Arjun
At the end of the 1971 war, the Indian army realized the limitations of their tank fleet in the harsh desert conditions of Rajasthan, a northwestern Indian state bordering Pakistan, so they initiated their own MBT design. The Main Battle Tank (MBT) occupies a pivotal role in the present day battle field on account of its ability to provide accurate fire power with cross country mobility, reasonable protection from conventional and nuclear threats and flexible response to changing battle situations.
In order to eliminate dependence on foreign countries for design and manufacture of Armored Fighting Vehicles (AFV) and to place the country on par with super powers with regard to quality of tanks and also to eliminate completely the requirement of foreign exchange (FE) in the production of tanks, Government in May 1974 sanctioned a project for design and development of MBT by Defence Research and Development Organisation (DRDO) at a total cost of Rs 15.50 crore (FE Rs 3.70 crore). The tanks were to be in service during 1985 to 2000 AD and were in replacement of existing tanks which were expected to be out-dated beyond 1985.
- The original requirement was for a 40-ton tank armed with a 105mm gun, and DRDO had to start from scratch. Midway through this process, the Army changed its requirement to a 120mm gun armed heavier tank, capable of going toe-to-toe with the American Abrams tank, which Pakistan, was thought to be about to acquire from the United States in the 1980s.
- The army thinks that the Arjun tank is cumbersome for strategic movement, i.e. to be taken from one sector to another. It is too wide and too heavy to be moved in the railway carriages in India.
- When projects, like MBT were taken up in early 80s, Indian Industry was just not ready to embark on these types of products and DRDO decided to initiate development including major components/sub-systems in-house. The delays in development of weapon systems MBT Arjun, not only has caused significant loss of revenue but also delayed the timely procurement of weapon systems from foreign sources that were needed to keep the forces fighting fit and modernized. The delays cause suspicion on the capability of DRDO in the eyes of the users, the common man and intelligentsia.
- Even after the lapse of more than 32 years, the nominated agency of DRDO could not execute the mission so far. Inordinate delay has escalated the original cost of MBT project from Rs.15.50 crore in 1974 to Rs.306 crore in 2005. Neither the execution agency of DRDO or the certifying agency Director General Quality Assurance (DGQA) took responsibility for the inordinate delay and quantity in production of MBT Arjun.
- The Arjun costs Rs.168 million while the T-90 costs around Rs.120 million. But the Arjun compares favorably with western MBTs of its class that cost Rs.170 to 240 million.
- The case of the Main Battle Tank (MBT) illustrated the disadvantage of not having a consortium with the user as an active member. The MBT (“Arjun”) project, which did not take the concurrent engineering route, took five long years in user trial, although there were no major changes in design. As many as 17 Tanks were put to near-destructive tests during this long phase of user trial. The long time taken in trials also led to considerable escalation in the product cost.
- The Arjun project was entirely financed by DRDO. The absence of physical and financial commitment on the part of the user was a contributing factor to the time and cost overrun experienced in this project. In its meeting held on 26.3.1974 the Cabinet Committee on Political Affairs approved project for design and development of Main Battle Tank with an outlay of Rs. 15.50 crores. The same was enhanced to Rs.305.60 crores due to changes in the General Staff Qualitative Requirements and cost escalations caused by inflation.
Arjun Design
The first “Arjun” (named after a mythical Hindu warrior prince) concept was laid out in 1974 by the Combat Vehicles Research and Development Establishment (CVRDE) of the Defence Research and Development Organization (DRDO). Based on 1971 battlefield experiences, the Arjun would have a locally-designed, rifled 120mm main gun, a German, MTU-based diesel powerplant (The Indians consider turbine engines fuel guzzlers), and a computerized fire control system with a laser rangefinder.
