M-84

In the area of combat vehicles, the Military Technical Institute of the Republic of Serbia [VTI] has been engaged in developing tanks, armored personnel carriers, infantry fighting vehicles and their modifications. The Institute started with tank development in 1954 after the decision had been made at the highest level to develop a domestic medium tank. Based on the Institute�s own design solution and on the best tank from WWII, T-34, two different prototypes, M-628 and M-636, were produced. All further activities concerned the M-636 model. The experience gained in these projects was invaluable for the creation of expert scientific staff who later worked on a top quality M-84 tank.

The M-84 tank is a Yugoslav-built version of the Soviet T-72. Though lacking many of the modern features used by Western tanks, such as sophisticated fire control and communications equipment, it has computerized fire control system and vehicle optics.

The Yugoslav government purchased license production rights in 1979 and the first prototypes were completed in 1982.The Polish/Czechoslovak development pattern was followed, with some differences, in Yugoslavia. There was some delay in series production due to the decision to incorporate an indigenous fire control system into the vehicle. This included the DNNS-2 day/night gunner's sight, a wind sensor mast located on the turret roof above and behind the main gun, and a computerized fire control system. It was designated M-84 when it entered production at the end of 1984.

In the late 1980s, the improved Obiekt 172M-1 turret was incorporated into the design, providing local fire control improvements and an uprated engine, resulting in the M-84A. A total of 502 M-84 and M-84A tanks had been produced for the Yugoslav National Army by the time of the 1991 civil war. Additional production included at least one sample for the USSR. Kuwait ordered 200 M-84s in 1989, including 15 command tanks and 15 ARVs. These vehicles had a variety of small improvements to make them more suitable for use in the desert, and they were designated M-84AB. About 12 had been delivered before the Iraqi invasion in 1990, and during the war, an additional shipment was made to the Kuwaiti 35th Fatah Brigade.

A substantially modernized T-72 derivative, called the M95 or V-2001, entered development for the SDPR (Federal Directorate of Supply and Procurement) in 1990. This program was delayed by the Yugoslav civil war and the ensuing economic embargo and may be canceled. The main M-84 plant (Djuro Djakovic in Slavonski Brod, Croatia) is no longer manufacturing this tank; the attempted to restart production at the "14 Oktobar" plant in Krusevac.

The tank features two banks of smoke dischargers mounted on the turret front, seven on the left and five on the right, and a distinctive meteorology mast containing sensors fitted on the forward part of the turret. A powerful 1000 hp diesel engine gives greater acceleration, higher road speed and improved power-to-weight ratio. Ballistic protection is achieved by a low profile of optimum shaping and a multi-layer "sandwich" armour with equivalent penetration resistance exceeding 600 mm. M-84 tank is capable of fording water obstacles 1.8m deep and, in underwater drive, up to 5 m deep. This vehicle is not normally suited for operation on terrain of the type around Kosovo.

Battle tank M-84A is military vehicle with cross country mobility, weight 42 tons, three men crew (commander, target operator and driver), 9530 mm length (gun forward), width 3590 mm, height 2190 mm, clearance 470 mm and nominal pressure on the ground of 0.813 bar.

The basic armament of M-84 tank consists of smooth bore main gun 125 mm with firing range of 360� and 6�13' / +13�47' on height. Firing speed of 8 shells per minute with maximum range of 10 km is ensured by automatic loading system of 22 shells in mobile conveyor with automatic selection of kind of ammunition. The battle set of the gun consists of three kinds of ammunition and 42 two-part bullets: Explosive-piercing ammunition (TF, HE), designed for annihilation of light fortified objects, non-battle vehicles and infantry, mass 33 kg, initial speed 850 m/s and targeting distance of 6000 m. Cumulative ammunition (KM, HEAT), designed for anti-armor battle, mass 29 kg, initial speed 905 m/s and targeting distance 4000 m. Sub-caliber ammunition (PK, AP-FSDS), designed for anti-armor battle, mass 19.7 kg, initial speed 1785 m/s and targeting distance 4000 m.

