The TR-85, actual Romanian MBT

The TR-85 is a third-generation main battle tank designed and built in Romania, based on the TR-77-580, and developed from 1978 to 1985, produced until 1990 and odernized since. This is perhaps one of the world's comprehensive upgrade of the venerable T-55. The last modernization program was initiated in March 1994 in order to upgrade the TR-85 to NATO standards, resulting in the TR-85M1 Bizonul ("Bison"), the apex of Romanian Land Forces. The TR-85M1 not only uses the same powerpack as in the Leopard 1 but had an improved turret with the "Ciclop" fire control system, improved armor and 100 mm BM-412 Sg APFSDS-T projectiles, plus a completely redesigned suspension, but reaching 50 tons, a far cry to its nimble ancestor.

Development: The TR-77-580

TR-77/580 (Romanian Museum) src pinterest, Kyle Moorer

The true ground for the development of the TR-85 is found in the TR-77 family developed from 1977. Itsefl resulted in the aftermath of the Warsaw Pact invasion of Czechoslovakia in 1969, in which Communist Romania adopted a new national defense doctrine based on self-sufficiency. In order to built a local defense industry by April 1968 the preliminary report about the tank production in Romania submitted to the National Defense Council cited improvements of the local T-55, which was available in numbers and well-known. It was ratified by Council on 13 October 1972 and quickstarted on 13 May 1974, with specifications written for the new medium tank, 40 tons with a 100 mm main gun, 500 hp.

Some 400 TR-580/TR-77 tanks were built based on the capabilities of the local arms industry, not from scratch but either not under license, for the T-55 tank. The initial batch of ten TR-77s (Tanc românesc model 1977), was to use the Leopard 1 engine, having its hull extended aft and a new set of six new roawheels.

The refusal of Germany to allow deliveries of the Krauss-Maffei powerplant to a Warsaw Pact member forced the development of the production vehicle called TR-77-580 (or TR-580) for "cu motor de 580 cp", a 580 hp engine variant. The latter was built by replocating the old T-55 V-55 engine, but revised for more power, on the same extended chassis. The TR-77-580 develoment started in 1974 and ran until 1980, production started a yeat before and ending 1985.

The TR-77 still kept from the original its night vision gunner's periscope, ammunitions, coaxial Machine-Gun and main guns sight, most of the turret and basic hull design, although modified, including the same engine at first. The interior layout however was quite different.

Genesis of the TR-85

From 1974 Romanian engineers had been working in a reverse engineered version of the MTU Leopard 1 engine and transmission, eventually delivered via secondary sources. But it eventually stopped as engineers still lacked the experience for that complex 800 hp design and in 1976 Institutul Național de Motoare Termice came forward by stating it could design a derivative of the Leopard 1 diesel engine using local technology and solutions.

ICSITEM research institute (Bucharest) also announced it was able to create the hydromechanic transmission based on an exiting model, manufactured by Hidromecanica Brașov factory. Both engine and transmission were designed between 1974 and 1982 so 12 years, using foreign technology whenever possible. According to General Ion Mihai Pacepa, Romanian spies provided the engine technology with some confidential assistance from the Federal Republic of Germany.

This work resulted in the TR-85-800 (Tanc Românesc model 1985 cu motor de 800cp). Designed went on from 1978 to 1986, and in addition to the 830 horsepower powerpack and new suspension, the turret only shared its frontal part to the original. The rear is elongated. Later the whole rear part was cutout and fitted with a very long pannier for extra ammunition and better separation from the crew.

Design of the TR-85

The most striking aspects of the new design, were a longer hull, with apparenly a better sloped nose, due to the longer drivetrain with six roadwheels either sides, and long rear engine compartment, making for a much longer chassis overall, while due to the smaller diameter main roadwheels, the tank is also lower, presenting a smaller target. The turret is however the most striking aspect, it was about the same as the TR-77 for the early series, but was radically upgraded with a rear pannier at the end of the production.

Typical tank layout is used with the front driver's compartment unchanged and fighting compartment in the center (turret), engine compartment in the rear as in the T-55. The driver's hatch is located on the front left and the commander is seated on the left side, the gunner to his front, the loader seated on the right.

Like the T-55, this is a cramped TR-85 crew compartment, especially compared to NATO standards. The extended chassis only allows the extra space to fit a larger engine. The TR-85M1's turret bustle is its main feature, but houses additional equipment only. The Romanian army still recommended a maximum height for tankers of 1.68m.

