The debate around a third aircraft essentially arises from the monumental cost outlay required to build one. India's INS Vikramaditya aircraft carrier. | Photo Credit: PTI Key Highlights The third aircraft carrier, INS Vishal, still to be approved, may cost up to $8 billion and is likely to take 14 years to build Some, including officers from the Navy itself, have contended that the naval defence budget may be better spent in modernising India's submarine fleet In recent years, the Indian Navy has also been the victim of falling budgets A third aircraft carrier is an “operational necessity” said Navy Chief Admiral Karmabir Singh reviving the discussion within India's defence establishment over whether the in-operation INS Vikramaditya and the INS Vikrant (currently undergoing sea trials) needs a partner to expand the Navy's force projection in the Indian Ocean. The Navy chief's words are a reiteration of a similar call he made earlier this month on Navy Day when he said, “air power at sea is absolutely required.”