How did Arjun, which took decades to develop, end up being such a disappointment? Here's What You Need to Remember: DRDO is busy at work designing Arjun Mk II, which will allegedly contain many improvements over the original Mk I. The Indian Army for its part is adamant it wants no part of the Mk II until prototypes perform satisfactorily, and would much rather buy an overseas tank. In the mid-1970s, India began development on a totally new, advanced main battle tank that would satisfy the needs of the country’s Armored Corps. An impressive combination of firepower, armor protection and mobility, the tank was to be India’s first indigenously produced tank—and one of the best in the world. The service date for the tank, known as Arjun, was confidently set for 1985.