Indonesian Navy: Salvaging Sunken Sub a Challenging Task
2021-05-04 -- Underwater waves and the presence of live torpedoes could complicate attempts to salvage the wreck of an Indonesian military submarine that sank off Bali last month with 53 sailors onboard, Navy officials said Tuesday.
Three Chinese naval ships and an Indonesian ship will take part in efforts to lift pieces of the broken submarine, the KRI Nanngala-402, from a depth of 838 meters (2,749 feet), Indonesia's Navy said. Ships and aircraft from several other nations had helped in the frantic search for the sunken sub in late April.
One of the three People's Liberation Army Navy (PLAN) ships, the Yongxing Dao-863, likely will be the first to be deployed to attempt to bring pieces of the submarine to the surface, said Rear Adm. Muhammad Ali, an assistant to the navy chief of staff.
An attempt to raise the wreckage carries high risks even though the Chinese Navy ships can each lift a load of up to 2,000 tons, Ali said. The Bali seabed features steep slopes with a maximum depth of 1,590 meters (5,215 feet).
"Lifting it is a bit difficult because attaching the hook to the object to be lifted can only be done manually, either by a diver or a robot. Divers have to wear special suits to get to such a depth and this is difficult," Ali told reporters during a news conference in Jakarta.
"There is also an internal solitary wave. We've said the other day that this phenomenon could happen, so we really need to be careful and have to be patient," he said, adding it was possible to retrieve smaller pieces first before getting to the three major sections.
Ali, a former commander of the Nanggala-402, said in a statement last week that a powerful underwater current, known as an oceanic nonlinear internal solitary wave, might have dragged the submarine down and caused it to sink.
Col. Djawara Whimbo, a spokesman for the Indonesian military, said the Chinese ships were well-equipped to carry out the salvage operation.
"Offers of assistance came from many countries, but China is the closest and the most qualified," Whimbo told BenarNews, an RFA-affiliated online news service.
The Yongxing Dao-863 has a mini submarine that can carry divers and is equipped with an underwater robot, side-scan sonar, multibeam echo sounder and medical equipment, Ali said. The mini-sub can dive to more than 1,000 meters (3,281 feet).
The Yongxing Dao-863 and the Nantuo-195, a Chinese ocean tugboat, reached Bali Sea waters on Sunday. The third PLAN ship, the Tan Suo 2, a scientific salvage vessel, was expected to arrive later on Tuesday, officials said.
Several Indonesian warships were on standby as a precautionary measure because the sunken submarine carried live torpedo warheads, Navy spokesman 1st Adm. Julius Widjojono said.
"Everything will be done with careful calculations," Julius said. "The torpedoes only explode on impact. If there's no impact, they won't explode."
Previously, Ali had said that the Nanggala-402 carried three torpedoes even though it was capable of carrying up to eight, each weighing nearly two tons.
Foreign ships gone
The German-made KRI Nanggala-402 was taking part in a torpedo-firing exercise off the northern coast of Bali when it lost contact as it was about to receive clearance to fire on April 21. All 53 crew members are presumed dead.
The submarine, which weighed up to 1,395 tons and was 59.5 meters (195 feet) long, was found broken into at least three pieces on April 25 on the seabed after a search effort involving ships and aircraft from Singapore, Australia, Malaysia, India and the United States. The ships and aircraft from those countries have now departed the area, military officials said.
The ships from the other countries did not have adequate equipment to take part in the salvage phase, Julius said.
"Their missions were completed with the discovery of the Nanggala-402 wreckage," he said.
The Indonesian Navy said it had enlisted an oil rig ship through SKK Migas, the country's oil industry regulator, to try to recover the sunken submarine.
The agency was hammering out technical details before launching the salvage operation with the Timas 1201, which is equipped with a crane that can lift loads of up to 1,200 tons, SKK Migas chief Dwi Soetjipto said Monday.
China's involvement in the salvage operation is part of Beijing's quest to exert power amid tensions in the South China Sea, according to Aristyo Rizka Darmawan, a senior researcher at the Center for Sustainable Ocean Policy at the University of Indonesia.
"We will see if this is sincere or there is a hidden agenda. It doesn't come with explicit strings attached," Aristyo told BenarNews.
China's assistance, he said, was unlikely to sway Indonesia's position on the North Natuna Sea in the southern reaches of the South China to which Beijing claims historic rights.
"I think Indonesia will remain firm and will stand by its position in accordance with international law," Aristyo said.
While Indonesia does not regard itself as a party to territorial disputes over the South China Sea among several governments, Beijing claims historic rights to parts of the maritime region that overlap Indonesia's exclusive economic zone (EEZ).
Indonesia has had several stand-offs with China over allegations that Chinese fishing boats, escorted by China Coast Guard ships, operated in its EEZ off the Natuna Islands.
Meanwhile, the governments of Brunei, Malaysia, the Philippines, Taiwan and Vietnam have territorial disputes with China, which claims nearly all of the South China Sea as its own.
However, Muhammad Arif, an international relations analyst at the University of Indonesia, said the PLAN's involvement in recovery efforts should be seen in a positive light.
"For Indonesia and China, this can be an opportunity to show that China's growing maritime power can contribute positively to the region," he told BenarNews.
He noted that Indonesia had welcomed help from other countries, including the United States and Australia.
"Indonesia is not aligning with any power. What is clear is that anyone who can help, anyone who has the capability to help, has been involved," he said.
Reported by BenarNews, an RFA-affiliated online news service.
|Join the GlobalSecurity.org mailing list|