The submarine, KRI Nanggala 402, disappeared during military drills off the resort island of Bali. Despite international efforts to locate it, the only traces that have been found are an oil spill, along with some minor debris believed to have originated from the vessel.
“With the authentic evidence we found believed to be from the submarine, we have now moved from the ‘sub miss’ phase to ‘sub sunk,’” Navy Chief Yudo Margono said during a press conference on Saturday.
Earlier, Indonesian officials said that the submarine had enough oxygen reserves to survive underwater until at least early on Saturday. While the navy refrained from making any statements on the fate of the crew, the debris recovered – a bottle of periscope grease and parts of a torpedo launcher – suggests the submarine had been crushed.
“We don’t know about the victims’ condition because we haven’t found any of them. So we can’t speculate,” Margono stated. “But with the [discovery] of these items, you can make your own conclusion.”
The submarine disappeared during a dive, going to a depth of over 600 meters (around 2,000 feet). Its depth made recovery impossible, Indonesian officials said earlier this week.
The cause of the sinking remains unknown, with the navy suggesting an electrical failure might have led to the vessel’s demise. The submarine presumably lost its buoyancy and was unable to resurface.
The KRI Nanggala 402 was a 44-year-old vessel, belonging to the German Type 209 family of diesel-electric attack submarines. The depth at which the vessel is believed to have found itself is well beyond its crush mark, as these submarines were tested for diving to only 500 meters (1,600 feet).
Even if the submarine had not sunk to that extreme depth, rescuing people on board would likely have been impossible. The old vessel did not feature a lot of safety instruments, such as an emergency docking collar, that would allow a submersible to dock with the crippled submarine and rescue its crew.