NEW DELHI: India has got one step closer to deploying a new missile shield over its Capital, with US state department notifying its Congress of the impending sale of an integrated air defence weapon system ( IADWS ) to New Delhi for $1.86 billion.TOI in July 2018 had first reported that India was moving swiftly ahead to acquire the IADWS or the National Advanced Surface to Air Missile System-II ( NASAMS-II ) from the US, which will be used along with indigenous, Russian and Israeli systems to erect an ambitious multi-layered missile shield over the National Capital Territory of Delhi against aerial threats ranging from drones to ballistic missiles.India and the US have already held several rounds of negotiations, including selection of sites for deployment of the missile batteries around Delhi, for the proposed sale under the American foreign military sales (FMS) programme, as was reported earlier by TOI.Once the deal is inked, the NASAMS-II deliveries will take place in two to four years, say sources. Though the US was also mounting pressure on India to also consider its Terminal High Altitude Area Defense (THAAD) and Patriot Advanced Capability (PAC-3) missile defence systems, New Delhi went ahead to ink the $5.43 billion (almost Rs 40,000 crore) deal with Russia for five squadrons of the advanced S-400 Triumf surface-to-air missile systems in October 2018.As per the proposed overall air defence plan for Delhi, the innermost layer of protection will be through the NASAMS. It will be a combination of different weapons like Stinger surface-to-air missiles, gun systems and AIM-120C-7 AMRAAMs (advanced medium-range air-to-air missiles), backed by three-dimensional Sentinel radars, fire-distribution centers and command-and-control units. “The networked system, capable of even shooting around buildings, will take care of 9/11-like and other close-in threats,” said the source.The outermost layer of Delhi’s missile shield, in turn, will be provided by the indigenous two-tier ballistic missile defence (BMD) system being developed by DRDO. This system’s AAD (advanced air defence) and PAD (Prithvi air defence) interceptor missiles are currently geared to intercept enemy missiles, in the 2,000-km class, at altitudes from 15-25 km and 80-100 km respectively.The second layer will be through the highly automated and mobile S-400 systems, which will have missiles with interception ranges of 120, 200, 250 and 380 kms, backed by their associated battle-management system of command posts and launchers, long-range acquisition and engagement radars.Then will come the Barak-8 medium-range surface-to-air missile systems, jointly developed by Israeli Aerospace Industries and DRDO, which have a 70-100 km interception range. The indigenous Akash area defence missile systems, with a 25-km range, in turn, will form the layer over the NASAMs.