K-4 (missile)

K-4 is a nuclear capable intermediate-range submarine-launched ballistic missile developed by the Defence Research and Development Organisation of India to arm the Arihant-class submarines. The missile has a maximum range of about 4000 km.

Development
The development of the K-4 was undertaken after facing significant difficulties in compacting similarly capable Agni-III to equip INS Arihant which has a limited 17 m diameter hull. K-4 has range comparable to Agni-III with major length reduction from 17 m to 12 m. The gas-booster designed for K-4 was successfully tested from a submerged pontoon in 2010.

Agencies responsible
The High Energy Material Research Laboratory (HEMRL) and the Advanced Centre for Energetic Materials (ACEM) of the DRDO have been involved in developing the three motors responsible for propelling the K-4, the systems responsible for separating the stages of K-4, the low-thrust boosters, the gas generator and other components. The launch system of K-4 has been developed by the Naval Systems Group of the Research and Development Establishment (Engineers).

Description
The K-4 is a submarine-launched ballistic missile which is composed of two stages. The missile is reported to be 12 m long with a diameter of 1.3 m and weighs nearly 17 tonne. It can carry a warhead weighing up to 2 tonne and is powered solid rocket propellant. The DRDO stated that the aim of the missile was to achieve a high accuracy. As a countermeasure against ballistic missile defence systems, the K4 can perform three-dimensional maneuvers.

Deployment
The missile will be deployed on the Arihant-class submarines.