Flexible response: Special ammunition and artillery fire power

In recent years the distinction between the gun and the missile has become blurred in the employment of artillery on the battlefield.

India too is following this trend with the recent test of the short-range Prahaar missile that is intended to cover the distances beyond what the 105 mm and 130 mm field guns, the Bofors howitzer, the Pinaka multi-barrel rocket launch system, and the Russian Smerch rockets can hit enemy targets from the forward edge of battle to depths of up to 80 km behind enemy lines.

These help to disrupt enemy lines of communication and supply routes, troop reserves and artillery emplacements making it difficult to maintain either his offensive or his defensive posture.

The Prahaar with a range of up to 150 km will deal with the gap between these artillery systems and that of the operational Prithvi missiles that cater to distance between 150-250 km.

This kind of ‘layering’ helps in what is known as flexible response to enemy threats which could escalate very quickly from the battlefields to the vital points and vital areas that sustain its war effort.

The Prahaar on a six-pack road-mobile launcher is a ballistic missile that executes a 35 km high trajectory before arriving within less than ten meters of the target within 250 seconds.

The producer Defence Research and Development Organization has described the Prahaar as a cost-effective, quick-reaction, all-weather, all terrain, highly accurate battlefield support tactical system.

Clearly, it covers everything any fighting man would wish for. Perhaps, it is little faster arrival on target than the three minutes ten seconds that it takes to complete its design trajectory.

What has been tested is clearly Mark I of a new weapon system. Improvement in future generations would become part of the continuous process of product improvement and modernization.

Modernization of the Indian artillery has been neglected since the Bofors howitzer scandal broke about a quarter century ago. If the same Bofors weapons had not become the mainstay of the Indian artillery phalanx deployed against the Pakistan Army in the Kargil war it would have been treasonous in the extreme to have neglected this crucially important segment of any battlefield.

Warhead modifications

In recent years modernization of artillery has taken new routes in that modifications are being made in the warhead rather than in the weapons platform with the intention of increasing range and lethality in a cost-effective manner, not that modern-day artillery shells come cheap.

Precision-guided munitions are worth their weight in gold because of the first-round-hit possibilities they open up.

In artillery, rocket assisted takeoff and base-bleed systems have long been part of the standardization process to achieve longer ranges.

The trend then changed to improving the yield per warhead (lethality) and precision-guidance (accuracy) and this has been achieved largely with the introduction of nuclear warheads for indiscriminate destruction in the tactical battlefield to the more humane fuel-air explosives that are just a few feet removed from the nuclear threshold in their lethality.

Generically known as thermobaric warheads they are being designed for use from hand delivered grenades and shoulder-fired rocket-propelled grenades to artillery shells and missile warheads and their effect is described variously as pressure weapons and vacuum bombs and, as stated earlier, their lethality is very nearly equal in its destructive capability (except that there is no radiation fallout) to that of a nuclear weapon size for size.

Except, as the name implies, in regions that are so high that the ambient air on which the system depends for its blast effect is too rarified to combine into a lethal mixture with the fuel-ranging from powdered metals like aluminum and magnesium to petroleum jelly or any other volatile material that enables ignition in combination with ambient air.

Nonetheless it does not follow that just combining the ingredients will ensure an adequate explosion. A great deal depends on the mix, that is, how fast the fuel mixes with the air and how well-timed is the ignition when the mixture reaches its optimum level which in turn depends on the distance between the fuel container and the ignition box.

It is all governed by the upper and lower limits at which the volatile fuel explodes in its interaction with the ambient air. Early experiments tended to be fizzlers because either the mixture dispersed too fast for an ignition to take place or the mixture was too “rich” in its fuel content to explode rather than burn.

But when you get it right the bang is really big. The US has been using this technology to induce shock and awe and, before the Russians outdid them in the yield per bomb, theirs was the mother of all bombs (MOAB).

Smart weapon

The Russians called their own creation as the father of all bombs. However, these are freefall air-delivered bombs (not artillery shells delivered by guns, howitzers or multi-barrel rocket launchers) but the technology is increasingly being applied to the artillery weapons as well in appropriately smaller packaging.

The US has used fuel-air explosive technology extensively in Iraq and Afghanistan. The last phase of chasing Al Qaeda supreme Osama bin Laden out of the caves of Tora Bora saw extensive use of fuel-air explosives, also called “Daisy Cutters”.

That Osama survived the massive assault may well have been because he was whisked away by the extra-tall fugitive from the Tora Bora region so fast that he was already in a Pakistani safe house before the bombardment began.

If he had stayed around he would have choked to death because the vacuum created by the explosion would have sucked out all the air from the caves.  

Most nations with large artillery regiments have introduced FAE technology in their warheads. China has a large arsenal and it should be expected that it has supplied the 155 mm shells to its “all-weather friend” Pakistan.

It is as if Pakistan is an extension of China and it would be natural for China to supply the latest technology and weaponry to such a friend so as to maintain a credible extra-regional outreach verging on annexation or “frontline State” status for Pakistan.

India too has worked on the technology at its Armament Development Establishment in Pune and has apparently mastered it. The 155 mm howitzer shell is amenable to conversion to a fuel-air explosive warhead as are those of the 214 mm Pinaka and the even larger diameter Smerch MBRLS.

The use of the Pinaka and Bofors howitzer in a direct-fire role highlights the potential of introducing fuel-air explosive warheads.

In both the anti-personnel as well as the anti-fortification role in mountainous terrain these weapons have played a stellar role in Kargil so it would be logical to expect that their capabilities are enhanced given that much of the warfare of the future will be fought in the high Himalayas be it with Pakistan or China or both.

On the other hand the characteristics of the Prahaar surface-to-surface missile and its reported accuracy of less than 10 meters (33 ft) if capped with a FAE warhead with its near-nuclear yield means that a “first round hit” is assured if surveillance and target acquisition (SATA) equipment has the range and accuracy to match.

Among the other innovations that are being attributed to artillery is that of the electro-magnetic pulse (EMP) released by a large explosion in the atmosphere. The characteristic of the EMP is that it disrupts communications.

Any such device could affect the network centricity of the command structure and slow down operations against an enemy in the defensive/offensive role.

However, the range of the EMP created by a conventional warhead is confined to tens of kilometers as compared to the hundreds of kilometers of a nuclear blast. Hence the utility of the conventional warhead as an EMP weapon is very limited and hence questionable.