The superior armor defeating capability of the indigenously developed Fin Stabilised Armour Piercing Discarding Sabot ammunition and 120 mm caliber rifled gun give MBT Arjun an edge over contemporary world tanks. A computer-controlled integrated fire control system incorporating day-cum-night stabilised sighting system guarantees a very high first round hit probability and reduced reaction time to bring effective fire on targets. All round protection from anti-tank ammunition is achieved by the newly developed Kanchan armour to a degree much higher than available in present generation tanks. The Arjun was to be the mainstay of the Indian Army.
Considered comparable to the M1A2 Abrams, Leopard 2, and Leclerc, the 59-ton "15th Variant" can achieve a maximum speed of 70 kph (55 mph) and cross-country speed of 40 kph with its 1400-hp powerplant. The 1,610-liter fuel tank allows for a cruising range of 200 km (120 miles). To ensure crew survivability, production versions will have the indigenously-researched and developed ‘Kanchan’ composite armor, an automatic fire detection and suppression system, and an NBC protection system designed and built by the Bhabha Atomic Research Center.
The rifled 120mm gun, which includes a muzzle reference system, is made of ESR steel and is fitted with a thermal sleeve and fume extractor. All main gun rounds use a semi-combustible cartridge case with increased energy propellant for higher muzzle velocity and greater penetration characteristics. In addition to the usual suite of rounds, an anti-helicopter round is under development as well. The Arjun’s fire control system includes a laser rangefinder, ballistic computer, thermal imaging night sight, stabilized panoramic sight for the tank commander, and a secondary telescopic sight. The LRF (integral to the gunner’s sight) has a range of nearly 10 km and a thermal imager (which can “see”’ at around 5.5 km, recognize a target at 3.1 km and identify targets at 2.5 km). The Arjun fire control system’s ability to fire on the move during the night is a major step forward for Indian armored forces.
The Chassis and Automative System of MBT Arjun comprises main chassis, power pack (1400 HP engine coupled to hydromech transmission), running gear with hydropneumatic suspension, integrated fuel system, advanced electrical system and other dedicated special systems like integrated fire detection and suppression system. The chassis is fabricated from rolled homogenous armour plate using advanced welding technique. Frontal armour is of Kanchan composite sandwitched between armour plates. This fully integrated Arjun chassis and Automative System having smooth riding characteristics can be used as a mobile platform for any advanced weapon system. An extremely effective hydropneumatic suspension system has been developed for MBT Arjun. The suspension is externally mounted and provides vehicle springing and damping. It consists of one bogey wheel pair for each suspension station. Gaseous medium in the hydropneumatic suspension is for all terrain maneuverability for exploiting the power available. Casing and hub of the hydropneumatic suspension are sealed for preventing dust ingression and water seepage into the casing during operation in marshy area or shallow/medium fording. The MBT Arjun is fitted with double-pin steel track with detachable rubber pads. It is made out of steel casting having two bores for insertion of rubberised pins. It is an integral piece incorporating guide horns and has got a provision for insertion of detachable pads. The end connectors are induction-hardened in the area which comes in contact with the sprocket teeth to prevent wear.
The integrated fire and explosion suppression system developed for MBT Arjun is based on state-of-the-art technology. The indigenous development of this system is considered to be a breakthrough in the field of fire protection engineering. It is capable of suppressing hydrocarbon fuel fire/explosion resulting from an enemy hit on the tank or due to any malfunctioning of the engine, transmission or any electrical short circuiting. The system is based on infra-red detectors for the detection of fire/explosion in the crew compartment of the battle tank and a continuous type of linear thermal detector popularly known as fire-wire for the engine compartment. Halon-1301 has been employed as a fire extinguishing medium. The system is capable of detection and suppression of hydrocarbon fuel fire/explosion in the crew compartment within 200 milliseconds and in the engine compartment within 15 s thereby enhancing the chances of survivability of the crew and battle effectiveness of the tank.
Arjun Variants
Planned Arjun variants include mobile assault guns, an observation post vehicle, an air defense (gun or missile) version, a recovery vehicle, an engineer vehicle, and bridgelayers. New bridge-layers and recovery vehicles were necessary, given the Arjun’s substantial weight increase over the T-72M1 series.
