Indian Navy is understood to have sought the assistance of Dutch company SMIT for salvaging INS Sindhurakshak — the Kilo-class submarine that sunk in the Mumbai harbour on Wednesday — as it has shown signs of a rupture with water ingress despite multiple pumps employed at the Naval dockyard.
Experts from the Singapore office of SMIT, one of the largest companies worldwide for emergency maritime response, are expected to be at the accident site by Friday.
SMIT along with another Dutch firm Mammoet, had salvaged Russian nuclear submarine Kursk after it exploded and sank in the Barents Sea in August 2000 with its 118-member crew and nuclear warheads on board.
The navy had earlier sought the help of a Singapore-based firm to recover INS Vindhyagiri that sank in January 2011 after colliding with a merchant vessel off the Mumbai coast.
“It looks unlikely that we will be able to ‘dewater’ some compartments on Sindhurakshak. For that, they need to be made watertight first, which may not be possible due to the extensive damage the sub has suffered,” a senior navy official said.
Navy chief Admiral DK Joshi is expected to submit a detailed report on the accident to defence minister AK Antony by Friday evening, who will then possibly make a statement in Parliament on Monday.
Top government sources said naval divers were able to open the upper and lower hatches of the conning tower as well as the forward hatch of the submarine, but they were not able to pump out water from the vessel.
“This could be due to a rupture in the hull because of the explosions or there was sea water ingress through open pipes. Another inexplicable event was that the conning tower hatch was fused due to heat. This hatch is always kept open when the boat is in harbour,” said a senior navy officer.
While the reasons for the disaster are still unclear as the submarine batteries were replaced three days before the accident, the needle of suspicion is on the armament with either a booster charge or a pyro cartridge exploding in the close confines of the vessel.