India’s missile programme

An Indo-Israeli joint venture Kalyani Rafael Advanced Systems is going to manufacture Spike, an anti-tank guided missile near Hyderabad. While a rocket is an unguided, rocket-powered weapon, with no steering ability, a missile is a self-propelled weapon, often rocket-powered, that has some kind of guidance system towards its target, according to stackexchange.com.

A cruise missile is a guided missile used against terrestrial targets that remains in the atmosphere and moves at nearly constant speed. Cruise missiles are designed to deliver a large warhead over long distances with high precision; that is, small circular error probability. A ballistic missile is launched directly into the high layers of the earth's atmosphere.

It travels well outside the atmosphere and then the warhead detaches and falls back to earth. It follows the path of a ball thrown upwards which falls down. Since it depends on gravity to reach its target, it's called a ballistic missile. Missiles that travel at a speed less than the speed of sound (Mach 1) are called subsonic cruise missiles.

Mach is the ratio of the speed of a body to the speed of sound in the surrounding medium. It is often used with a numeral (as Mach 1, Mach 2, etc.) to indicate the speed of sound, twice the speed of sound (340.29 metres a second), etc. A supersonic missile flies several times the speed of Mach.

The Integrated Guided Missile Development Programme (IGMDP) is an is managed by Defence Research and Development Organisation (DRDO). The project commenced in early 80s under the leadership of Dr APJ Abdul Kalam. Four projects, to be pursued concurrently, were born under the IGMDP: Short range surface-to-surface missile (code-named Prithvi); Short range low-level surface-to-air missile (code-named Trishul); Medium range surface-to-air missile (code-named Akash) and Third-generation anti-tank missile (code-named Nag).

Brahmos is the first supersonic cruise missile known to be in service. It has flight range of 290-km with supersonic speed all through the flight, according to www.brahmos.com. It represents the fury of Brahmaputra and the grace of Moskva rivers. It is a joint venture with Russia.

Dhanush is a variant of the surface-to-surface or ship-to-ship Prithvi III missile, which has been developed for the Indian Navy. Advanced BRAHMOS Block III land attack cruise missile system was successfully tested in May. A Quick Reaction Surface to Air Missile (QRSAM) was successfully flight tested in July.