Machine gun PKT, caliber 7.62 mm, coupled with gun, with targeting distance 1800 m achieves real firing speed of 250 bullets/minute; battle set consisting of 2000 bullets. Antiaircraft machine gun NSV caliber 12.7 mm mounted on the commander turret and manually controlled for 360� in direction and -5� / +75� on height with targeting distance of 2000 m achieves the real firing speed of 680 to 800 bullets/min. The battle set consists of 360 bullets. Other miscellaneous weaponry in tank consists of signal pistol, hand-grenade and personal weapons of the crew.

Stabilization of targeting line and bringing of gun into pre-defined position in space have been achieved by Fire Control System (SUP) which enables targeting of mobile targets day and night and under all weather conditions. SUP represents automatic electro-hydraulic system for stabilization in two planes enabling gun movement on height with the speed of 70 mrad/s on direction of 285 mrad/s with accuracy of 0.2 mrad/s. The key component of SUP is stabilized day and night targeting device with integrated daily channel, night channel with passive picture intensifier of the 2nd generation and laser distance measuring device up to 10000 m and accuracy of 10 m.

Ballistic computer process input data (target distance, meteorological-ballistic data, steering signals, initial speed, average targeting data, kind of ammunition and signals from giro block) calculating on the basis of these ballistic elements gun steering and firing command. Day and night commanding device contains night channel with picture intensifier of 2nd generation enabling tank commander acquisition of targets and priority control.

Antiballistic angles of multiple-layer configured front armor plate of the tank hull and powerful front part of the turret with silicate core provides high level protection against cumulative and kinetic projectiles. Additional anti-cumulative protection has been carried out by side armour plates on the hull and external equipment on turret. Compared with modern western tanks, tank M-84 has, due to its low profile, smaller front area, which makes him 15-20% smaller target. The level of anti-cumulative protection can be significantly increased by application of explosive reactive armour. For the purpose of camouflage during battle activities, tank M-84 uses Smoke Pots Launchers for creation of smoke curtain. Integrated system of crew protection consists of automatic fire extinguisher, system of nuclear-chemical and biological detection and devices for hermetically safe protection, filtration and ventilation of the cockpit of the tank.

Tanks of the family M-84 are driven by 12-cylinder, four stroke engine, multiple fuel, water cooled, turbo charged diesel motor, power 574 kW (780 HP) for M-84 variant or 735 kW (1000 HP) for variant M-84A and M-84AB. It has mechanical transmission with multiplication and two side reduction gears, 7 speed gears forward and one in reverse, with hydraulic steering, independent hangings with torsion shafts and hydraulic shock absorbers. With its specific power of 17.5 kW/t tank M-84A surmounts slopes up to 58%, side slopes up to 47%, vertical wall up to 0.85 m and trenches up to 2.8 m width. The water obstacles up to 1.8 m deep are crossed without preparation while deep fords up to 5 m require 20 minutes preparation time.

Intercom - device for mutual communication provides communication between crew members and external communication over receiver. Tanks M-84 and M-84A are equipped with conventional FM and UHF receivers with frequency range of 20-79.975 MHz and 20 km range. Tanks of the family M-84 are equipped with reconnaissance appliances, additional equipment for underwater drive, equipment for self digging, individual set of tools and appliances with possibility of attachment of mine sweeper.

The modification of the M-84 tank in 1994 resulted in the M-84K command tank; this version was equipped with different telecommunication systems, depending on its type, battalion or brigade one.

The beginning of this millennium brought the modified M-84 with increased fire power, maneuverability and ballistic protection.. The tank labelled M-2001 (M-84AB1) is as sophisticatied as the T-90S tank and it can compete with Abrams, Leclerc, Leopard, etc. When compared to the M-84, this tank has the easily exchangeable 125 mm gun barrel,(without turret removal) which, besides standard projectiles, fires laser-guided projectiles with the effective range extended from 2,500 m to 5,000 m. The M-2001 tank has a new system of dynamic protection installed into armor, a system of opto-electronic neutralization of STORA guided projectiles and a 1,200 hp power group. It is equipped with a number of new systems and devices that will make this tank very up-to-date in the decade to come.