Contact with the 209/1300-type submarine was reportedly lost around 3 a.m. on Wednesday when it was about 60 miles away from Bali.
"The search for the submarine is still underway," Military Commander, Air Chief Marshal Hadi Tjahjanto, said when contacted from Jakarta on Wednesday.
All vessels equipped with underwater devices have joined the search to locate the missing diesel-electric attack submarine, he informed.
The Indonesian Navy said it lost contact with the submarine, which was officially inducted in 1981, while it was preparing to join a torpedo drill scheduled for Thursday.
The propulsion system of the KRI Nanggala-402, which was built in Germany's Howaldtswerke-Deutsche Werft, uses a Siemens low-speed diesel electric motor, connected directly to the propeller shaft, which generates about five thousand shaft horsepower (shp).
The electrical power is stored in batteries, which make up 25 percent of the weight of the vessel, according to the navy. Four MTU diesel supercharged engines are responsible for generating electricity in the vessel. (INE)
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