Tank-Ex/MBT-EX is the code name to a new tank developed by the Indian Defence Research and Development Organisation (DRDO) in 2002. It is rumored to be called "Karna", after one of the heroes of the Indian epic 'The Mahabharata'.
The Tank-Ex/MBT-EX is a new prototype tank developed for the Indian Army by the Defence Research and Development Organisation (DRDO) in 2002. This tank has been developed by integrating a modified low silhouette chassis of in-service T-72 tank and a re-engineered Arjun MBT turret. The Tank-EX is intended to provide a solution for upgrading the Indian Army's aging T-72M1 fleet. Tank EX is more of a hybrid between the Arjun tank and the T-72M1, with armor and firepower characteristics used from both models. According to sources at the DRDO at least 2 prototypes have been built, and improvements are being made constantly.
After the trials are over as many as 300 tanks may be ordered from the DRDO in the future and further T-72 hulls may be imported from Russia instead of utilizing the existing ones.
Director general of Indian mechanised infantry Gen. Dalip Bhardwaj said on 5 July 2008 that the army had rejected Tank-EX. This was part of an announcement that there would be no further orders for Arjun tanks, and the army would be inviting participants from various countries to discuss future tank developments.
The Tank Ex at 47 tons is heavier than the T-72M1 (41 tons) and much lighter than the Arjun MBT, which tips the scales at 58.5 tons.The Tank-Ex has a power plant (like on the Combat Improved Ajeya) giving a power to weight ratio of /ton for a weight of 47 tons. This represents an improvement over the T-72M1's /ton with a weight of 41 tons and a power plant. The Tank Ex utilizes the Arjun MBT's 120 mm rifled gun firing unitary APFSDS and HESH semi combustible cartridge case ammunition. A total of 32 rounds are carried as compared to 39 in the Arjun and 45 two piece ones in the T-72. The choice of caliber, weapon design and ammunition allegedly make it superior to the in-service 125 mm 2A46 guns on the T-72M1. A global positioning system is provided for accurate navigation. This is a feature common to both the Arjun MBT as well as the Combat Improved Ajeya. The Tank Ex utilizes the "Kanchan" composite armor especially over its frontal arc (turret as well as glacis) giving it protection against both Kinetic and HEAT rounds. The usage of the Arjun turret design indicates that the Tank-Ex may also have its "ready" ammunition stored in the bustle (as in the Arjun), separated from the crew and provided with blow off panels. This would be a significant protective feature in line with western design practices. The Tank Ex retains the T-72's mobility, with a road speed of 60 km/h and a cross-country speed of 40 km/h. With a maximum gradient climb at 30 degrees it remains in line with all variants of the T-72 like the T-72BM. The Tank Ex is better at trench crossing: 2.6 meters as compared to the T-72M1's 2.28 meters. Vertical Obstacles 0.85 metres tall can be surmounted. Shallow fording is quoted as 1.2 metres. The Tank EX should also have the possibility to fire the Israeli LAHAT missile from its gun-barrel, like the Arjun.