by G Hari Kumar

In early 2017 the first indigenously designed and built nuclear powered submarine, the INS Arihant finally completed another round of tests and was declared in service. Shortly thereafter parts of the sub were flooded because, as the navy put it, someone left a hatch open (or failed to close it properly) and seawater got into the boat. It was reported that ten months of repairs were required to deal with the salt water damage. It is unclear if the Arihant is back in service, or ever will be.

This comes after three decades of planning, numerous revisions and technical failures, construction and delays in getting all systems functioning at the same time. It started when India began working on a highly secretive SSN (nuclear attack sub) called the Advanced Technology Vessel project in the late 1980s but as work progressed it was decided to enlarge SSN design by adding a ballistic missile compartment and put all their efforts into creating an SSBN. This was a tried and true solution. Russia and China had successfully done this, following the example of the United States in the 1950s.

Arihant was supposed to enter service before the end of 2015 but there were more unforeseen technical problems to fix. Nevertheless, Arihant was commissioned as a navy ship in August 2016 even though it had not carried out its sea trials. These commenced in late 2016 and were declared successful. Apparently Arihant has yet to carry out a “combat cruise” (with nuclear armed missiles) to within range of potential enemy targets.

Arihant was launched in 2009 but completing the sub was delayed again and again because of new problems showing up as building a nuke submarine is a complex exercise. Nevertheless the success of Arihant led to an SSN (nuclear attack submarine) program, which is now under way. In 2015 India announced ambitious plans to build six SSNs but admits development and building will probably take at least fifteen years. One locally made nuclear sub doesn't change the balance of naval power much for India, which is already dominant in the Indian Ocean region but it does show that India can build nuclear subs and six SSNs will make a difference. Two more Arihants are under construction and two more planned.

Meanwhile in March 2016 DRDO successfully tested its new K-4 SLBM (Submarine Launched Ballistic Missile) under realistic conditions. This consisted of a submerged pontoon (like the one used in a submarine) that successfully released the missile at a realistic depth. The missile reached the surface, ignited its rocket motor and completed its ballistic flight as it was designed to do. Several more successful tests like this are required before K-4 can enter service. K-4 is based on the Agni 3 land based ballistic missile, which has been in service since 2010. Both the Agni 3 and K-4 have a range of 3,500 km. K-4 is a 20 ton, two stage, solid fuel missile that carries a one ton warhead.

Arihant was built to carry nuclear armed K-4 or K-15 ballistic missiles designed and manufactured in India. Arihant has four vertical launch tubes, which can carry twelve (three per launch tune) of the smaller K-15 missiles or four larger K-4s. The Arihant is based on the Russian Charlie II sub, which it resembles. The Charlie class had eight launch tubes, outside the pressure hull, for anti-ship missiles. Arihant has a crew of 90-100 and six 533 mm (21 inch) torpedo tubes in addition to the four vertical missile launch tubes.

In early 2013 the K-15 missile underwent its final development test and was ready to be installed in the Arihant. This came after five years of testing and tweaking. In 2007, India announced that it had perfected the technology for launching ballistic missiles from a submerged submarine. That meant the submerged pontoon design had been perfected as well. In 2008, India began a series of twelve test firings from a missile cell designed to fit into the Arihant. These test firings were not done from the Arihant but from the cell placed in the ground or underwater to simulate launch from the sub. Seven launches took place in 2008.

The seven ton K-15 has a 700 km range with a one ton warhead or 1,900 km with a 189 kg warhead. The latter weight is sufficient to handle a nuclear warhead if India has been successful in developing warhead technology to the same point the U.S. and Russia were in the 1980s.

There are apparently problems with the readiness of the nuclear warheads used in the Arihant SSBNs. This has to do with security and controls over who has launch authority. This subject has not become a news item yet but it is another reason why the Arihant is not really “in service.” (Adapted report from SP)

Hari is a historian, author, thinker, military enthusiast, cyber geek and an incurable patriot. Views expressed are of the author and do not necessarily reflect the views of IDN. IDN does not assume any responsibility or liability for the same