The last line of defence

Ours is an era of super advanced technologies. The modern battlefield, as one must have come to know, is technologically hyper advanced. Victories in battles these days are no longer won with numerical superiority, but with technological might. Battles have become short, intense and focused. This is the age of air-superiority and air-dominance fighter planes, of precision guided munitions and of long range cruise missiles, of theatre ballistic missiles and SLBMs. When such awesome firepower brought to bear, is there a chance to survive the onslaught? Yes. The latest generation of SAMs (Surface to Air Missiles) helps us do just that. With mind-boggling accuracy and an incredible reach, these technological marvels are the ultimate weapons for strategic self-defense.

We explore some of the best and the latest medium to long range air-defense platforms that the world has to offer.

To understand and appreciate the importance and the effectiveness of these machines, let us understand some of the key terms that would be used while exploring them.

The Interceptor – A missile fired by a SAM battery at the incoming hostile target(s).

The Battery – The term used to address a bunch of launchers (each having multiple interceptor missiles), radars and the communication equipment.

The Radar – The eyes and ears of the SAM system. The radar (ground based) provides information about the hostile target and guides the interceptor missile to the target.

The Seeker – A guidance module present in the interceptor. Provides and uses real time target information. The information is sent to the ground radar which uses this info to provide mid course guidance updates.

Range – Usually denotes the range of the interceptor missile, the actual distance the interceptor missile can fly, chase and attempt to kill the hostile target.

Interception mode – Denotes the way the interceptor will kill the incoming hostile target. The interceptor can be designed to carry either a proximity kill warhead or a hit-to-kill warhead.

IFF – Identification Friend or Foe module. A module that helps the air-defense systems know if the aircraft they are tracking is friendly or hostile.

The Game Plan

The usual battlefield scenario is something like this: The SAMs are deployed usually to protect high value assets such as Nuclear power plants, vital bridges, communications facilities, military bases etc. When the adversary tries to attack and destroy the assets he would invariably run into the air-defense systems deployed there. The adversary may try to neutralize the threat using bombs dropped from aircraft, cruise-missiles or ballistic missiles. Almost all the air-defense systems roughly follow the framework of steps mentioned below to engage the hostile incoming target. For ease of understanding, let’s assume a single hostile aircraft tries to intrude into our territory.

è The radar picks up the incoming target, tracks it based of its flight path the system assigns the target priority.

è Once the target is within a certain range the IFF swings into action to determine if the target is friendly or hostile.

è If deemed hostile, the systems go into the engage mode and continuously track the target.

è The firing officer is intimated about the incoming hostiles and he/she takes a call on whether the target is to be engaged or not.

è Once the firing officer gives the system orders to fire, the system launches one or more missiles at the target.

è After the launch of the interceptors the radars keeps tracking both the target and the interceptor. The radar provides mid-course updates to the missile about the current location of the target and the possible flight path. This helps the interceptor to determine a feasible collision course.

è Once the interceptor comes within a certain distance of the target it de-links itself from the ground radar and proceeds with its own on-board radar.

è Based on the kind of maneuvers performed by the target the interceptor usually decides the best mode of kill (Hit-to-kill or proximity kill) on the spot.

è If the interceptor’s on-board computers predict a direct hit, they activate the hit-to-kill mode and the explosive warhead is detonated only when the interceptor strikes the target.

è If the interceptor’s on-board computers predict a near miss (due to excessive evasive maneuvering by the target) then the proximity kill mode is activated, allowing the missile to get the target within the ‘lethal radii’ of the proximity warhead. Once within the lethal radius, the warhead explodes disbursing thousands of fragments that tear up the target’s surfaces making it unfit for a proper aerodynamic flight.

Some systems follow slightly more complex steps and they get even more so when there are multiple adversaries mounting an attack.

Let us now explore some of the well known air-defense systems of the world.

