The Road to Missile Development

India's interest in missiles dates back to the time of Tipu Sultan, the ruler of the Karnatic during the medieval period. As early as in 1958, the year the Defence Research and Development Organisation (DRDO) was formed, the then Scientific Advisor to the Defence Minister, D. S. Kothari, declared unambiguously that ballistic missiles were "undoubtedly [one of] the greatest and most portentous problems... ".

The reason for anxiety was the great reach that ballistic missiles have. Tipped with a nuclear warhead, the dangers only multiplied. Even at that time missiles and rockets formed one of the areas in which defence R&D was planned to be conducted.

The first clear indication that India was seriously considering the idea of launching the Integrated Guided Missile Development Programme came in 1979, when a committee was established, under the Ministry of Defence, with the then DRDO Director General, Raja Ramanna, as the Chair. The committee is popularly known as 'Missile Policy Committee'. Besides recommending the launching of an 'integrated missile development programme', the Committee recommended the "procurement, development and production of missiles for the three Services, in the short term, as also to build up the infrastructure in certain areas so as to take up projects for development of more sophisticated missiles in the long term".

It was almost around the time that the Missile Policy Committee was set up that the Devil Project was wound up. The Defence Research and Development Laboratory (DRDL), the lab responsible for developing missiles, was in need of an accomplished project manager. With this in view, the then DRDO Director General, Raja Ramanna, suggested in 1981 that Abdul Kalam be appointed director of DRDL, to run the missile development project.

Eighteen months later Abdul Kalam was appointed Director DRDL. Abdul Kalam led the team that successfully concluded the SLV-3 project. By this time, a considerable amount of technological and industrial and human resource were also available.

At the DRDL, a high level committee called the 'Missile Technology Committee' was formed. Deliberations in this body resulted in the formulation of the basic plan, which was later fine tuned, for the development of guided missiles.

Abdul Kalam recently wrote that the IGMDP is a product of a 'detailed study' conducted in 1982 "for evolving missile systems in order to counter the emerging threats to the security of India". A team was formed under the chairmanship of Abdul Kalam, with Z. P. Marshal, N. R. Iyer, A. K. Kapoor and K. S. Venkataraman as members, which drew up a paper, with inputs from the three services, for the Cabinet Committee on Political Affairs (CCPA) on the development of indigenous guided missiles.

Subsequently, the proposal was discussed at a presentation presided over by the then Defence Minister, Venkataraman, and finally cleared by the Cabinet. Consequently, the programme was launched on 27 July 1983 at DRDL, Hyderabad, by the then DRDO Director General, V. S. Arunachalam, amidst fanfare, in the presence of a large gathering of scientists, academicians, officers of the armed forces and production agencies.

Five projects leaders were selected, one for each of the missile projects, with Abdul Kalam as the head of the entire programme.

AGNI

Agni is an intermediate range ballistic missile (IRBM). Classically a ballistic missile is one that travels outside the earth's atmosphere, during most part of its flight, before re-entering. The missile is set into a ballistic path to prevent deflection. For most part of the missile's flight, the only external force that acts on it is the gravitational pull of the earth.

Guidance
Like the Prithvi, Agni I also relied on strap down inertial navigation. Agni II uses a more stable closed loop inertial navigation system.

Propulsion
It is a three-stage missile, with the third stage being the warhead. In the first three tests, the first stage used solid propellant rocket motor and the second stage used liquid propulsion. In the fourth and fifth tests, both the stages used solid propulsion. In solid propulsion, the propellant grain, the oxidiser and the fuel, whose physical state is solid, is stored in a chamber. When ignited, by means of an electric charge, it burns out completely at a pre-determined rate, and is expelled through a nozzle in the form of gases. The third stage is the missile's war head.

Warhead
It can carry a conventional warhead and can also carry a nuclear warhead. The warhead is enclosed in a heat shield to protect it from burning as the missile re-enters the earth's atmosphere. The four types of conventional warheads are incendiary, fragmentary, unguided munitions and guided sub-munitions. The warhead would have a maximum weight of one ton.

Range
With a warhead of one ton, the missile would be able to reach targets 1,500 k. m. away. With the weight of the warhead reduced, the missile has a maximum range of 2,500 k. m. Some reports claim that Agni has a CEP of 60 m.

PRITHVI

Prithvi is a tactical, battlefield-support missile. It is planned in three versions-for the army, air force and navy. Prithvi is 8.56 m long and has a thickness of one metre.

Guidance
The missile has the latest on-board computers operating with real time software as well as an advanced strap down inertial navigation and guidance system. The inertial guidance system "does not rely on outside reference like heat, light or electromagnetic radiation… [but] measures the distance between two points [launch and impact points] over a period of time".

