German-made vessel had 53 people on board when it lost contact 60 miles north of Bali Submarine may have suffered fuel tank leak due to seawater pressure, Indonesia spokesperson says JAKARTA: Indonesia’s navy has intensified its search for a submarine that went missing with 53 people on board on Wednesday, after an oil spill was detected where the vessel dived, a navy spokesman said. The German-made submarine, KRI Nanggala-402, lost contact 60 miles north off the island of Bali soon after it was cleared to dive at 4 a.m. local time to conduct a torpedo-firing exercise, First Admiral Julius Widjojono told Arab News. The navy deployed a search party involving a number of ships and used a side-scan sonar but failed to locate the vessel, one of five submarines operated by Indonesia. “At 7 a.m., a helicopter spotted an oil spill near the submarine’s dive location,” Widjojono said. Earlier, he said that it was a critical time for rescue as a submarine can be without contact from its base for a maximum of three hours. Based on preliminary assessments, Widjojono said the submarine could have dived 600-700 meters deep — the vessel’s maximum submergence is 250 meters — following a blackout during a static dive. That would have resulted in it becoming uncontrollable and its crew unable to propel it to the surface. The submarine, produced by Howaldtswerke-Deutsche Werft, had been in service with the Indonesian navy since 1981. “With the oil spill spotted near its dive location, there could have been a leak from its fuel tank due to the seawater pressure,” Widjojono said. The country"s defense ministry said in a statement that the navy from several other countries, including Singapore, Australia and India, have offered assistance following the Indonesian navy’s international submarine distress call. The submarine was retrofitted in South Korea in 2009 with a new diesel engine, can travel up to 21.5 knots and is armed with 14 torpedoes. The KRI Nanggala-402 took part in the Cooperation Afloat Readiness and Training joint exercise with the US Navy in 2002 in the Java Sea and Bali Strait, and in a joint Indonesian military exercise in the Indian Ocean in 2004.