MIM-104 (The Patriot) (USA):

Probably the most recognizable of all air-defense systems, the Patriot gained fame during the first gulf war. The Patriots were deployed to defend friendly countries in the gulf region from the infamous Iraqi ‘scuds’. The initial versions of the Patriot boasted of an impressive range of 160 KMS. The missile had a bit of success but was overhauled and updated extensively. The up rated and the upgraded PAC-3 is the latest and the most capable of all the versions of the Patriot. The PAC-3 (Patriot Advanced Capability) has upgrades to almost all the features of the system. The radar, the software, the seeker and the missile itself were upgraded extensively to give the system more reliability and flexibility. With the Induction of the Patriot PAC-3 the US forces obtained a genuinely versatile air-defense system. The PAC-3 is capable of engaging targets ranging from aircrafts, cruise-missiles to short-range and theatre ballistic missiles. The PAC-3 uses a new advanced seeker which turns itself into an autonomous mode of operation (delinks itself from the ground based radar) for the final chase and hits-to-kill the target.

The Patriot is manufactured by Raytheon. The Patriot PAC-3 was deployed in the second gulf war and met with considerable amount of success. The patriots successfully engaged and destroyed many Iraqi short range missiles (Scud, Al-samoud). But problems with certain sub-systems resulted in a couple of fatal friendly fire incidents. That however does not do much damage to the formidable capability of the Patriot. The US Department of defense intends to upgrade the PAC-3 further to extend its capability which in turn could offer the US war machine more strategic depth.

The Arrow (Israel):

Any discussion of air-defense systems would be incomplete without the mention of the Israeli Arrow missile defense system. Co-funded by the US and developed by Israel, the Arrow is one of the few BMD system that have been tested successfully multiple number of times. The Arrow BMD is build around the revolutionary ‘Yellow Citron’ control system and the Green pine long-range tracking radar. The Arrow is also coupled with some highly capable American military satellites to give it extra awareness of the battlefield space. The arrow interceptor accelerates to a speed of up to Mach 9 and destroys the incoming hostile target with a blast-fragmentation warhead, which enables the missile to destroy the target even when a direct hit is impossible to achieve. The Arrow’s warhead has a lethal radius of about 40 meters enabling it to destroy multiple also, if possible. The Arrow missile was to be sold to India to protect its borders from Pakistani and Chinese missile threats, but the deal fell through after staunch opposition from the US government. Now India uses the Green Pine radar technology to develop its own long range radar to be used for its Indigenous BMD (Ballistic Missile Defense) program.

The Arrow has an upgrade, the Arrow II, in the pipeline. The Arrow II is still under development and is expected to have a wide range of upgrades compared to the original system. The Arrow BMD is jointly developed by the Israeli Military Industries and the Israeli Aerospace Industries. It is worth mentioning that the Arrow has still not seen real combat yet but considering the awesome reputation enjoyed by Israel when it comes to technological ingenuity, once can say with confidence that the Arrow never cease to impress.

Aegis Missile Defense System (USA):

The Aegis BMD, a program initiated by the US DoD, is a highly versatile sea-based missile defense system providing the last line of defense for the US home land and its allies. The Aegis BMD uses the powerful AN/SPY-1 radar and the formidable RIM-161 SM-3 missile as the interceptor. The radar has a range of more than 120 nautical miles and the SM-3 can reach altitudes of more than 250 km and has an effective range of over 500 KMS. The aegis is predominantly a missile defense platform, but it is also employed against hostile aircrafts. The AN/SPY-1 tracks the incoming ballistic missile and after an initial bunch of computations and calculations about the missiles flight path, launches the SM-3. The SM-3 receives periodic updates from the launching ship about the flight path and releases the KW (kinetic warhead) for terminal chase. The ingenious KW provides the SM-3 a near unassailable edge over the incoming hostile missile. The KW uses highly sensitive thermal sensors to locate the incoming missile and hits it at it most vulnerable point. The Aegis has been successfully test fired by the Japanese forces after its induction.

The Aegis is probably the only exclusively sea based, dedicated ballistic missile defense system ever to be deployed. The Aegis is expected to work in tandem with the NMD (National Missile defense) system. With the NMD and the Aegis working in tandem, the US military expects to deploy a fool proof, world class, multi-layered missile defense system.

