Upgrading the Ubiquitous 105mm IFG

Arming the Mountain Strike Corps

Article by Shwetabh Singh (Twitter @singhshwetabh71)



‘Ultima Ratio Regum’ used to be inscribed on French cannons on the order of King Louis XIV, which literally translates as “The final Arguments of Kings”. Rightly said, for artillery was, remains and will continue to remain, one of the most vital decider on the battlefield.

Since the Bofors imbroglio of the 1980s, no artillery guns were ordered for the Indian Army for over three decades, during which time the artillery arm faced major reductions with our SPG capabilities virtually demolished while towed artillery suffered. But for indigenous production of some pieces, our field artillery capabilities were degraded.

Light amongst the darkness however, and a backbone of our field artillery, has been the 105 mm IFG/LFG or Indian Light Field Gun. Used in quantity by the army during recent conflicts like Kargil, this gun maintains its dominance even today, having been introduced in the 1980s and can well contend being one of the most effective extant in terms of range vs weight of its class. The LFG Mk.2 has a reported range of 17.2 km which surpasses even its Russian equivalent D-30 122-mm field gun (15.4 km unassisted). Kargil was the debut for our Bofors but behind the shadows was the IFG, providing suppressive fire support to the advancing infantry and remained the most proliferant in this mountain war.

The IFG/LFG brings some major advantages to the Army in the northern and northeastern borders, albeit with lesser firepower than that of a 155 mm against well protected structures like steel reinforced bunkers. Mountainous terrain allows for only light artillery to be transported and the only other gun which can be airlifted by helicopters is the M777 ULH and possibly that designed by the Kalyani Group. The IFG/LFG can be positioned more quickly than the ULH, and because of the latter’s limited numbers, the IFG/LFG must be deployed to cover most of the Indo-Chinese borders and those with Pakistan. The IFG/LFG is of rugged design and coupled with its light weight (lighter than M777) is much more versatile in deployment through various means. The gun can be disassembled and transported on mules or underslung by helicopters (including the Cheetah) or air dropped along with para-gunners.

The most important factor is that the IFG/LFG is already in service with the Indian Army’s Regiment of Artillery in quantity, is very affordable with virtually almost no logistical issues remaining. Three decades have passed since this gun was first inducted and its replacement, if found, would take around another decade. Over the past 3 decades, the IFG has obviously aged and could use some upgrades. In this article, we’ll look at some of these prospects, which would make a future gun complement the IFG rather than replace it.

Mi-17 of IAF transporting an IFG/LFG at Tuting ALG. Pix: MoD

One of the most vital factors in a modern artillery gun is its FCS or Fire Control System. To take the IFG into the next decades of the 21st century, a digital FCS is imperative, making it effective even in bad weather conditions as this can compensate for variables such as air density and wind speed and even forewarn wearing off the barrel and distortions owing to heat. BEL has designed an indigenous FCS for the FH-77B (Bofors) guns, which proved their worth during Kargil in 1999, accurately impacting on targets over great ranges but none such system exists for the IFG/LFG. Incorporating this system on the IFG should be priority, and since there are programmes to modernise other guns such as the L40/70, why not also the IFG/LFG?

An important advantage of the 105 mm IFG/LFG is its relatively long range, 17.4 km (E1) 17.2 km (E2), compared to contemporary guns like the British L118 105 mm (which gun shares a development history with ours) also having a max range of 17.2 km, the American derivative M119 having 11.5 km range for a standard M760 HE round and upto 19.5 km with a charge 8 ( with RAP), the Russian D30 2A18 122 mm 15.4 km with a HE round and 21 km with a RAP. A common practice used by artillery units to increase range of the guns without any major changes to the gun itself, is to use ammunition like Extended Range 105mm Base Bleed Projectile or a 105 mm Rocket Assisted Projectile (RAP).

The classic: 105/37 mm Light Field Gun Mk.II (LFG)

Base Bleed rounds can have significant impact on increasing of range (upto 30%), increasing the IFG/LFG’s maximum range of 17km to 22–27 km. One cannot emphasise this enough! A RAP round is also very effective for increasing range: the D30 2A18 can shoot upto a 21.9 km using a RAP, compared with the original 15.4km while the M119 uses a M913 HERA (High Explosive Rocket Assisted) to significantly increase its range from 14.5 to 19.5 km. HERA rounds are not only common in the 105mm field gun category, almost all NATO armies field HERA rounds to increase their 155mm howitzer range to 30 km. An indigenous production line of HERA rounds would not only help in increasing the 105 mm’s range but also of any other 155mm we may procure (India bought 145 M777 ULH from US and it is reported that we would be using indigenous rounds for the gun). Since these are meant for the planned Mountain Strike Corps, such rounds would increase the area of lethality. The RAP could indeed increase the IFG/LFG’s range to some 22 kms and the OFB is producing 155 mm HEER Base Bleed rounds but not for the 105mm IFG.

With increased range, accuracy or CEP (Circular Error Probability) becomes an important aspect in determining the capability of a gun. Unguided shells are good for ‘smothering’ enemy defences or static positions but in times of limited intel and/or close proximity of ‘friendlies’ and ‘enemies’, precision-guided shells become the vital factor. As of now, India does not manufacture any guided munitions of 105mm calibre so procuring Precision Guided Kits is an option. These kits transform unguided shells into guided ones, similar tactics were used during Kargil with Laser Guided Bombs kits. These kits are cheaper than the guided rounds themselves, can reduce CEP drastically. An unguided shell, like the M549A1 at 30km, has a CEP of 260m while with a PGK it becomes a mere 10m. A bunker at the end of a street will no longer be problem to hit for such an artillery gun. One such possible system has been developed by IMI with a CEP of 10m at 23 km which would be very interesting for an upgraded IFG/LFG.

There is also a completely revamped version of the IFG/LFG being offered by the Kalyani Group in cooperation with the Mandus Group, which is the Garuda 105mm Ultra-Light Field Gun. This has many commendable features, its weight is being less than 1000 kgs compared to the 3 tonne IFG/LFG, it can be fitted on any light tactical vehicle, has less parts than the original gun and best of all, features a digital FCS. Most recently the Garuda 105mm was seen at the 5th Bhartiya Vigyan Sammelan, Pune in 2017. The Kalyani Group has also tested new piston mechanism to absorb shock with a 40% reduction in recoil as in the Garuda 105. The complete gun mount weighs only 1500 kgs and can be mounted on armoured vehicles, but the Army has not yet formalised is requirement.

The last order of the IFG/LFG was for about 150 guns for the Mountain Strike Corps, even as an order for M777s was being worked out. With about 2400 units of the IFG presently in service, it would be unthinkable to ignore its upgrade potential, as it is an obvious force multiplier.