India’s quest to build its own main battle tank has been one of determination, disappointment, and slow progress. For most of its early post-independence years, the Indian Army relied on imported tanks—Soviet T-72s and T-90s and British-designed Vijayanta. The 1971 war experience and a growing desire for defense indigenization provided the context for a homegrown answer: the Arjun MBT.
The project was initiated during the late 1970s when the Combat Vehicles Research and Development Establishment (CVRDE) was tasked with designing a tank from scratch. Cooperation with Germany’s Krauss-Maffei, manufacturer of the Leopard 2, in 1983 provided the necessary expertise. A prototype had been built by 1989, which looked like the Leopard 2A4, but significant obstacles still existed.
Early tests were not without drama. Engines would overheat, transmissions would buckle, and metallurgical flaws would affect durability. The 120mm rifled gun, an indigenous development from the Armament Research and Development Establishment (ARDE), could not fire standard NATO ammunition, causing logistics and supplies problems.
The German MTU 1,400 HP diesel engine, powerful though it was, did not exist in other nations, so support would be a problem. Crew ergonomics and the fire-control system also had to be modified to meet operational requirements.
Despite these setbacks, the Arjun Mk1 began production in 2003, and 124 tanks were delivered. Its unique Kanchan composite armor, developed by the Defence Metallurgical Research Laboratory (DMRL), could withstand advanced anti-tank ammunition, such as APFSDS. The tank also had NBC (nuclear, biological, chemical) protection, auto-fire suppression, and the integration of passive and active defence systems, which provided it with good survivability.
The Mk1A was a significant upgrade. Israeli experts assisted in ironing out any remaining faults in 2007. The tank underwent about 100 upgrades during the next two years: ERA/NERA module-strengthened armor, an improved suspension, a new turret, advanced fire control, safer ammunition storage, and a remote gun. A soft-kill active protection system was added to enhance protection against existing threats.
These enhancements came at a cost. Mk1A put on weight to 67 tons, reducing its top speed to just 55–58 km/h. Yet, its firepower did not diminish. The 120mm rifled gun could now fire Indian-produced APFSDS and HESH ammunition, besides gun-fired ATGMs like the native SAMHO missile, in place of the erstwhile Israeli LAHAT.
One of India’s biggest hurdles for its armored forces has been reliance on foreign engines. With MTU halting production, looming shortages in supplies threatened. In response, DRDO and BEML designed the DATRAN 1500 HP turbo-charged diesel engine that can operate in harsh climates and at altitudes of 5,000 meters. It has CRDi fuel injection, self-cleaning filters, and greater ruggedness.
The new engine requires the widespread modification of the Arjun engine bay, as its configuration is different from the MTU. The retrofit will take a couple of years or more, with widespread trials thereafter before full operational deployment, not only for the Arjun but also for future programs like the Future Ready Combat Vehicle (FRCV).
The Arjun Mk1 reportedly surpassed the T-90 in tests in accuracy, subsystem reliability, and overall performance. Bharat Electronics Limited’s (BEL) fire-control system is also being integrated into India’s licensed T-90s. The Arjun of today is mainly deployed on the western front, with the 43rd Armoured Regiment using it for parades and exercises. The Mk1A, advanced with AI-targeting and greater mobility, is the height of India’s indigenous armored prowess.
In the coming years, the FRCV program will replace more than 1,500 ageing T-72s with a modular, AI-compatible platform that can take NATO-standard ammunition. DRDO is also producing a new 120mm smoothbore gun to cut down on logistics. Foreign help remains on the cards; Russia has offered the T-14 Armata for India’s future MBT program, and this could be combined with domestic manufacture and the DATRAN engine. Geopolitical and technical factors, including sanctions, must continue to be balanced.
The Arjun’s story has been a protracted one, a difficult one, and not uncommonly a politically contentious one. Each milestone—from the trials of Kanchan armor to the construction of the DATRAN engine—signals India’s growing independence in armored warfare. Whether the Mk1A is a ubiquitous frontline tank or a bridgehead for next-generation systems, its legacy is clear: it is India’s resolve to develop indigenous capability and strength in modern armored warfare.