Artillery amunition includes the projectile or shell; propellant; primer to ignite the propellant; cartridge case to hold the propellant, bursting charge and fuse. The size of the projectile is expressed in terms in terms of calibre, which is the diameter of the projectile as measured in mm or inches.

Precision Guidance Munition (PGM)

A PGM (also called smart weapon, smart munition, smart bomb) is a guided munition designed to precisely hit a specific target. The terminal guidance unit is designed to sense emitted or reflected electro -magnetic -radiation. PGMs is the area where artillery can improve radically to provide devastating, accurate and almost instant fire. PGMs could also punish infrastructure targets with less collateral damage; engage radars, integrated air defence systems, and command and control centres effectively. PGMs would be self guided and thus could be launched from a longer range when operating from an airborne platform thus reducing the risk to the pilot and the aircraft. PGMs used by US Forces have been successful in the Middle East, forcing the adversaries to change their tactics by widely dispersing their forces. PGM Components include a Guidance Unit which discriminates differences in energy received by its sensor; and a Tracker Unit which controls the flight of the PGM to the target.

Some examples of current PGMs

M982 Excalibur. This is a 155mm extended range guided artillery shell developed by Raytheon Missile Systems and BAE Systems AB. It is a GPS-guided munition, capable of being used for close support of within 75-150 m of friendly troops. It has a range of 40-57 km and CEP (cumulative error of probability) of around 5-20 m.

M712 Copperhead. This can be fired from a 155mm calibre gun, is fin-stabilised, terminally guidance by laser, explosive shell is designed to engage hard point targets such as tanks, self-propelled howitzers or other high-value targets. It can be fired from many types of 155mm calibre artillery guns like M777, M198, etc. The projectile has a minimum range of 3 km and a maximum range of 16 km. For Copperhead to function, the target must be illuminated with a laser designator. Once the laser signal is detected, the on-board guidance system will operate the steering vanes to manoeuvre the projectile to the target. Copperhead operates in two modes. Ballistic mode is used with good visibility and high cloud ceiling. Glide mode is used with low visibility and low cloud ceiling.

M898 155mm Sense and Destroy Armour (SADARM) shell. SADARM can be fired from a normal 155mm artillery gun. SADARM shell has a nose-mounted M762/M767 fuse set to burst at 1,000 m above the target for releasing two SADARM submunitions. The submunition is ejected from the projectile with the help of two parachutes. Each sensor with the submunitions has a milli- meter radiometre radar which scans an area of 150 m in diameter, tracks and guides the submunition onto the target.

Non-Line-of-Sight Launch System (NLOS-LS)

The NLOS-LS was a technology demonstration programme focused on beyond line-ofsight fires for the Army’s Future Combat System. The programme was earlier managed by DARPA (NetFires). The aim was to develop and test a containerised, platform-independent multi-mission weapon concept as an enabling technology element for the FCS. The NLOS-LS is claimed to defeat all known threats, is air deployable and enhances the situation awareness and survivability due to standoff target acquisition and extendedrange, non-line-of-sight engagements. Both missile types have a self-locating launcher and a command and control system compatible with the FCS. The NLOS-LS is one of the alternative system to provide artillery support in place of the Crusader artillery system. The system is platform independent with the concept of vertical-launch set of missiles with a command and control system in a box. Normal artillery is dependent upon the platform. The system has 16 compartments out of which 15 hold missiles and one compartment holds the command and control system. The missile has a soft launch which means that the recoil is very little unlike a gun which has a heavy recoil.

Type of Missiles. It has two type of missiles. The first is a Precision Attack Missile (PAM), which was formerly developed by Raytheon Corporation alone. The PAM can be utilised for both hard and soft targets at a range of 0.5-50 km. The second is a Loitering Attack Missile (LAM), which has continued to be developed by both Lockheed Martin and Raytheon. It carries a laser detection and ranging (“ladar”) seeker, a turbojet motor, and wings that extend on launch. The missile has a 70 km range with a 30-minute loiter time. It is able to loiter over targets of interest, do automatic target recognition and attack targets on its own. When fully developed, LAM will enable the Army with a single shot, to search large areas for specific targets with a single missile. LAM is envisioned as an autonomous, loitering hunter-killer with a 200+ km range and a 45-minute flight time.

