The Indian Navy and the Defence Ministry on Tuesday maintained silence on induction of its first nuclear submarine Arihant in the force, even as sources indicated the vessel has been inducted.The submarine, the lead ship of India's Arihant-class of nuclear-powered ballistic missile submarines, has been designed based on the Russian Akula-1 class submarines.Neither Defence Ministry officials, nor the Indian Navy confirmed or denied the media reports on induction of the vessel.Asked about the submarine at a function here, Controller of Warship Production & Acquisition in Indian Navy Vice Admiral G.S. Pabby refused to answer the question.The Vice Admiral, however, said that an interaction will soon be held to answer all questions on the submarine."There will soon be an opportunity to talk about it," Pabby said.Asked about the induction, officials refused to comment on or off record.However, they indicated that the boat is now part of the Indian Naval fleet, but did not divulge an exact date of induction. Asked about the possible reasons for the secrecy, former Navy chief Admiral Arun Prakash (retired) said the secrecy around the induction of the vessel, being a nuclear submarine, was "customary"."Arihant is an achievement technology wise, but otherwise it is a top secret," Admiral Prakash told IANS."Its mission is to be a nuclear deterrent. Everything to do with the submarine will be a secret. Its movement, position and location will not even be known to the Navy," he said.
"It is not a normal ship, though we would like to show it off, we cannot," he added.The 60,000-tonne submarine was also not included in the International Fleet Review (IFR) hosted by the Indian Navy earlier this year.INS Arihant is India's first indigenous nuclear submarine, and the lead ship of the Arihant-class of nuclear-powered ballistic missile submarines, which was launched in 2009.While it was initially expected to go on sea trials by 2012, it went into sea trials only in December last year. The sailing for the sub has not been smooth, as in 2013 the miniaturised nuclear reactor of Arihant, built with Russian help, had gone critical.The submarine completes India's nuclear triad giving it the capability to respond to nuclear strikes from sea, land and air-based systems.The project was under Advanced Technology Vessel programme under the supervision of the Prime Minister's Office and involving agencies and establishments such as the DRDO, the Department of Atomic Energy, the Submarine Design Group of the Directorate of Naval Design, besides companies such as L&T.Its 100-member crew has been trained by Russian specialists, Indian scientists at Bhabha Atomic Research Centre have received significant expertise in reducing the size of the reactor to help it fit into the 10 m diameter hull of the nuclear submarine. India currently operates Russian-origin nuclear-powered submarine INS Chakra, which it leased for 10 years from Russia in 2012.Nuclear submarines have capability to stay out in the sea for longer, and don't need to surface for a long duration.