in 1996, the integration of the LIDR laser warning receiver, and the implementation of two new radio stations for improved communication capabilities.

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Fotona continued the development of this fire-control system, and one M-84 (registration number ‘10135’, note: this is not a JNA assigned number) was equipped with the experimental TFCS3, which in addition to the SGS-84 sight also features a separate STIGS-84 sight equipped with the thermovision channel. COMTOS commander’s takeover system and CODRIS-E driver’s sight were also installed on this tank. The laser warning receiver installed on this tank was designated LIRD-3A.

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Two observable drawbacks of this tank were the fact that the main sight was moved to the left, possibly causing discomfort to the gunner. The gunner’s periscope also had to be relocated, so that it now looks further to the left than on the base variant of the M-84 tank, possibly negatively affecting his situational awareness.

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Unfortunately, this sole prototype appears to have been taken apart, and only the chassis of this modified M-84 tank now remains.

Bosnia and Herzegovina

The Armed Forces of Bosnia and Herzegovina were formed following the amalgamation of the Army of the Federation of Bosnia and Herzegovina and the Army of Republika Srpska in 2005. Upon the disbandment of these respective armies, both entities within Bosnia and Herzegovina were permitted to retain some of their equipment as their own property. For the Army of Republika Srpska, this included the majority of their M-84 tanks, which had been part of the 101st Armored Brigade of the VRS up to that point.

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The Armed Forces of Bosnia and Herzegovina currently operate 16 M-84 tanks, with the majority stationed at Manjača. This number includes five tanks from the second series, one from the third series, four from the fourth series, and five M-84A tanks. Additionally, there is one decommissioned M-84A at Manjača. One active first series M-84 tank is also present in Derventa.

The remaining M-84 tanks, totaling 45 to 50 units, including 15 M-84A tanks, belong to the Republika Srpska and are located at Kozara barracks. Unfortunately, these tanks have been heavily looted, rendering them useless.

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A few M-84 tanks belonging to the Federation are located in Lukavica and Nedžarići.

The Armed Forces of Bosnia and Herzegovina, due to their limited budget, utilize these tanks very sporadically. In fact, there have been no live-fire exercises involving these tanks for a period of 20 years, starting from 1997 until 2017, when two tanks participated in an exercise on 16th and 17th March.

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State of Kuwait

The Kuwait Army still has M-84AB tanks, with all 149 delivered units presumed to be in their possession. However, these tanks were withdrawn from active service after an incident during the 2011 Kuwait National Day parade, when one of the tanks broke down.

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Conclusion

For a modest price, coupled with a considerable amount of effort, skill, and optimism, Yugoslavia was able to create a competitive, domestically produced main battle tank. If the country had not collapsed, the M-84 could have continued to evolve and be sold, potentially becoming a backbone of multiple armies around the world. Unfortunately, history took a different turn, and these tanks were instead used in conflicts between the republics that used to build it.

Combining all the numbers from above, a figure of approximately 575 tanks that are still accounted for can be reached, indicating that around 25 to 75+ tanks (depending on the final production number) were lost, scrapped, or otherwise unaccounted for. The responsibility for the maintenance and development of M-84 tanks now falls on the independent nations that previously comprised Yugoslavia. However, with respect to their efforts, these nations are unlikely to ever match the resources and capacities that SFR Yugoslavia once provided.

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M-84/M-84A Specifications

DimensionsTotal length 9.53 m
Hull length 6.96 m
Width 3.46 m
Height 2.19 m
Ground clearance470 mm
Total weight, battle-ready41,5 tonnes (M-84)
42 tonnes (M-84A)
Armor(M-84A)
Turret: 410 mm RHA
Hull: 80 mm plate + 105 mm textolite + 20 mm plate
(M-84A)
Turret: 410 mm RHA + 115 mm of composite material
Hull: 16 mm plate + 60 mm plate + 105 mm textolite + 50 mm plate
Propulsion780 hp V-46-6 (M-84),
1,000 hp V-46-TK (M-84A)
Top Speed60 km/h (M-84)
65 km/h (M-84A)
SuspensionTorsion bar, shock absorbers
TransmissionManual, 7 forward, 1 reverse gear
Fuel capacity1,600 liters (M-84)
1,450 liters (M-84A)
Range700 km on-road, 460 km off-road
Armament125 mm smoothbore 2A46 cannon with 43 rounds
12.7 mm Zastava M87 with 300 rounds
7.62 mm PKT with 2000 rounds
Crew3 (commander, gunner, and driver)

Sources

Razvoj Našeg Naoružanja – VTI kao sudbina – Prof. dr Milorad Dragojević

Tenkovi I Tenkovske Jedinice – Grupa Sovjetskih Autora

Mr. Vladimir Ivanović

Smrt Oklopne Brigade – Oklopno-mehanizirane postrojbe JNA u ratu protiv Republike Hrvatske – Davor Marijan

http://www.vti.mod.gov.rs/index.php?view=actuality&type=reference&category=4&id=128

http://www.vti.mod.gov.rs/index.php?view=actuality&type=reference&category=4&id=129

https://thesovietarmourblog.blogspot.com/2015/05/t-72-soviet-progeny.html#tpn

https://thesovietarmourblog.blogspot.com/2017/12/t-72-part-2.html#6010550

http://www.srpskioklop.paluba.info/

https://www.mycity-military.com/Oklopna-tehnika/Tenk-M-84.html

Ex-Đurko Đaković production manager, going by the forum name S. Palestinac

Ex-tanker, going by the forum name Jester

http://www.army-guide.com/

https://www.yugoimport.com/en

https://www.paluba.info/smf/index.php?topic=1473.0

http://fofanov.armor.kiev.ua/Tanks/ARM/apfsds/ammo.html

https://web.archive.org/web/20160304115510/http://www.ddsv.hr/download/Tenk_M-84A4_engleski.pdf

https://web.archive.org/web/20070105041218/http://www.ddsv.hr/tenk_degman.html

https://web.archive.org/web/20110919171436/http://www.ddsv.hr/download/tenk_degman_hrvatski.pdf

https://ddsv.hr/en/tenk.php

https://web.archive.org/web/20140211190113/http://www.duro-dakovic.com/_Data/Files/01.pdf

https://web.archive.org/web/20120226141522/http://hr.aalan.hr/Katalog/tabid/3637/articleType/ArticleView/articleId/11583/Main-Battle-Tank-Upgrade–Overhaul–Retrofit.aspx

[PARTNER 2023] Ministarstvo odbrane za Tango Six: Zbog čega projekat novog domaćeg hibridnog artiljerijsko-raketnog sistema PVO HARPAS

https://archive.org/details/IraqiArmyEquipment1930-2017SpecialReportVol.2/page/n11/mode/2up

https://forum.warthunder.com/t/m-84-tfcs3/9194

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