Prithvi Air Defence (PAD) is an anti-ballistic missile developed to intercept incoming ballistic missiles outside atmosphere (Exoatmosphere). Based on the Prithvi missile, PAD is a two stage missile with a maximum interception altitude of 80 km. 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 system is being designed and developed at the missile complex in Hyderabad in southern India by engineers at three DRDO laboratories: the Defence Research and Development Laboratory, the Imarat research center and Advanced Systems Laboratory.All the parts of the system, except the main radar and the interceptor guidance packages, were developed in India, DRDO sources said.The system includes one radar system that tracks both the incoming missile and the outgoing interceptor, another 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, another DRDO scientist said.
When deployed, the PAD will include multiple radars and their control centers, interceptor batteries and their control centers, spread out over as much as 500 kilometers.The second phase will include more tests, and will include homegrown interceptors with ranges beyond 100 kilometers. It will end by 2012, when the system goes into operational service, Indian Air Force sources said.The interceptor rocket has 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.
India is developing a robust anti-missile defence system that will have high-speed interceptions for engaging ballistic missiles in the 5,000 km class and above. India has recently demonstrated the capability to handle such targets up to 2,000 to 2,500 km,
The missile carries sensors to guide it to its target.For exo-atmospheric intercepts, the system's main sensor is the Israeli Green Pine radar, which has a 600-kilometer range. India imported two Green Pines three years ago, one in operating condition and one as a kit that was subsequently assembled.The PAD has two intercept modes, each of which is designed to hit a target within four minutes: exo-atmospheric, or above 50 kilometers; and endo-atmospheric, or lower than about 30 kilometers. The first anti-missile defence system, which was successfully test-fired Dec 6, 2007 from the integrated test range in coastal Orissa, demonstrated the capability to intercept targets at 45 to 50 km (exo-atmospheric) as well as at 15 to 20 km (endo-atmosphoric) altitudes and disintegrating them.
The tracking and fire control radars were developed by state-run DRDO in collaboration with Israel and France. With the development and production being taken up concurrently, the Electronics and Radar Development Establishment (LRDE) in Bangalore has been commissioned to roll out more radars for short, medium and long range use in association with the private sector.'LRDE has a full-fledged facility at Kolar to assemble and calibrate the radars required by the defence forces.
For exo-atmospheric intercepts, the system's main sensor is the Israeli Green Pine radar, which has a 600-kilometer range. India imported two Green Pines three years ago, one in operating condition and one as a kit that was subsequently assembled. The lower intercepts are guided by a radar acquired from another country.
Baptised as the Prithvi Air Defence system, the agile interceptor has now been renamed as Pradyumna.DRDO needs to carry out at least three to four trials with both versions before the missile shield ready for operational use. "The test is likely to be conducted Chandipur off the Orissa coast. Phase I of this programme is slated to be completed by 2009, while it is to secure operational clearance by 2012-13.
DRDO says its missile system is comprable to the Israeli Arrow system and the American Patriot system, both of whose manufacturers are courting the Indian defence establishment for likely orders.DRDO expects ballistic missile shield to take care of threats from existing Chinese and Pakistani missiles.
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