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.[8] The missile has a maximum range of about 4000 km.[9][10]
| K-4 | |
|---|---|
 K-4 SLBM launch | |
| Type | Intermediate-range SLBM |
| Place of origin | India |
| Service history | |
| In service | 2020s[1] |
| Used by |  Indian Navy |
| Production history | |
| Designer | Defence Research and Development Organisation |
| Manufacturer | Bharat Dynamics Limited |
| Specifications | |
| Mass | 17 t (19 short tons)[2] |
| Length | 12 m (39 ft)[2] |
| Diameter | 1.3 m (4.3 ft)[2] |
| Warhead | Strategic nuclear weapon |
| Warhead weight | 2,500 kg (5,500 lb)[3] |
| Engine | Two stage solid rocket motor[4] |
| Propellant | Solid rocket propellant[4] |
Operational range | 4,000 km (2,500 mi)[5][6] |
Guidance system | Mid-course: Inertial navigation system with GPS/NavIC satellite guidance, Terminal: Terrain contour matching[7] |
Launch platform | Arihant class submarines |
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-metre (56 ft) diameter hull. K-4 has range comparable to Agni-III with major length reduction from 17 metres (56 ft) to 12 metres (39 ft). The gas-booster designed for K-4 was successfully tested from a submerged pontoon in 2010.[11]
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).[12]
Description
The K-4 is a submarine-launched ballistic missile which is composed of two stages.[4] The missile is reported to be 12 metres (39 ft) long with a diameter of 1.3 metres (4 ft 3 in) and weighs nearly 17 tonnes (19 tons). It can carry a warhead weighing up to 2 tonnes (2.2 tons) and is powered solid rocket propellant. The DRDO stated that the aim of the missile was to achieve a high accuracy.[2] As a countermeasure against ballistic missile defence systems, the K4 can perform three-dimensional maneuvers.[1]
Deployment
The missile will be deployed on the Arihant-class submarines.
| Class | Vessel | Tonnage | Silo Capacity | Status |
|---|---|---|---|---|
Arihant class | INS Arihant | 6000 t | 4 × K-4 SLBM | Operational |
| INS Arighat | Operational | |||
| INS Aridhaman | 7000 t | 8 × K-4 SLBM | Construction | |
| S4* (codename) | Construction |
Testing
| Date/Time (IST) | Configuration | Launch Site | Duration | Outcome |
|---|---|---|---|---|
| Operator | ||||
| Payload | Range | Function | ||
| Remarks | ||||
| 15 JAN 2010 | Submerged Underwater Pontoon | Visakhapatnam Coast | — | Success |
| DRDO | Single mass simulator | — | Developmental launch | |
| Tested secretly off Visakhapatnam on January 2010, the 10-m long and 1.3-m wide missile emerged from a pontoon submerged 50 m underwater and breached the surface. Painted black and white so that it can be distinguished in water. The test validated the ability of a 20-tonne projectile to withstand 50 kg of water pressure and eject from a submerged launcher before engaging its rocket booster.[15][16] | ||||
| 24 MAR 2014 | Submerged Underwater Pontoon | Vishakhapatnam Coast | — | Success |
| DRDO | Single mass simulator | 3000 km | First test launch | |
| The launch took place from a pontoon submerged more than 30 metres deep in the sea off the Visakhapatnam coast. After a powerful gas generator ejected it from the pontoon submerged in the Bay of Bengal, the K-4 missile rose into the air, took a turn towards the designated target, sped across 3,000 km in the sky and dropped into the Indian Ocean.[17] | ||||
| 07 MAR 2016 | Submerged Underwater Pontoon | Vishakhapatnam Coast | — | Success |
| DRDO | Single mass simulator | — | Second test launch | |
| The K-4 missile was fired at a depressed trajectory. Starting from successfully clearing the launch tube and breaking the water surface to stage separation and maintaining the ballistic trajectory, the missile achieved all parameters before zeroing in on the pre-designated target with high accuracy. The trial was stupendous and a copy book success.[18] | ||||
| 31 MAR 2016 | INS Arihant - Onboard SLBM Silo | Vishakhapatnam Coast | — | Success |
 Strategic Forces Command | Single mass simulator | 700+ km | Third test launch | |
| The missile was successfully tested from INS Arihant, 45 nautical miles away from Vishakhapatnam coast in Andhra Pradesh. The missile with a dummy payload was launched from the submarine in full operational configuration. The trial was carried out with the support of the personnel of Strategic Forces Command (SFC) and the DRDO provided all the logistics. The missile was fired from 20-metre deep and it covered more than 700 km before zeroing on the target with high accuracy reaching close to zero error.[19][20][21][22] | ||||
| 17 DEC 2017 | Submerged Underwater Pontoon | Vishakhapatnam Coast | — | Failure |
| DRDO | Single mass simulator | — | Fourth test launch | |
| K-4 missile did not activate during the test, with its battery getting drained after the launch command was given. It is believed that DRDO scientists were even unable to retrieve the missile from the test pontoon following the failure.[23][24] | ||||
| 19 JAN 2020 1:21 PM | Submerged Underwater Pontoon | Vishakhapatnam Coast | 21 min | Success |
| Strategic Forces Command | Single mass simulator | 3500 km | Fifth test launch | |
| The test was conducted from a pontoon nearly 30 nautical miles from Vishakhapatnam coast. The trial was carried in association with Strategic Forces Command (SFC) while the DRDO provided all logistic supports. The missile zeroed on the target with high accuracy reaching close to zero circular error probability. The missile travelled nearly 21 minutes and covered its full range of over 3,500 km.[25][26] The test comes after several postponement for the last three months with that of November attributing to a cyclone.[27][28][29] | ||||
| 24 JAN 2020 | Submerged Underwater Pontoon | Vishakhapatnam Coast | — | Success |
| Indian Navy | Single mass simulator | — | Sixth test launch | |
| Last developmental trial of K-4 making the weapon ready for its series of production and induction in the Armed Forces. Fired from a pontoon nearly 45 nautical miles off Visakhapatnam coast from a depth of around 50 metre, the missile was tested for a reduced range to validate new technologies incorporated in the system. The missile achieved all mission parameters before zeroing on the pre-designated target with high accuracy. The weapon was tested in its deliverable configuration with the active participation of Navy personnel.[30][31] | ||||
