From Missile thread:
tejas wrote:Perhaps Arun garu can clarify this for me but I am at a loss to see the advantage of having a liquid fuel interceptor ( PAD) rather than a solid fuel one (AAD, PAC-3, THAAD, S300, Arrow2). With the Prithvi production line being shut down what gives?
Grasshopper awaits enlightenment from the master

BTW Arun garu, I usually read each of your posts three times to make sure I didn't miss anything the first two times.
I am onlee a blind man of Hindoostan, pls don't bank on me too much;)
IMHO PAD is a development platform (because other platform was not ready back in 2002 when the program took off. But adequate to prove out the system. ABM system is a big system of which the interceptor missile is only a small component, one that can be easily enhanced or changed out. Now that AAD and Shourya have taken to the sky, the real motors that will take interceptor to sky will soon be brought in. For lower altitude interception AAD is already solid fueled and is in the final missile configuration.
For High altitude interception of all classes of missile (including ICBM) one will need solid fulled first stage, and as press reports are already out, the REAL ONE is called PDV. PDV will sport a solid fulled booster and the upper stage will remain the same as what it is today on PAD.
DRDO readies shield against Chinese ICBMs : India today
For Phase 2, Dr Saraswat said that the organisation had already begun development of a two-stage hypersonic missile interceptor called the PDV and it would be ready in two years. It had also put in place the building blocks for developing extended range radars of over 1500 km.
Unlike the exo-atmospheric interceptor, which was test-fired on Friday, the PDV has two stages, a liquid and a solid. The PDV is a longer missile with two solid stages. It is in the class of the THAAD or Terminal High Altitude Area Defence missiles deployed by the United States as part of its missile shield beginning this year. THAAD boasts of missiles which can intercept ballistic missiles over 200 km away and tracking radars with ranges of over 1000 km.
Don't expect a new solid booster for this PDV, it will be .... . . . you can guess it ... same as the Shourya's second stage (main motor) 0.74m diameter, 6 meter long, weighs about 3.6 tonne.
From my Shourya/Sagarika missile article in IDR:
Second Stage: This 6 meter long stage weighs about 3.6 tonne and generates 16 tonne thrust. Case-bonded HTPB-based composite propellant with low burn rate is ignited by a small pyrogen ignition motor. The case is made of 250 grade maraging steel to maximize fuel mass fraction that is critical for scalable payload versus range flexibility. Its nozzle is made of composite material with metallic backup and carbon phenolic liners. The interstage coupling uses a soft-stage separation mechanism and retro rockets for reliable and safe stage separation.
Your article on Shourya was, as usual, oustanding. I only hope a laser inertial confinement facility can be built to confirm functioning of our TN weapons as outright testing, I fear, will be politically/economically impossible for quite some time.
Dhanyavaad.
As for laser inertial confinement facility for TN bum, .... Jai Maataa Di.
Onlee Maa Bhagwati can save India from the raak-shucks that (mis)rule the apex.