The navy has a theory as to what caused a missing submarine to sink as it’s revealed those on board will only have enough oxygen to last until Saturday morning.
Officials reported an oil slick and the smell of diesel fuel near the starting position of its last dive, though there has been no conclusive evidence that they are linked to the submarine.
Indonesia’s navy chief of staff, Admiral Yudo Margono, told reporters on Thursday that oxygen in the submarine would run out by 3am on Saturday.
He said rescuers found an unidentified object with high magnetism in the area and that officials hope it’s the submarine.
There are 53 people on board.
Theory behind submarine's disappearance
Indonesia’s navy said an electrical failure may have occurred during the dive, causing the submarine to lose control and become unable to undertake emergency procedures that would have allowed it to resurface.
It was rehearsing for a missile-firing exercise on Thursday, which was eventually cancelled.
The navy said it believes the submarine sank to a depth of 600-700 meters — much deeper than its collapse depth estimated at 200 meters by a firm that refitted the vessel in 2009-2012.
Ahn Guk-hyeon, an official from South Korea’s Daewoo Shipbuilding and Marine Engineering, said the submarine would collapse if it goes deeper than around 200 meters because of pressure.
He said his company upgraded much of the Indonesian submarine’s internal structures and systems but it lacks the latest information about the vessel.
Australia is assisting in the search for the missing vessel.
Foreign Minister Marise Payne said Australia would "help in any way we can", while Singapore has deployed a submarine rescue vessel to help, the city-state's defence minister said, and Malaysia was also sending a ship.
Australian Strategic Policy Institute senior analyst Marcus Hellyer told News Corp things are looking "very grim".
“If a submarine has an accident at sea, it tends to be catastrophically bad," he said.
Submarine could be too deep to rescue
Frank Owen, secretary of the Submarine Institute of Australia, also said the submarine could be at too great a depth for a rescue team to operate.
“Most rescue systems are really only rated to about 600 meters,” he said.
“They can go deeper than that because they will have a safety margin built into the design, but the pumps and other systems that are associated with that may not have the capacity to operate. So they can survive at that depth, but not necessarily operate.”
Mr Owen, a former submariner who developed an Australian submarine rescue system, said the Indonesian vessel was not fitted with a rescue seat around an escape hatch designed for underwater rescues.
He added a rescue submarine would make a waterproof connection to a disabled submarine with a so-called skirt fitted over the rescue seat so that the hatch can be opened without the disabled submarine filling with water.
Mr Owen said the submarine could be recovered from 500 meters without any damage but couldn’t say if it would have imploded at 700 meters.
with The Associated Press and Reuters
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