Powerplant

The TR-85 originally had the new home-grown 830 horsepower 8VS-A2T2 engine, which is a 4 stroke, 8-cylinder, liquid-cooled turbo charged unit with direct injection. It is a diesel engine connected to a six speed (four forward, two reverse) THM-5800 hydromechanic transmission. The latter engage under load, with one power flow in straight run, two power flows in turns, and planetary final transmission. Governed top speed is 50 km/h on flat.

Maximum road range is about 400 km on cruise speed and flat. It could be haved off-road. However, outside the inner duesl tank, two more 200-liter drum-type can be fitted at the rear, for an increased operational range or around 650-700 km. The TR-85 kept the trademark T-55 unditching beam aft, and it procured a snorkel to allow river crossings mounted at the rear of the hull also. The new FCS and equipment asked for the addition of a Kollmorgen generating set providing 20 kW of stable voltage.

The TR-85 tanks uses a twelve roadhweel (six per side, with four aft and two further apart forward), resting on modern torsion bar suspension. This running gear made of dual rubber-tyred road wheels also comprised four return rollers per side, with the idler wheel at the front, drive sprocket at the rear. The two bolt tracks had metal-rubber articulations.

The TR-85 is able to cross a trench of 2.8 m and a vertical object of 0.9 m. It could manage a Gradient of 60%, a side slope of 40%, and Ford 1.4 m without preparation. It could cross deeper rivers with preparations, using its snorkel. The TR-85 lacks the left hull side exhaust outlet of previous versions, and also the oil sprinkler allowing to produce a large smoke cloud for active protection.

Protection

TR-85 is given for 55-ton and for 32.7 feet long, 11.3 feet wide 10 feet high has a generally more dicreet profile than the T-55, but its crewed the same: Driver in the front-left hull, commander, gunner, loader in the turret. Classic Armor protection relied on a 320mm thickness at the turret face, and 200mm on the hull (increased by the sloping). 20mm addon armor at the nose is fitted to received add-on Explosive Reactive Armor (ERA) blocks.

Armament

Main

-100 mm A308 rifled tank gun. It is a locally manufactured adaptation of the old M1977 towed anti-tank gun, made by Arsenal Reșița, shared by the TR-77. Rate of fire is circa 4-7 rounds per minute. In all, 41 ronds are carried between the hull floor, hull sides and turret sides (ready rounds). The gun barrel is still fitted with the same bore evacuator and thermal sleeve as the standard TR-77. It is manually loaded.

Ammunitions includes the following:

• APFSDS-T (BM-421 Sg), kinetic penetrator.
• Shaped Charge (BK-412R and BK-5M)
• High Explosive (OF-412)
• Armour Piercing with tracer (BR-412B/BR-412D)
• Target Practice (PBR-412, PBR-421B)

The BM-421 Sg round (M309 cartridge) was developed with Israel as part of the modernization started in 1996, manufactured by Aeroteh SA (Bucharest), marketed by ROMARM SA. Compatible with standard T-55 100 mm guns, it could penetrate up to 444 mm of RHA inclined at 90° at 500 meters, 425 mm/1000 meters, 328 mm/4000 meters.

Roof HMG

12.7×108mm (0.5 cal.) DShKM heavy machine gun, on the loader's hatch ring pintle mount. It is made in Romania, at UM Cugir and is procured tracers for antiaircraft fire. The gunner has to partially expose himself, which is a liability in 2000s standards

Coaxial LMG

7.62×54mmR PKM machine gun (by UM Cugir, sub-version for tanks of the md. 66 machine gun). Fitted in a coaxial mount, right of the main gun. It is aimed and fired using the Ciclop fire control system aans also uses tracers to allow fire aiming in case the laser rangefinder would be destroyed.

Sub-systems

The main gun uses the second generation FCS Ciclop, equipped with an Intel 8080 microprocessor of 1 ko of RAM, 12 ko of system memory.

TR-85 Production

The main tank factory was established by decree nr.514 in December 1978 at FMGS division (Fabrica De Mașini Grele Speciale), 23 August plant (now FAUR), Bucharest, completed in 1980. The factory is a top secret military zeone requiring special accreditation to enter. In 1983, the FMGS factory was able to deliver 210 tanks yearly, not a small feat for any warsaw pact country. The TR-85 was delivered from 1986, and until 1990 at rate of 100 tanks yearly with three years of rooling swap from the TR-77 to the TR-85.

