Chris Barrett and Karuni Rompies, Singapore – Two life rafts from a lost Indonesian submarine have been retrieved from the floor of the ocean near Bali but the China-led recovery operation has not been able to find the bodies of any of the 53 men who were aboard.
There were no survivors when the 40-year-old KRI Nanggala 402 sub sunk to a depth of 838 metres during a training exercise on April 21 and was later found by an underwater robot broken into several pieces.
But as an Indonesian navy investigation continues into the submarine's demise, the international effort to salvage the wreckage is continuing.
China is heading the mission in the Lombok Strait after proposing to do it for free – an offer met with scepticism by some regional observers.
Two life rafts weighing 700 kilograms each had been pulled out of the ocean, Indonesian navy second fleet commander Rear Admiral Iwan Isnurwanto said on Tuesday.
A mud-covered crater with a diameter of 38 metres and a depth of 10 to 15 metres has also been found by the Tan Suo Er Hao scientific research ship and its deep-sea submersible vessels.
But the search has not yet been able to locate the pressure hull or main body of the submarine. While the recovery team is still trying to remove the bow and stern sections, it has given up on pulling out the 20-tonne bridge as it was deemed too heavy.
There has been no sign of the bodies of any of the 49 crew, three gunners and the commander who were aboard the Nanggala and the recovery team predicts the main section of the submarine may be in the crater.
"We have not found the body of the vessel," Iwan said. "We only guess its position is perhaps in there. It can be buried in the mud but until now the sonar beam cannot detect [anything]."
The crater on the bottom of the ocean poses serious challenges for the salvage mission.
"Whether the personnel are there or not, maybe [they were]," Iwan said, vowing to continue the mission until they found the body of the vessel.
Iwan said that if there had been a blackout on the submarine, the 1300-tonne vessel would have plummeted to the ocean floor in no more than 90 seconds and cracked open when it was between 300 metres and 400 metres beneath the surface. "Our hope is that the personnel die as martyrs," he said.
What began as a desperate mission to find and rescue the crew before oxygen ran out became a salvage mission four days after the submarine sank, when sonar detected the wreckage on the seabed, including a bright orange escape suit that was floating underwater.
The Australian navy took part in the multinational search effort alongside the United States, India, Singapore and Malaysia when the Nanggala vanished last month, sending two ships to assist Indonesia.
Australia also said it would help in the recovery operation, as did the US, but it was China's offer that was accepted.
The Indonesian navy has said that a strong underwater wave might have been responsible for sinking the Nanggala, which was one of the country's five submarines, but it is continuing a probe into the cause of the maritime disaster.
South-east Asia's most-populous country has sought to revamp its military capability, yet some equipment is still old and there have been fatal accidents in recent years.
Indonesia had five submarines before the latest accident: two German-built Type 209s including Nanggala and three newer South Korean vessels.