Since countries are focusing on hi tech bombers to evade air defence capabilities of the opponent, now there is a greater need to build various layers of air defence systems to take on the intruding object at a multi dimensional level.
It can no longer be restricted to just “air defence” because network centricity, which is the hub of the system shielding ground forces from an enemy attack must be connected to satellites in orbit. But that is jumping the gun somewhat because there are layers and layers of defensive shields that cater to threats at varying altitudes from the exo-atmospheric (outside the atmosphere) down to the treetop level.
In the kind of nuclear dimension extant on the subcontinent none of the layers can be disconnected from each other because as each level beginning from the exo-atmospheric is penetrated the next level of defence must play its part right down to the close-in, last-minute stretch separating the warhead from the target.
If one is to begin at the ground level, post 1971 war with Pakistan the first to be replaced was the Kwadrat track mounted short range surface-to-air missile that guarded the armor and mechanized columns as a last-ditch defence along with the quadruple barreled Schilka tracked anti-aircraft gun system. It was replaced by the Tungushka gun-missile system on a unique tracked chassis that was capable of being raised or lowered to enable the commander to peer over territory beyond sand dunes and undulating terrain. When firing the missiles the carrier needs to stop but it can shoot the four barrel rapid fire artillery even on the move. It supplemented the OSA AK short-range surface-to-air missiles which did not require to be stopped for firing. The density of this air cover would depend on the appreciation by the local commander of the likely threat posed to the mechanized columns from enemy aircraft and missiles.
The arrival of the Tungushkas in India signaled that all was not well with the indigenous development of the indigenous Trishul short-range (nine km) project which was part of the Integrated Guided Missile Development Program which included the Prithvi, Agni and Akash missiles. The Trishul was subsequently abandoned and negotiations were initiated with Israel for the land version of the Barak-2 and the Spyder
The Integrated Guided Missile Development Program had envisaged the creation of weapons to bolster the air defence network beginning at the short range, through medium range of up to 18 km altitude. While the Trishul short-range missile fell by the wayside the medium range Akash surface-to-air missile has been inducted into the Army and the Indian Air Force largely replacing the ex-Soviet Pechora missile which catered for defence between the mid- and long-range capabilities.
Part of the program included the design and development of surface-to-surface missiles named Prithvi and Agni. The former covered the short to medium range while several versions of the latter have achieved ranges between 2500 km to 10,000 km. These together form the first leg of India’s nuclear deterrent by their capability to carry both conventional and nuclear warheads. The second leg of the triad is the airborne fighter-bombers. The third nuclear tipped missile to be carried on the nuclear propelled INS Arihant and its derivatives will represent India’s retaliatory strike capability.
For the long-range surface-to-air missile capability, India bought the S-300 from Russia. The missile has a range of 300 km so as to be able to reach enemy Airborne Warning and Command Systems (AWACS) aircraft that would be lurking behind enemy lines but shaping the battlefield by its onboard surveillance, track-while-scan and other avionic suites which give it a panoramic view and the ability to direct forces both airborne as well as ground-based in an integrated way.
Since 1998, after the series of nuclear warhead tests by India and Pakistan the concept of nuclear deterrence came into play with Pakistan taking an aggressive “first strike” posture and India stating a defensive “retaliatory strike” doctrine. India has been working on missilery that will intercept Pakistani strategic weapons at various stages of their ballistic path through space (exo-atmosphere) and through the atmosphere which is generally understood to be “airspace” or endo-atmosphere (or within the atmosphere) passage.
To achieve this capability India resorted to a conversion of the Prithvi surface-to-surface tactical missile into a surface-to-air strategic one (known as Prithvi Air Defence System (PADS) intended to intercept Pakistani and Chinese ballistic missiles. This system intercepts missiles fired from a range of 5000 km at a point when they are descending through space in what is known as the terminal phase. The PADS intercepts in the exo-atmosphere and a second missile also based on the Prithvi makes the interception closer to the ground but well away from the intended target which would be a major city or commercial hub. This is known as the Advanced Air Defence System (AADS). Currently cities like Delhi and Mumbai are protected by batteries of S-300, PADS and AAD missile systems against ballistic missiles and aircraft.
But this nuclearised scenario is incomplete and is, indeed, evolving as India, after ensuring that a nuclear blast does not happen over a high value targeted Indian city but well away from it. This it has to do by ensuring an interception not at the descent or terminal stage of a ballistic flight but further up in the exo-atmosphere when the missile and warhead are at the height of the trajectory and well away from the target. This has the possibility that both the missile and the warhead will fall in the enemy’s own territory. An even earlier interception, that is, at the initial flight stage when the missile and warhead are still climbing to the highest point of its trajectory, will make it a surety that the debris falls in the launcher’s own territory. Especially in the case of Pakistan which has a rather narrow “strategic depth” in terms of the width of its territorial area and its distance from the Indian border. An interception at the highest point of its trajectory could well result in the debris falling within Pakistan itself.
To counter India’s anti-ballistic missile (ABM) shield as well as its ground redeployment that will enable armor and mechanized infantry to be swiftly employed to deliver condign punishment on Pakistan for using terrorists as its proxies as was intended in Operation Parakram after the attack on Parliament, Pakistan has developed and deployed a short-range (60-km) nuclear missile called NASR. This missile has a capability of creating a total communications blackout in the electromagnetic pulse (EMP) that would result from the airburst of such a weapon. This phenomenon would tend to interfere with India’s intention of launching a retaliatory strike and making it difficult for the Strategic Forces Command to deliver its clearance for a nuclear attack to the missile silo.
India requires an airborne directed energy platform that will swat the NASR launchpads the moment activation procedures are notice. This platform will also be useful in trying to blast Pakistani nuclear missiles at the boost phase itself. “Air defence” in such an eventuality is no longer confined to the surface-to-air configuration. It acquires an “aerospace defence” ambiance.