The new engine however proved mechanically unreliable as revealed by early state tests and teething problems with high fuel and oil consumption, transmission issues, oil leakages delayed the entry into service. The bitious, locally designed Ciclop fire control system was plagued by poor quality electronics. The laser rangefinder never saw its intended daylight aiming system. Limited corrections only could input the ballistic fire-control computer.

As Nicolae Ceaușescu decided to cancel in July 1982 all imports of special equipment for the arms industry to boost local industry, even threatening to stop tank production because of the poor manufacturing records, situation only worsened and the initial teething problems were had to wait for after the revolution and assitance from the west, as well as importing foreign parts.

Known variants

TR-800 at King Ferdinand Museum (photo: Stan Lucian)

TR-580: TR-85 preserie with similar hull, six spoked road wheels, different skirts fitted.
TR-85: An upgraded T-55 with minor changes.
TR-85N: upgraded TR-85.
TM-800: Upgraded TR-85 with new engine and roadwheels among others.
TER-800: Armored Recovery Vehicle, based on the TM-800 chassis.
TR-85M1 Bizonul: See later. Latest upgrade.
TR-125: A locally modified T-72 using some elements of the TR-85M1
DMT-85M1: Combat Engineering Vehicle (CEV) based on the TR-85M1 chassis
TR-85M2: Prototype MBT with a 1,200 hp IVECO diesel tested in 2002.





Minehunter vehicle based on the TR-85M1 chassis

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The TR-85M1 Bizonul

In March 1994, the Romanian General Staff now could purchase military equipments from the west, and it was compounded by the entry into NATO in 2004, leading to a further upgrade of the M1. The TR-85M1 was produced from 1999 into 2009.

The initial modernization program came from the order no. 1429, On 14 April 1994. It was approved by the Supreme Council of National Defense, development officially under the designation TR-85M1 Bizonul (The Bison), started in 1996. Two prototypes were built, into order to improve the TR-85 to NATO standards (as request by the North Atlantic Treaty Organization to join). These standards imposed to revise and improved firepower, protection and mobility, as the communication systems and engine and transmission, braking system reliability.

The modernization program soon called several company, mostly from France: Aerospatiale Matra, Sagem, Kollmorgen-Artus, Racal. The main project was under responsability of the new ROMARM military consortium, but also METRA (Military Equipment and Technologies Research Agency), Electromagnetica, FAUR, Elprof, Aeroteh, IOR, Prooptica, Artego, Arsenal Reșița, Metav, Forsev, Anticorozivul, IEMI, Rolast, Aerostar and IOEL. The M1 as the result, became compliant with NATO standards, helping integration in 2004.

The TR-85M1 "Bison" remains the standard Main Battle Tank of the modern Romanian Army but is available in limited numbers compared to the TR-85.

Armament

TR-85 M1 12.7mm DShK and CICLOPS M FCS at BSDA in 2007

It ises the same 100mm A308 rifled main gun, based on the M1977 anti-tank artillery system, but made compatuble with 41 NATO-standard projectiles. It kept the same fume extractor near the muzzle as the original. Thanks to its FCS it can engage targets beyong 1000 meters with Armor-Piercing, Fin-Stabilized, Discarding Sabot (APFSDS) able to defeat 45 cm RHA equivalent. Secondary armament are the same coaxial 7.62mm PKT and roof-mounted 12.7mm DShK for AA defense.

Protection

Smoke and flare dischargers are found along the turret sides and figure prominently into the defense of vehicle and crew. The turret is well-sloped and the tank maintains the low-profile approach of the T-55 in keeping with Soviet tank design doctrine of the Cold War. The modernized TR-85 features a indigenous fire control system (FCS) as well as infrared night vision, a laser rangefinder for accuracy and a laser warning receiver.

Powerplant

The TR-85M1 uses an improved engine 8VS-A2T2M rated for 860 horsepower, for a top speed of 60 km/h on flat. The weight jumps to 50 tons, lowring in effect the power-to-weight ratio from 19.7 to 17.2 hp/tonne. The M1 also replaced the ancient suspension by eight telescopic hydro-gas shock-absorbers, in order to increase the overall speed. The M1 tracks uses aluminum alloy road wheels and its braking system is brand new, replacing the old wet multi-disc brakes with dry multi-disc brakes. The hydraulic system has been upgraded with new servomechanisms as well.