DARPA’s Magneto Hydrodynamic Explosive Munition (MAHEM) Programme

Explosively formed jets (EFJ) and fragments and self-forging penetrators (SFP) are used for precision strike against targets such as armoured vehicles and reinforced structures. The Magneto Hydrodynamic Explosive Munition (MAHEM) programme offers the potential for higher efficiency, greater control, and the ability to generate and accurately time multiple jets and fragments from a single charge. The programme will demonstrate compressed magnetic flux generator (CMFG)-driven magneto hydrodynamically formed metal jets and SFP with significantly improved performance over EFJ. MAHEM offers the potential for multiple targeted warheads with a much higher EFJ velocity, than conventional EFJ/SFP which will increase precision and lethality. MAHEM could also be packaged into a missile, projectile or other platform, and delivered close to target for final engagement.

Nuclear shells

US developed one of the first artillery guns called ‘Atomic Annie’, in 1953. The gun fired a 15-kiloton atomic projectile to a range of 17 miles (about 27 km) and weighed 85 tonnes which became completely unwieldy in the field. It was replaced by a 203mm how which could fire nuclear projectiles with a yield ranging from 0.1 to 12 kilotons.

High Explosive Guided Mortar (HEGM)

The role of the HEGM is to provide an integral indirect mortar fire capability that can support the infantry at close quarters in all weather and terrain conditions. It will be the most suitable weapon for manoeuvring battalions and special operations. Its accuracy will provide ‘first shot- bulls eye’ thereby removing the ‘Ranging Process’ which will reduce the quantity of mortar bombs required for an operation, reduce the time of mortar fire and minimise the collateral damage in an urban environment. The XM395 will engage targets as close as 500 m threshold (T) and 1,000 m objective (O). This implies that own infantry can get safely to the target as close as 500 m when the target range is 1,000 m. In another scenario the range can be 6,500 m (T) and 15,000 m (O). The 120mm cartridge is being developed in an incremental manner to increase range, system manoeuvrability, improve lethality etc. Full Operational Capability is likely to be achieved by the middle of 2022.

Rocket Launcher

A modern US multiple launch rocket system (MLRS) is a high-mobility automatic system based on a M270 weapons platform. The basic MLRS tactical rocket warhead contains 644 M77 munitions, which are dispensed above the target in mid-air. The dual-purpose bomblets are armed during freefall and a simple drag ribbon orients the bomblets for impact. Each MLRS launcher can deliver almost 8,000 munitions in fewer than 60 seconds at ranges exceeding 32 km. Other mission-oriented rockets include the extended-range (ER) rocket, the reducedrange practice rocket (RRPR) with a range of 8 km to 15 km and the AT2, which dispenses 28 anti-tank mines a round. The extendedrange rocket, first fielded in 1998, carries 518 improved munitions in excess of 45 km.

Indian Perspective

Guns. There is no development in gun ammunition although a statement was made in 2016 that India make its own ammunition for all gun systems in India. Defence PSUs and the private sector will really have to gear up to the challenge of modern artillery ammunition, rockets and missiles.

Rocket Launcher. India has great success with the DRDO developed Pinaka MLRS. The system has a maximum range of 40 km for Mark-I and 75 km for Mark-II, and can fire a salvo of 12 HE rockets in 44 seconds. The warhead is 100 kg HE with option of Fragmentation HE; Incendiary; Anti-tank/anti-personnel and anti-tank bomblets.

Sudarshan. Sudarshan is an Indian laser-guided bomb kit, developed by DRDO’s Aeronautical Development Establishment with technological support from Instruments Research and Development Establishment for the Indian Air Force.

Missile Systems. India has a surface to surface Prithvi missile and BrahMos cruise missile, both of them are being further improved in precision, range and lethality.