Indian Ballistic Missile Defense (BMD) experiments progressed rapidly after the Defense Research and Development Organisation (DRDO) convinced the government on its ability to develop BMD technology in late 1999. India initiated the program in the light of Pakistan’s eschewing of a nuclear ‘no first use’ policy and heightened tensions during the Kargil war including a possibility of full scale nuclear war.
DRDO is developing a two-tier BMD system, capable of tracking and destroying incoming hostile missiles both inside (endo) and outside (exo) the earth’s atmosphere. DRDO’s BMD program has a two-tiered system consisting of two interceptor missiles, namely Prithvi Air Defense (PAD) for high altitude interception and Advanced Air Defense (AAD) for lower altitude interception. The PAD missiles are for intercepting ballistic missiles at altitudes between 50-80 km while the AAD missile is for destroying them at heights between 15-30 km.
The PAD is an anti-ballistic missile developed to intercept incoming ballistic missiles outside the atmosphere (Exo-atmosphere). Based on the Prithvi missile, PAD is a two stage missile the first stage is a liquid fuelled motor that uses two propellants and oxidizers while second stage is solid fuelled.
Work on the PAD began in 2000 with a planned $1 billion development budget. The work on design and development of the system was carried out at three DRDO laboratories: the Defense Research and Development Laboratory, the Imarat Research Center and the Advanced Systems Laboratory. All the parts of the system, except the main radar and the interceptor guidance packages, have been developed in India.
The system includes a radar system that tracks both the incoming missile and the outgoing interceptor, a radar system that helps classify the incoming weapon and sends data to the interceptor batteries, command- and-control computers, and a transmitter to help guide the interceptors. When deployed, the PAD will include multiple radars and their control centers, and interceptor batteries and their control centers, spread out over as much as 500 km.
India became the fourth country to have successfully developed an Anti-Ballistic missile system after United States, Russia and Israel when it successfully tested the BMD system for the first time on 27 November 2006. In the PAD missile test, an exo-atmospheric hypersonic interceptor missile was used to destroy an enemy Prithvi missile at an altitude of 40-50 km. Subsequently, on 06 December 2007, an endo- atmospheric interceptor took on an enemy missile at an altitude of 15 km.
Again on 06 March 2009, DRDO conducted a test of its interceptor missile and missile tracking radars for validating the advancements made in the Air Defense program. Modifications made in the interceptor missile PAD 02 provided it with higher energy, an improved guidance and control system and a Gimbaled Directional Warhead (GDW) with it. Though the interceptor missiles have been tested earlier, the main aim of the test was to validate the capabilities of the indigenously developed ‘Swordfish’ Long Range Tracking Radar (LRTR), a target acquisition and fire control radar for the BMD system. The GDW technology allows for a smaller warhead to destroy the target missile.
The PAD has two intercept modes, each of which is designed to hit a target within four minutes: exo-atmospheric, or above 50 km and endo atmospheric, or lower than about 30 km. The tracking and fire control radars were developed by state-run DRDO in collaboration with Israel t and France. With the development and production being taken up c concurrently, the Electronics and Radar Development Establishment s (LRDE) in Bangalore has been commissioned to roll out more radars for short, medium and long range use in association with the private sector.
For exo-atmospheric intercepts, the system’s main sensor is the Israeli Green Pine radar, which has a 600 km range. The lower intercepts are guided by a radar that was acquired from another country. Baptized as the Prithvi Air Defense (PAD) system, the agile interceptor has now been renamed as ‘Pradyumna’. Similarly, the of Advanced Air Defense (AAD) is being modified into a new surface-to- surface missile that could be possibly named as ‘Ashbin’. The Indian system is comparable to the Israeli Arrow system and the American p£ Patriot system.
In fact, the Indian BMD shield has bettered than the American PAC III system. AAD intercepts at much higher ranges and altitudes compared to PAC III as it has only 15 km range for BMD. For be ‘bridging technology gap’ and ‘accelerating technology development’, Russia, Israel and France provided assistance in areas where DRDO needed help. Russia helped India develop the new Radio Frequency Seeker for the interceptor, while Israel provided help in developing the ‘Swordfish’ and the French helped with the Fire Control System for the BMD.
DRDO expects the first phase of the system to be developed by 2011, resulting in the deployment of the BMD by 2015. For the phase two of the BMD program, hypersonic interceptor missiles will have to be developed to tackle missiles with a striking range of over 6,000 km. The second phase will include home-grown interceptors with ranges beyond 100 km. The test trials are expected to take place in 2011. The new missiles will be similar to the THAAD missile deployed by the USA and will require radars with scan capability of over 1500 km to successfully intercept the target.
The interceptor rocket will have a liquid-fueled first stage that uses two propellants and oxidizers, and a solid-fuel second stage with a gas thruster that can turn the rocket at more than five Gs. DRDO is also developing a robust anti-missile defense system that will have high-speed interceptions for engaging ballistic missiles in the 5,000 km class and above. Plans are also afoot to have space-based surveillance systems to ensure a hostile threat can be detected even earlier than the present LRTRs used in the BMD system.
When fully deployed, the two-tired BMD shield will be able to intercept any incoming missile launched at India from 5,000 km away. When a ballistic missile is launched at India, it will be detected using infrared sensors by early warning satellites. In 30 seconds, the initial trajectory of the missile would be tracked from space and information would be relayed to a missile defense command centre. Immediately, a point of interception would be calculated and the interceptor would be launched in 100-120 seconds. At the point of interception, the interceptor, travelling at a speed of Mach 4 and weighing 5.2 tonnes, would kill the hostile missile