Fears Mount Over Missing Indonesian Submarine As Oxygen Runs Low


Tom Hale

Senior Journalist

clockApr 23 2021, 14:46 UTC

The Indonesian submarine KRI Nanggala (402) participates in a photo exercise in 2015. Image credit: US Navy photo by Mass Communication Specialist 3rd Class Alonzo M. Archer/Released

Updated 26/05/2021: Indonesia’s military announced on Sunday that the missing submarine has been found, broken into at least three parts, at the bottom of the Bali Sea. All 53 crew members died in the tragic accident.

Things are looking increasingly desperate for an Indonesian submarine that’s gone missing in waters north of Bali.


KRI Nanggala-402, a 44-year-old submarine of the Indonesian Navy, was carrying out a torpedo drill some 82 kilometers (51 miles) off the coast of Bali in the early hours of Wednesday, April 21, but failed to report back, according to the Indonesian government

“The legendary submarine lost contact shortly after requesting permission to launch the torpedo,” the government said 

A search was launched just before 7 am, three hours after contact was lost. Australia, South Korea, the US, Germany, France, Russia, India, and Turkey have all offered to assist in the search for the submarine, while rescue ships from Singapore and Malaysia are expected to arrive in the area over the weekend, Associated Press reports. 


KRI Nanggala-402 is a 61.3meters-long (201 feet) attack submarine and has 53 personnel on board. Most pressingly, the vessel is quickly running out of oxygen. The submarine has an oxygen supply of 72 hours, meaning it’s set to run out by early Saturday morning. 


Some clues to the submarine’s fate have emerged. Rescue crews are reportedly focusing on an area of the sea that contains an oil slick. Admiral Yudo Margono, the Indonesian Navy’s chief of staff, said oil may have seeped out of a crack in the submarine’s fuel tank or the crew could have intentionally released fuel to reduce the vessel’s weight so it could surface, as per

The Indonesian navy has reportedly detected an object with "strong magnetic resonance" at a depth of 50 to 100 meters (164 to 328 feet), the military said at a press conference on Friday, reports CNN. While they suspect it is the missing submarine, this is yet to be confirmed. An Indonesian warship equipped with high-tech sonar is set to further investigate. 


There are some worries that the submarine may have sunk too deep to reach or recover. According to the Malaysian government, the submarine can operate at depths of up to 257 meters (843 feet). It’s feared that the submarine may have sunk in a particularly deep spot of the otherwise relatively shallow Bali Sea, at a depth of over 600 meters (2,000 feet). Even if the vessel is still intact, it’s likely to be at a depth that’s beyond the capability of most recovery missions. 

"Most rescue systems are really only rated to about 600 meters (1,969 feet)," Frank Owen, secretary of the Submarine Institute of Australia, told AP. "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."

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