BO5 / K-15 / Sagarika / Shourya

The Indian Navy joined the nuclear triad club after operationalizing its first submarine-launched ballistic missile and testing it in August 2018. The New Indian Express, citing unnamed defense official, reported that the ‘Sagarika’ SLBM (referred to as B-05 in the report) was tested from aboard the INS Arihant nuclear-powered ballistic missile submarine which was commissioned in 2016. The test took place off the coast of Vizag on August 11 and 12 and saw the submarine launch a total of three missiles. All three missiles were fired from the submarine, positioned nearly 20-meter deep in the sea. Officials deemed the test a success. The Indian Navy’s Sagarika SLBM has a range of about 700 km and can carry a 1,000 kg warhead. Unarmed test versions of the missile were previously launched by INS Arihant in 2015 and in 2016.

The tests also confirmed the successful induction of INS Arihant submarine. The 111-meter long, 15-meter tall and 11-meter broad submarine is capable of carrying six torpedoes of 533 mm and 12 B-05 missiles or four K-4 missiles.

The K-15 (B-05) tests will pave the way for an early induction of 3,500-km range K-4 missile, which is under developmental trials. Apart from the cruise variants of B-05 and K-4 missiles, DRDO is also developing 5,000-km range K-5 and 6,000-km range K-6 which would add more teeth to the arsenal.

This missile, whose name has been variously given as Sagarika or at times K-15 or even Dhanush, has finally been christened as BO5 - a medium-range ballistic missile. While published reports are generally consistent about the characteristics and chronology of this system, there was for a long time general disagreement on one fundamental point, whether the missile is a ballistic missile or a cruise missile. The reported physical dimensions of the missile seemed to support the reporting that it is a cruise missile. Sagarika appeared to be the designation of the sea-based version of the missile which is designated Shourya when deployed on a land-based Transporter Erector Launcher.

The K-15 launch sile is well attested, and appeared to be intended for the Advanced Tehnology Vessel nuclear submarine. It is, however, far too large for the Sagarika missile. It is reasonable to believe that this launcher would initially be employed with 3 BO5 - a medium-range ballistic missile in each tube, which could subsequently be back-fitted with a single Agni-III ballistic missile.

Started in the early 1990s, DRDO was reported to have developed a 300-km submarine-launched ballistic missile, Sagarika, based on the Prithvi. The program is reported to have started in 1992 and was originally reported to involve adapting a ramjet engine to the missile to reduce the need for heavy oxidizers. In 1994 the periodical Flight International reported that India's Aeronautical Development Establishment (ADE) had for the past two years been engaged in designing a ramjet-powered, submarine-launched missile dubbed the Sagarika. Other reports state that Sagarika was initially designed as a solid-fuelled version of the Prithvi. But the idea was shelved after the navy indicated its preference for a cruise missile. India did not have a submarine configured for launching ballistic missiles.

Something about the Sagarika inspired a cloak of secrecy. In October 2005 it was reported that India was developing the Sagarika, said to be a submarine-launched cruise missile with a range of about 300 km. In 2005 defence minister Pranab Mukherjee confirmed the program: "This is a DRDO project but we would not like to make a premature advertisement." Later, in Parliament, he denied the project even existed. As late as 2006 one observer suggested that the Sagarika was merely a figment of the Non-Proliferation community's imagination. Defence Minister Shri Pranab Mukherjee in a written reply to Dr Vijay Mallya in Rajya Sabha stated 02-August, 2006 that "There is no missile project by name “Sagarika”."

In April 2007 it was reported that the indigenously-built Sagarika cruise missile, with a range of nearly 1,000 km and a 500-kg warhead, had two variants capable of being launched from aircraft and submarines. Sagarika was said to be the primary armament for the long-delayed Advanced Technology Vessel indigenous nuclear submarine, and the IAF was said to be considering equipping the forthcoming Medium Transport Aircraft with the stand-off missile. And in June 2007 it was reported that DRDO was currently working on the Sagarika submarine launched cruise missile. The nuclear capable Sagarika was said to have the capability to carry a 500 kg warhead over a distance of 1,000 km. It is also planned to develop an air launched version of Sagarika.

In April 2007 India conducted a test of the Sagarika from a submersible pontoon launcher. In July 2007 it was reported that India's Defense Research and Development Organization (DRDO) had started work on three new types of missiles: a superior version of the Agni III, a hypersonic BrahMos and a naval missile known as Sagarika. The Sagarika would be a submarine launched, nuclear-armed, missile with a range of 1000 kilometers.

On 27 February 2008 India proved that it had the capability to launch missiles from underwater by successfully test-firing the Sagarika missile from a pontoon off the coast of Visakhapatnam. The pontoon simulated the conditions of a submarine. Shortly after noon, the missile's booster ignited and Sagarika rose from the pontoon. It impacted the sea over 700 km away. A Defence Research and Development Organisation (DRDO) missile technologist said "It has been consistently successful. This is not the first time that we have launched the missile. We have done it earlier a few times although it went by different names."

This test, the sixth test of the 700-km range Sagarika missile, completed its goal of having air, land and sea ballistic systems, the defence ministry said. The launch from a submerged pontoon took place off India's southeast coast near the port city of Visakhapatnam around 1:00 pm (0730 GMT), a defence ministry spokesman said. With the latest test, India joins an elite group - the United States, Russia, France and China - that has such ability. The test came two months after India's chief military scientist M. Natarajan said New Delhi would test a ballistic missile with a range of 6,000 kilometers in 2008.

The tactical, submarine-to-surface missile was said to be a light, miniaturised system, which was about 6.5 meters long and weighed seven tons. Powered by solid propellants, it was reported to be able to carry a payload of about 500 kg and can be launched from different platforms - from the ground, from underwater and mobile launchers. Other reports said the missile was powered by a turbojet, could carry a 500-kg payload, and was 8.5 metres long and about a metre in diameter. Ultimately, it would be launched from the indigenous nuclear powered submarine under construction at Kalpalrkam in Tamil Nadu and Visakhapatnam. The missile can carry both nuclear and conventional warheads.

Sagarika was developed at the DRDOs missile complex in Hyderabad. The complex consists of the Defence Research and Development Laboratory (DRDL), the Advanced Systems Laboratory (ASL) and the Research Center, Imarat (RCI). The missile was designed and developed by the DRDL, the ASL provided the motors and propulsion systems. The RCI's contribution was in avionics, including control and guidance systems and inertial navigation systems.

In July 2008 DDRO was reported to be near breakthrough in test firing the country's first underwater launch ballistic missile, Sagarika. Sagarika had already been test-fired from a pontoon, but now DRDO is planning a full-fledged test of the missile from a submarine and for this purpose may use the services of a Russian Amur class submarine.