FCS and subsystems

TR85M1 of the 631st Tank Battalion live firing

The M1 is give the 3rd gen Ciclop-M ballistic fire-control computer, also laser-guided, with the inputs automatically converted in real time as actionable targeting data. It is alleged to procure 95% first shot capability, under 2000 meters and still circa 75% until 3000 meters. The Ciclop-M allowed to hit also in indirect fire a target 6000 meters away with the OF-421 high explosive round or below that, the BM-421 Sg APFSDS-T round (5 km) and at 4 km the AP-T round. The HEAT are only efficient up to 3,000 m. The coaxial machine gun range is also improved using the same FCS, up to 2,000 m.

The gun is electrically stabilized (2 axes) using the French EADS computer, improving accuracy, reducing target engagement time. Data considered for the solution comprises the turret temperature, noise, fire hazard and maintenance. The turret keeps its original RKS roller bearings. The gunner's day sight telescopic periscope integrates a laser rangefinder ranging from 200 m to 5.000 m, plus electronic reticle.

The new laser designated above the gun mantlet is a SAGEM MATIS thermal viewer operating at wavelengths between 3 and 5 μm, in the spectral band. It replaced the original M1 SAGEM ALIS thermal viewer and is now locked for export. The driver's AONP-I passive night sight is the standard, original night vision device. The commander uses the new SFIM EC2−55R panoramic sight, with 2nd gen. SAGEM image intensification system independently directed for a hunter-killer configuration. The communication system comprises HF and UHF transceivers, fitted with intelligent frequency hopping and encryption. There is also an intercom with 4+1 stations.

Deployments

TR-85 in the Romanian Revolution, December 1989

TR-85 tanks were used in security roles during the 1989 Romanian Revolution, seen during demonstrations across several Warsaw Pact entities before 1991. The revolution (16-27 December) saw these crews, reluctant to fire on the crowds, effectively taking part in the revolution.

As of 2013, the TR-85 is only used by Romanian Army and has never been exported. 250 early TR-85 are still in service, and 54 TR-85M1 Bizonul.


TR-85 of the 631st Tank Batallion in early 1990, in the streets of Bucarest

Links and sources

TR-85 in training, 1990s

On wikipedia (in Romanian).
On Rumaniamilitary.ro
globalsecurity.org
militaryfactory.com
military-today.com/tanks/tm_800
military-today.com/tanks/tr85m1
army-technology.com
On armyrecognition.com
On forum.warthunder.com

Specs. TR-85
Dimensions (L-w-h):	9,96 x 3,43 x 3.1 (32.7 x 11.27 x 10.2 fts)
Total weight, battle ready :	50 Long Tonnes (55.12 short tons)
Crew :	4 (driver, commander, gunner, loader)
Propulsion :	8VS-A2T2M C.N. 8-cyl., TC DI diesel 860 hp (640 kW)/2300 rpm
Max speed (on/off road):	60 kph (37 mph)
Range (road/bad road) - Fuel:	400km (250 mi)
Armament :	Main : 100 mm A308 50 rds Sec. 12.7 mm AA - 7.92 coaxial LMG: 500 & 3500 rds.
Armour :	Composite armor, turret 320+20 mm, hull 200 mm (see notes)
Total production	617

Gallery :

The TR-77 in the 1980s, for comparison


TR-77 testing the TR-85M turret bustle


Camouflaged TR-85 in the 1990s.


TM-800. It uses the same fully-stabilized 100-mm rifled gun as the regulat TR-77 and T-55, but locally produced in Romania, loaded manually. It has a ballistic computer and laser rangefinder, coaxial 7.62-mm machine gun, roof mounted 12.7-mm KPT heavy machine gun. Hull and turret incorporates composite armor (frontal arc), NBC, automatic fire suppression systems, and smoke dischargers but no ERA. The crew is unchanged (commander, gunner, loader and driver). But the TR-800 has six new small road wheels per side and side skirts. Its diesel engine developsg 830 horsepower.


TR-85M of the preserie in green livery, testing, 1995


Current TR85M1 Bizonul

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The Ukrainian T-55AGM is equipped with a 105mm modern gun, using modern ammo, making it superior to the old ammo ordnance of the TR-85M1.