New Delhi: Six years after the Arjun tank fleet was first due for overhaul, the Army has finally initiated the process, beginning with two MK-1 tanks at the Heavy Vehicles Factory in Avadi near Chennai, according to media reports. These tanks will be stripped down and rebuilt, marking the first full overhaul since the platform’s induction in 2004.
The pilot project will see the two tanks fitted with 26 upgrades derived from the newer MK-1A variant. Defence sources confirmed that repair procedures and assembly process sheets developed during this exercise will serve as templates for the overhaul of the remaining 124 tanks in service.
The Comptroller and Auditor General had flagged in 2016 that the Arjun was due for its first overhaul in 2020, but no agency had been identified to carry it out. The same audit revealed that the tank had not been operational since 2013 due to inadequate spares and the absence of repair facilities, with HVF unable to meet requirements.
Engine-level work had been attempted in the interim. Engine Factory Avadi and DRDO’s Combat Vehicles Research and Development Establishment had already conducted an overhaul of the Arjun powerpack, which has informed the current scope of work. However, a full tank rebuild, involving stripping the hull and turret, had not been undertaken until now.
Much of the technical documentation required for the overhaul is still missing. Repair procedures will be developed based on the condition of individual components as the tanks are dismantled. Of the 26 upgrades, six are major improvements. These include a commander’s panoramic sight, MK-2 gunner’s main sight, automatic target tracker, improved muzzle reference system, new tracks with increased horn height, and an advanced running gear system.
The 20 minor upgrades range from a compact high-power auxiliary power unit and improved fire detection and suppression system to LED headlamps, enhanced dust sealing, and heating elements in periscopes.
Once dismantled, assemblies will be sent to specialised facilities: the engine to engine Factory Avadi, transmission and final drive to RENK’s Indian arm, the 120mm gun and cradle to Advanced Weapons and Equipment India, and the gun control system to Bosch Rexroth in Germany.
Several components, including gyros, batteries, tracks, panoramic sights and fire detection systems, will be sourced from Indian companies. The Arjun has faced persistent availability issues due to its high imported content.
A 2017 CAG report noted that 69% of the MK-1 was imported at induction, with suppliers spread across Germany, Belgium, France, Israel and the UK, many of whom have since exited the market. The report also criticised DRDO’s CVRDE for failing to indigenise critical components and HVF for not supplying spares, which undermined operational readiness. The Arjun is powered by a 1,400 hp MTU engine from Germany coupled with a RENK transmission. Its powerpack is rated for 600 hours or 5,000 km before overhaul is required.
The tank’s bulk has posed logistical challenges. Transporting it requires dedicated broad-gauge rail stock or specially configured road transporters, both costly and scarce. The 2017 audit calculated that moving a regiment of 60 Arjuns required 16 additional three-ton vehicles and at least 50 extra personnel.
Following rebuild, the two tanks will undergo hull and turret stand tests, stability proofing, running trials, and limited validation trials at the Pokhran range. The overhaul will carry a warranty of 24 months or 150 engine hours, whichever comes first.
Meanwhile, the 118 Arjun Mk-1A tanks ordered in September 2021 for ₹7,523 crore are yet to be delivered, with engine supply delays cited as the main bottleneck. The existing fleet of 124 MK-1s, inducted between 2004 and 2010, equips two armoured regiments, the 43rd and 75th, deployed in Rajasthan’s desert terrain.
The overhaul of the Arjun tanks thus coincides with broader efforts to strengthen resilience, both in defence preparedness and civil disaster management, underscoring the importance of long-term planning and coordination across sectors.
