The photo backdrop to Admiral Sunil Lanba's annual Navy Day press conference on December 3 was a timely one. It showed a submerged Akula class nuclear powered attack submarine, firing a missile. Talks of leasing another Akula-1 class SSN from Russia to replace the INS Chakra at the end of its ten year lease, have reached a crescendo within the Navy in recent weeks.

Last week, a naval delegation led by Inspector General (Nuclear Safety) Vice Admiral Soonil V Bhokare returned after a tour of Russia. They inspected two Akula-1 class submarines, the Bratsk and the Samara, laid up for a deep refit at the Zvezdochka shipyard in the Arctic port of Severodvinsk. The delegation also included a Joint Secretary (Finance) in the MoD discussed the lease of one of these submarines reportedly for USD 3.3 billion (Rs 23,000 crore).



The Indian side is believed to have agreed to this amount and this could be the biggest defence deal after the two countries following the USD 5.4 billion (Rs 40,000 crore) purchase of five S-400 air defence missile systems in October and a USD 1.5 billion deal to buy two Admiral Grigorovich class frigates from Russia.

The naval delegation's visit was followed by a four-day visit to Russia by Admiral Lanba, where he reportedly discussed the Chakra lease and the construction of conventional submarines in India.

The Navy single Akula-2 class submarine, the INS Chakra, was taken on a ten year lease from Russia for USD 2.5 billion in 2011. Officials said the cost of the leasing its replacement, tentatively called the Chakra-3, was worked out after considering a cost escalation using the 2011 lease amount as base price.

Both the Bratsk and the Samara were shipped from a Russian naval base in Kamchatka to Severodvinsk in 2014, rather dramatically as deck cargo on a heavy load carrying merchant vessel. Both submarines were built at the Komsomolsk Shipyard on the Amur River in the Russian Far East and are not exactly new. The Bratsk is a 28-year-old hull while the Samara is 23 years old.

The Navy will soon select one of these hulls to lease. After the Inter Governmental Agreement (IGA) is signed between the two countries, the submarine will be put through an intensive 72-month deep refit and rebuild, where the nuclear reactor will be replaced and a number of indigenous systems installed on board. The INS Chakra in contrast, had a shorter four- year refit between 2004 and 2008 because it did not require a reactor replacement, usually the most challenging part of a nuclear submarine's overhaul.

SSNs use a nuclear reactor for propulsion but are usually armed with conventional weapons like missiles and torpedoes to hunt other warships and submarines and strike at targets on land. Strategic analyst Rear Admiral Raja Menon calls them 'the ultimate arbiters of power', simply for their lethality and versatility. SSNs can be used for multiple tasks like hunting enemy submarines, escorting SSBNs and aircraft carriers and stalking and chasing enemy aircraft carriers and their warship escorts. SSNs differ from nuclear-missile armed SSBNs like the Navy's INS Arihant which completed a deterrent patrol last month. If SSBNs are like bombers, then SSNs are like fighter jets. The plan has five SSNs and is building three more.

All of the Indian Navy's tasks are currently performed by its single platform, the INS Chakra. The submarine was non operational for nearly a year after suffering an accident when some of the panels covering its sonar dome had sheared away while it was doing a high speed underwater run. Admiral Lanba on Monday confirmed that the Chakra had now returned to service. The vessel's ten-year lease expires in January 2022 and it is thus entirely possible that this lease could be extended for another three years to allow for the new submarine.

The Navy's bid for a fresh submarine comes at a time when it is struggling to build six 6,000 tonne indigenous SSNs. At his press conference last December, Admiral Lanba confirmed that the design work on the SSNs had commenced. Last month, however, Admiral Lanba told India Today that the launch of the first indigenous SSN was 'over a decade away', suggesting all is not well.

Naval analysts have taken this long lead time to build the submarine to mean that the Bhabha Atomic Research Centre (BARC) is yet to crack the main piece of the SSN puzzle- developing a nuclear powered reactor. BARC developed an 83 MW reactor with Russian assistance for the Arihant class SSBNs which are meant to quietly lurk out at sea while on patrol. Experts say using this reactor design won't do because of the very high output requirements for an SSN's reactor- rapid starts and very high sustained speeds when in battle.

There is perhaps yet another reason for continued access to the Akula class submarine. At 13,500 tonnes each, the three S-5 class of SSBNS which are soon to start building at the Ship Building Centre in Vizag, are double the displacement of the Arihant class. They have a displacement similar to that of the the Akula-2 class. While the roles of the two submarines are entirely different, the size is the same. At least one source suggests the S-5 is based on the Akula design. The S-5 boats are larger variants of the Arihant class with a larger hull diameter to carry a dozen longer-range SLBMs (the two Arihant class carry can carry four K-4 missiles, the S-4 and S-4*, eight missiles).