INS Kalvari is part of a USD 3.5 billion contract signed by the defence ministry with French firm DCNS.
Kalvari, Indian Navy's first indigenous Scorpene-class stealth submarine, will hit the waters again in September for its final phase of sea trials ahead of its planned induction by the end of this year.
The 66-metre-long INS Kalvari is part of an over USD 3.5 billion contract signed by the defence ministry with French firm DCNS in October 2005 to jointly develop six submarines.
Under Project 75 of the Indian Navy, the submarines are being built at the MDL dockyard in Mumbai under license from DCNS.
While the first four are conventional submarines, the last two are to be equipped with the Air Independent Propulsion (AIP) system, which will enable the vessel to stay underwater for longer.
However, sources indicate that the AIP technology might be delayed.
Interestingly, the submarines still do not have its main weapon -- the heavy weight torpedos.
The original torpedo selected for the submarine was the one manufactured by one of the subsidiaries of scam-tainted firm Finmeccanica.
The government has decided to withdraw the tender for the heavy weight torpedos and go in for an alternative.
Once INS Kalvari is handed over to the Navy, the plan is to have other five inducted every nine months.
Construction of the first submarine started on 23 May 2009. The project is running four years behind schedule.
The government plans to go in for a follow-on order of three more Scorpene class submarines.