Indonesian Navy: Missing Submarine Could Run Out of Oxygen by Weekend

Tria Dianti
Indonesian Navy: Missing Submarine Could Run Out of Oxygen by Weekend In this aerial photo taken from a military aircraft, the Indonesian Navy submarine KRI Alugoro sails during a search for the KRI Nanggala, another submarine that went missing while participating in a training exercise in the waters off Bali, April 22, 2021

Military ships and aircraft were racing against the clock to find an Indonesian submarine missing off Bali with 53 crew aboard who could run out of oxygen by early Saturday, the Navy chief said Thursday.  

The KRI Nanggala-402 lost radio contact about 60 miles (96.5 km) north of Bali during a torpedo firing exercise early Wednesday morning, officials said. 

“In a blackout situation, oxygen on board the KRI Nanggala can only last 72 hours,” Adm. Yudo Margono said at a press conference in Jakarta. 

“It must be found as soon as possible because the oxygen only lasts three days. Calculated since the loss of contact at 3 a.m. [Wednesday], the estimated oxygen capacity is only available until Saturday at 3 a.m.,” he said.  

Meanwhile, President Joko “Jokowi” Widodo said he had ordered military agencies and the coast guard to “mobilize all strengths” in finding the submarine and rescuing its 53 sailors. 

“The main priority is the safety of the 53 crew members,” the president said in a statement.

“To the family of the crew members, I fully understand the feelings of all of you at this time. But, once again, the government will continue to do its best to find and rescue them,” Jokowi said. 

Yudo said search teams equipped with sonar technology had detected a magnetic object underwater at a depth of 50 to 100 meters (164 to 328 feet), but could not determine what it was. 

“The KRI Rigel is being brought in to further observe the object, using a multibeam echo-sounder. Our hope is that it was the KRI Nanggala,” he said, referring to pings detected from the unidentified metal object. 

Earlier in the day, the Navy said the submarine may have sunk as deep as 700 meters (2,296 feet) in the Bali Sea, although it was designed to dive to depths of 250 to 500 meters. 

“Beyond that, it’s dangerous,” naval spokesman Julius Widjojono told reporters, referring to the submarine’s 500-meter-deep limit. 

Yudo said that an oil slick found in several locations could be from a leaked fuel tank, which might have caused a power outage aboard the submarine. 

A second scenario was that the crew jettisoned liquids, including fuel, in the hopes of helping the submarine to resurface, he said. 

Rescue ships from Singapore and Malaysia were on their way to help locate the submarine.


The Indonesian military has deployed dozens of ships and helicopters to scour the sea for the German-built sub. 

Late Wednesday, the Defense Ministry said that aerial surveillance by a helicopter had found an oil spill in the location where the submarine was last detected, but it was not clear if the slick was connected to it. 

Singapore Defense Minister Ng Eng Hen said the city-state had dispatched a submarine rescue vessel, the MV Swift Rescue, with a medical team on Wednesday in response to a request from the Indonesian Navy. 

“The site for search operations, near Bali, is more than 1,500 km [932 miles] away and waters are deep, which is why MV Swift Rescue sailed off as soon as she could,” he wrote in a Facebook post. 

On Thursday, Malaysia sent its MV Mega Bakti – an escape-and-rescue intervention submarine – with 54 crew members to participate in the search for the Indonesian submarine, the Malaysian defense ministry said. 

“Malaysia Defense Minister Ismail Sabri Yaakob has contacted his counterpart in Indonesia, Prabowo Subianto, on Thursday to express his sympathy to the Indonesian Navy and Indonesia for what happened to the KRI Nanggala submarine,” the ministry said in a statement. 

Meanwhile, Australian Foreign Minister Marise Payne said her country was doing what it could to help, but cautioned that Australia operates very different submarines from the one that disappeared. 

“The news of the missing submarine is deeply concerning,” she said in remarks posted on the Australian foreign ministry’s website. 

“There is no question that submarine search and rescue is very complex. But whatever we are able to do, we have undertaken to do. And I think those submariners and their families are very much in need of all of our thoughts and prayers,” she said. 

The Indonesian military has five submarines, including the missing one. 

The Nanggala-402 was built by German company Howaldtswerke-Deutsche Werft in 1977 and came into service in 1981, the Indonesian military said. 

From 2009 to 2012, the submarine was refurbished by South Korea’s Daewoo Shipbuilding & Marine Engineering (DSME), officials said. 

Last month, Daewoo delivered the last of three submarines ordered by the Indonesian military. 

That submarine is the first to be assembled locally in Indonesia by the state-owned shipbuilding company PT PAL, the government said.

Prabowo said the suspected accident underscored the need for the country to modernize its military.  

“We need to renew our armaments. We have not upgraded our armaments because we have been focusing on improving people’s welfare,” he said at a news conference.  

“But this is now urgent and we must modernize our military’s weapons and equipment faster,” he said.  

Putting one’s life on the line was part of serving in the military, the defense chief said. 

“The work of TNI members to safeguard sovereignty is full of challenges and obstacles. Every day is dangerous. I hope all the crew members can be found safely,” said Prabowo, a former soldier. 

Yudo insisted that the Nanggala-402 was in good condition. 

Before it went missing, it fired two torpedoes successfully on an abandoned ship as part of the exercise, he said. 

“The KRI Nanggala was ready for combat,” Yudo said. 

Armed Forces chief Air Marshal Hadi Tjahjanto said the submarine was certified for duty at sea until March 2022. 

“It was ready to conduct operational work,” he said. 

Rescue capabilities  

As a nation that operates submarines as part of its naval fleet, Indonesia needs to acquire underwater search-and-rescue capabilities, according to Iis Gindarsah, a security analyst with Indonesian Laboratory 2025 (LAB 45), a think-tank. 

“Among submarine-operator countries, Indonesia is among those that do not yet have underwater SAR capabilities,” she told BenarNews. 

The Indonesian military recorded 13 naval accidents between 2004 and 2021, while this was the first involving a submarine, she noted. 

“Although no casualties have been recorded, the 13 naval accidents caused material damage classified as heavy,” she said. 

Military and intelligence observer Susaningtyas Kertopati said there still was time to find the submarine and rescue its crew.


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