Hopes of rescuing dozens aboard a missing Indonesian submarine are fading as its oxygen reserves are believed to have run out, turning the focus to retrieving the stricken vessel from waters off Bali.
As hundreds of military personnel took part in a frantic hunt for the KRI Nanggala 402, authorities said the German-built craft was equipped with enough oxygen for three days after losing power.
That deadline passed early on Saturday with still no sign of the missing vessel and its 53 crew.
Search helicopters and ships had left Bali and a naval base in Java heading to the area on Friday where contact was lost with the 44-year-old vessel on Wednesday as it prepared to conduct a torpedo drill, with the head of the Indonesian submarine fleet aboard.
An American reconnaissance plane, P-8 Poseidon, landed early on Saturday to join the search, along with 20 Indonesian ships, a sonar-equipped Australian warship and four Indonesian aircraft.
Singaporean rescue ships were also expected on Saturday, while Malaysian rescue vessels were due to arrive Sunday.
“So far we haven’t found it … but with the equipment available we should be able to find the location,” Achmad Riad, a spokesman for the Indonesian military, told a news conference on Friday.
An air force pilot said six tonnes of equipment had been flown to a base to help with the search, including underwater balloons to help lift a vessel.
The navy said it was investigating whether the submarine lost power during a dive and could not carry out emergency procedures as it descended to a depth of 600-700 metres, well beyond its survivable limits.
An object with “high magnetic force” had been spotted “floating” at a depth of 50-100 metres, the Indonesian navy chief of staff, Yudo Margono, said, and an aerial search had spotted an oil spill near the submarine’s last location.
The diesel-electric powered submarine could withstand a depth of up to 500 metres but anything more could be fatal, a navy spokesperson, Julius Widjojono, said. The Bali Sea can reach depths of more than 1,500 metres.
“If the submarine is in a 700-metre sea trough, it will be difficult for them to survive because underwater pressure will cause cracks and ruptures of the steel hull,” defence expert Connie Rahakundini Bakrie said.
The submarine joined the Indonesian fleet in 1981, the defence ministry said, and underwent a refit in South Korea that was completed in 2012. It was said to be in good condition.
“I hope they will be found alive,” said Berda Asmara, the wife of crew member Guntur Ari Prasetyo, 39, who has sailed on the Nanggala for 10 years. “We had a video call. He told me that he would go sailing and asked me to pray for him,” she said of the last time they spoke.
“I haven’t received any update yet, [the] rescue is still underway. I am praying that there will be a miracle for my husband and other Nanggala crew,” said Ekhan Retno Asih Primadani, the wife of lieutenant commander Eko Firmanto.
Australia, India, Malaysia, Singapore and the US have sent specialised ships and aircraft in response to Indonesian requests for assistance. The US military is sending a P-8 Poseidon aircraft to assist in the submarine search.
On Friday, the Pentagon said US defence secretary, Lloyd Austin, had spoken to his Indonesian counterpart and offered additional support, which could include undersea search assets.
The White House national security adviser, Jake Sullivan, told the Indonesian foreign minister, Retno Marsudi, on Thursday the “United States would do everything possible to support Indonesia’s search and rescue effort”, a spokesperson said.