S-400 [Growler] (Russia):

Russians have made it a habit to regularly set high standards when it comes to air defense. Be it the downing of the famed high-flying U-2 spy plane, considered untouchable by air-defenses of that time with the giant-killing SA-2 missile or the formidable opposition mounted by the Russian air-defense systems (deemed to be obsolete, deployed by the Serbians) against the NATO jets involved in Bosnian peacekeeping missions. The S-400 (aptly named ‘Growler’ by NATO) does not seem to disappoint in this regard. The S-400 is considered the pinnacle of Russian air-defense research and development. The ‘Growler’ is an improved version of the famed S-300 family of air-defense systems. The S-300s, with an effective range of about 200 kilometers were capable of downing almost all kinds of air threats (From precision guided ammunition to cruise missiles) and ballistic missiles with a range of about 2000 kilometers. The S-400 pushes the barrier further with a range of 400 KMS and can down incoming ballistic missiles that have a range of 3500 KMS. Recent war games by leading militaries of the world has brought forth the fact that almost all the aircrafts in the world would fall prey to the ‘Growler’ leave alone the high-flying, super-maneuverable, super-stealthy and super-costly F-22 Raptor and the legendary B-2 stealth bomber. Even the much touted fifth generation fighter jet, the F-35 is thought to be vulnerable at times when it goes head to head against the S-400.

The eerie aura of S-400 received a major boost when serious concerns were raised by major western powers after news of a deal between Iran and Russia to sell S-400 to the former surfaced. The reaction from the west was one of utmost surprise and veiled fear. The S-400 is a highly capable weapons platform with remarkable battlefield survivability. Though S-400s are already deployed by Russia, it has not seen active battle till date. And when the day comes, we will know if the S-400 can really live up to the formidable reputation that it has built for itself.

The Indian Ballistic Missile Defence System:

Long has India languished under foreign sanctions, sanctions that were imposed after India’s nuclear test by the high and mighty countries of the world, sanctions that were ‘custom-made’ to bring the country to its knees. But India had other ideas, it’s strategic and space programs flourished and India surged ahead in the world arena in the field of missiles and satellite launch vehicles but the icing, was the successful interception of a ballistic missile, and by doing that India became only the fourth country (After US, Russia and Israel) to do so. India successfully gate-crashed the elite club with the successful interception of a short range ballistic missile with a two-tier missile defence system. The Indian BMD consists of two different interceptors, the PAD (Prithvi Air Defense) and the AAD (Advanced Air Defense) missiles. The PAD (to be named as Pradyumna) is a modified Prithvi missile. The missile carries a warhead that hits-to-kill. The missile has a speed of over Mach 5 and is designed to intercept the incoming missile at an altitude of around 80 KMS. The PAD forms the first line of defence. The second line is manned by the AAD missile (to be named as Ashvin). The AAD has a flight ceiling of 30 KMS and a top speed greater than Mach 4. The AAD also successfully knocked out an incoming Prithvi missile during the tests.

This system uses the locally developed ‘Swordfish’ long range tracking radar for target acquisition and missile guidance. The ‘Swordfish’ uses certain technologies from the Israeli ‘Green pine’ long range radar. The DRDO intends to develop the system as a robust two tier set-up, where two missiles (PAD and AAD) are fired simultaneously at the target to achieve ~99% hit rate.

These are some of the very few systems that stand out in terms of sheer technological brilliance. Why does air-defense, especially missile defense garner special attention? Cause it is a very critical application using extremely complex technology. An incoming ballistic missile (a missile with a range of around 2500 KMS) will enter the atmosphere to hit its target at an insane speed of 2KMS/sec. The interceptor needs to be guided to the incoming target at around Mach 5 (5 times the speed of sound) and with this you can calculate the relative speed of the two objects! An interception at such mind-boggling speeds will mean that there is literally no margin for error. A small initial miscalculation around a few millimeters will result in the interceptor missing the target by a mile. All the systems and the subsystems should work flawlessly. It should be a complete system which works in perfect synergy. That is something which is very hard to achieve. This is why only a handful of countries have managed to master it.

This is an application where there can be no excuses for failure. In a highly volatile security scenario, an attack with a nuclear ballistic missile is not unimaginable, and an attack like that could put millions of innocent civilians’ lives at risk. A successful intercept, however can save invaluable lives, protect sovereignties and help uphold justice. That is why air-defenses will always remain the most sought after machines of war in the unforgiving new-age battlefield.

Select References:

http://www.wisconsinproject.org/countries/israel/IsraelMissile2005.html

http://www.missilethreat.com/missiledefensesystems/id.52/system_detail.asp

http://en.wikipedia.org