Propulsion
Prithvi is a single stage missile that has a two-chamber rocket motor with storable liquid propellants. Prithvi uses fifty per cent xylidene-the fuel-and the remaining fifty per cent triethylamine and nitric acid-the oxidiser-as propellant. The missile has a shelf life of five years with the propellant loaded and twenty-five years without the propellant being loaded. Prithvi-III is a "boosted liquid propellant version, to generate more thrust-to-weight ratio…"

Range
The missile has a minimum range of 40 k. m. As stated earlier, Prithvi is planned in three versions. While the army version would have a range of 150 k. m. While the army has opted for the shorter 150 k. m. range version, the air force has gone in for the 250 k. m.-extended range-version. The naval version, now in the drawing board stage, has a reported range of 350 k. m.

Warhead
Five variants of the missile's warhead have been planned. They are: incendiary, fragmentary, unguided munitions and guided sub-munitions. While the first three variants have already been developed, the status of the fourth is uncertain. The fifth type of warhead is a nuclear warhead, whose development status, too, is uncertain.

AKASH

The Akash is a mobile area defence surface-to-air missile (SAM) system being developed for the exclusive purpose of the Indian Air Force (IAF).

Guidance
Akash uses both command guidance and active homing-the latter is used in the terminal phase. In active homing, the homing head is switched after which it starts searching for the target. Once the target is located, it is traced and active homing commences.

Tracking
The Akash missile system has multiple-target handling capability. The targets are tracked by Indra phased array radar, which can track one hundred targets at a time and is, thus, critical for the missile system.

Propulsion
The missile uses an integrated solid rocket propellant system.

Speed
The missile moves at a speed of 600 metres per second-mach 2, which means that the missile would reach the target at its full range of 30 k.m. in fifty seconds, and in a much lesser duration if the target were located within a distance of 30km.

TRISHUL

Trishul is a quick-reaction SAM "designed to counter a low level attack". The missile will be used by all the three services. The missile becomes operational at an altitude of 500 metres. It has been described as India's answer to the U. S. Patriot missiles that have been used to counter the Iraqi Scuds.

Guidance
The missile operates on command-to-line of sight guidance. In this method the guidance signal is transmitted from launch site to the missile, giving the missile its deviation from the pathline pointing from the launcher to the target, also called the line of sight(LOS). The missile has a computer on board to actuate its control mechanism to turn it towards the line of sight.

Propulsion
Trishul uses a solid dual thrust rocket motor for propulsion.

Materials
Trishul is made of aluminium alloy structures, fibre glass composites and maraging steel.

Range and Warhead
The missile has a minimum range of 500 metres and a maximum range of nine k. m. and can carry a warhead of 15kg weight.

Trishul has sea skimming capability when launched from ships. Sea skimming missiles travel at a very low height, just a few metres above the sea level, actually skimming the waves. Hence the name. The utility of such missiles lies in the fact that the low height and high speed of movement render them high single shot kill probability, besides being significantly immune to electronic counter measures (ECMs), given their small radar cross section.

While the army version of Trishul has already undergone user trials, the airforce version was flight tested, using the Pilotless Target Aircraft (PTA) as the target, and trails of the surveillance radar and fire control system of the naval version have commenced.

NAG

Nag is a third generation anti-tank guided missile (ATGM) that possesses an all-weather capability and also has top attack capability. In other words, it targets the turret of the tank, where the armour is the thinnest.

Nag's airframe is made of composite materials, which make the missile light, without compromising its strength, while its foldable wings enable it to be launched by a tube, like any other third generation ATGM.

While the first generation ATGMs are wire guided, the second generation is semiautomatic. The third generation is a fire and forget type.

Nag has been designed to be launched from 'either the Namica (BMP-2) vehicle or the Army Aviation version of the Advanced Light Helicopter (ALH). However, the exact status of the latter this version is not known. Trial launches of the missile using the Namaica have been conducted.

Propulsion
Nag uses solid propulsion. A smokeless high energy solid propellant is used in Nag. The advantage of using such propellant is that it 'would not leave tell-tale trails behind', and would, thus, enable the launcher to 'make good its escape'.

Guidance
Nag uses homing guidance. In this type of guidance, a homing head also called a seeker head locks on to the target, after receiving the target co-ordinates from the tracking radar, in its infrared or millimetric sights, before being fired. A seeker head is vital to the missile because it enables it to reach the target (home in). The seeker has already been tested.

Range and Warhead
Nag has a range of four km. The missile uses a tandem warhead. Warheads for various missiles.