To further strengthen its capabilities of hitting enemy targets from submarines, India is planning to test-fire the 3,500 kilometre strike-range K-4 nuclear missile from an underwater platform off the coast of Andhra Pradesh on 8 November 2019. The missile system is being developed by the DRDO for the Arihant class nuclear submarines which are being built by India. These submarines would be the mainstay of India's nuclear triad.
 
What
  1. As per plans, the DRDO will carry out test-firing of the K-4 nuclear missile from an underwater platform off the Vishakhapatnam coast. During the trial, the DRDO will test the advanced systems in the missile system.
  2. K-4 is one of the two underwater missiles that are being developed. The other one is the over 700 kilometre strike range BO-5 missile.
  3. It is not yet clear whether the DRDO will test the missile at the full strike range or shorter ranges. 
  4. However, NOTAM (Notice to Airmen) and marine warnings for long-range missile test have already been issued by India for the planned test-firing. The K-4 missile test was planned for last month but was postponed.
  5. DRDO also plans test-firing of the Agni-3 and BrahMos missiles in the coming few weeks.
  6. Government sources clarified that the test-firing of the K-4 would be done from an underwater pontoon as the missile is still being tested and launch from a submarine would only be done once it is ready for deployment.
Flashback
  1. K-4 is a nuclear capable Intermediate-range submarine-launched ballistic missile under development by the Defence Research and Development Organisation of India to arm the Arihant-class submarines. The missile has a maximum range of about 3500 km.
  2. The developmental testing of K-4 started in January 2010, when the missile successfully ejected from a pontoon submerged 50 meters below the surface of water and breached the surface.