India successfully tests intermediate-range ballistic missile launched by submarine

Ankit Panda, The Diplomat
10 April 2016

India’s Defense Research and Development Organization (DRDO) has once again test-fired the K-4 nuclear-capable submarine-launched ballistic missile (SLBM)–this time from aboard the Indian Navy’s indigenously built nuclear submarine, the INS Arihant, the first submarine in its class. According to press reports citing DRDO officials, the test was “highly successful” and involved a fully operationally configured K-4 with a dummy payload. In March 2016, DRDO had successfully tested the K-4 from a submerged platform in the Bay of Bengal; DRDO officials at the time declared the test to have been a “roaring success.”
According to the New Indian Express, the Arihant-based K-4 test was “conducted on March 31 nearly 45 nautical miles away from Vishakhapatnam coast in Andhra Pradesh.” The K-4 missile was fired from the Arihant‘s onboard SLBM silos.
India’s K-4 is an intermediate-range, nuclear-capable, submarine-launched ballistic missile. Though official details remain scarce given the project’s sensitivity, most estimates place the K-4′s range at roughly 3,500 kilometers. Recent testing of the K-4 has sought to test the full operational range of the missile. As my colleague Franz-Stefan Gady discussed in March, “the K-4 was only tested to a range of 3,000 kilometers” in previous testing. In addition to its range, recent testing as sought to test the SLBM’s accuracy. Claims by DRDO scientists and publicly available information on the system suggest that the K-4 is a highly accurate system. As Franz has discussed, DRDO scientists have boasted that the K-4 has “near zero circular error probability” and uses “a Ringer Laser Gyro Inertial navigation system.”
The K-4, along with the K-15 Sagarika SLBM, will give the Arihant-class of nuclear submarines their nuclear strike capabilities, allowing India to field an undersea nuclear deterrent capability. The K-15 has a considerably shorter range than the K-4. At a maximum strike range of approximately 750 kilometers, Arihant-class submarines would have to move close to enemy shores to successfully deploy the K-15 SLBMs, increasing the odds of detection. The intermediate-range K-4 helps rectify this shortcoming. The K-4 is capable of carrying both
conventional and nuclear payloads in excess of 2,000 kilograms.
The Indian Navy anticipates commissioning the first Arihant-class submarine in 2016. The Indian Navy anticipates eventually fielding a force of three to six Arihant-class submarines. INS Aridhaman, in construction, will be the second submarine of the Arihant-class. Each submarine will be able to carry 12 K-5 Sagarika missiles and 4 K-4 SLBMs. With the Arihant‘s commissioning, the Indian Navy will join the navies of the United States, the United Kingdom, France, Russia, and China in operating nuclear-powered ballistic missile submarines.