The last contact came on Wednesday at 3 in the morning. Then the Indonesian navy’s submarine disappeared, somewhere deep in the dark waters of the island of Bali in the Pacific Ocean.
By evening, the Indonesian Ministry of Defense had detected only one possible sign of the missing ship carrying 53 people on board: a large oil tanker found in the area where the submarine began diving north of Bali.
The oil spill could be evidence of the submarine’s suffering from a crack in the ship’s hull, said first-admitted Julius Widjojono, a spokesman for the Indonesian navy. Such a crack is extremely unusual, but can occur with a sudden change in pressure, naval experts said.
The last request made by the submarine, known as KRI Nanggala-402, was to have permission to descend into a deeper part of the Bali Sea to launch torpedoes for naval exercises, said First Admiral Widjojono. The area includes valleys that are at least 1,900 to 2,300 feet (or about 600 to 700 meters) deep.
The request was accepted, but contact with the submarine was lost afterwards.
Built in 1977 in Germany and reassembled in 2012, Nanggala was “fully maintained” in May 2018, according to a defense expert who did not want to be identified when talking about internal naval information.
The submarine, about 196 feet long and over 19 feet wide, was built to accommodate 34 crew members, according to the specifications quoted by the navy during a previous training session. It is not clear why the ship had more people on board during this torpedo exercise.
“The quality of the navy crew is not in doubt, but it may be necessary to re-examine the treatment of this submarine,” said Connie Rahakundini Bakrie, a military analyst at the University of Indonesia. “I’m afraid there is a lack of standard maintenance of the operating procedure.”
Two Indonesian naval vessels are using sonar to search for the missing ship, said First Admiral Widjojono. One of the ships was deployed earlier this year to search for the flight recorders of an Indonesian plane that crashed in January.
Armies in neighboring countries, such as Australia and Singapore, have been alerted and will join the search in the coming days, Indonesia’s Defense Ministry said.
A country with thousands of inhabited islands, Indonesia is the largest archipelago nation in the world. Its navy is poorly funded, even though the country has to face regular incursions by foreign fishing fleets and coastguards.
Underwater accidents are rare. In 2000, a Russian Navy submarine sank on the seabed after an explosion on board. All 118 people died after rescue teams needed days to gain access to the submarine, and oxygen was depleted for the 23 sailors who survived the blast.
In 2017, an Argentine Navy submarine disappeared with 44 people on board, after what was believed to be an electrical failure. His wreck was found a year later.
But miraculous rescues took place. In 2005, seven sailors aboard a small Russian Navy submarine caught in a fishing net were released just hours before their oxygen was depleted.
“I will cross my fingers helping Australian and other countries,” said Bakrie, an Indonesian military analyst, referring to the search for the missing Indonesian submarine. “I cross my fingers for the crew to survive.”