Why is INS Sindhurakshak such a big loss? 10 things you need to know

 The accident aboard the INS Sindhurakshak has brought back the focus on the submarine fleet of the Indian Navy which has suffered a hit with the sinking of the vessel. Here are some facts about the INS Sindhurakshak and  the Kilo class submarines that the Indian Navy operates: - The Kilo class of submarine is one of the quietest diesel submarines in the world and can dive upto a maximum depth of 300 metres while staying underwater for upto 45 days, says this detailed profile of the submarine on FAS.org. - The submarine can carry upto 16 missiles, 18 torpedoes and 24 sea mines - The submarine apparently has a high chance of survival even if there is a hole in it. Navy chief Admiral DK Joshi had pointed out that they could salvage the submarine if they can pump in air into it. - Russia had exported 10 of the Kilo class submarines to India out of the 21 submarines that it had exported - It is the seventh and the last of the 10-kilo class submarines that India bought from Russia between 1986 and 2000 to have undergone mid-term repairs and modernisation in Russia. Of the three remaining submarines, one was repaired in India and the others are still under repair. [caption id=“attachment_1045855” align=“alignleft” width=“380”]  Navy personnel at the site of the incident. AFP[/caption] - $80 million was spent on the upgradation of the INS Sindhurakshak In August 2010, INS Sindhurakshak arrived at Zvezdochka shipyard in Severodvinsk (Russia) for an overhaul and upgrade. It came off the slips at shipyard in on 23 June 2012, marking the completion of a mid-life refit programme. - The submarine has been modernized and repaired and its sea trials started earlier in October 2012. The upgrade includes improved electronic warfare systems,control systems, and integrated weapon control system. This modernization enables incorporation of new Russian missile system Club-S with 200-km cruise missile range, Indian sonar USHUS and radio communication systems CCS-MK. -Advisors from Russia are expected to supervise the modernisation program of the three other Kilo class submarines in the Indian Navy fleet which will take place in Vishakapatnam - Russia has also offered a second modernisation program which it claims can add anywhere between 5 to 10 years of additional life to the ageing submarine fleet, which it claims could be most cost effective