The hunt for a missing Indonesian submarine with 53 crew onboard has reached a critical phase as the oxygen supply onboard will be exhausted by Saturday afternoon. Contact was lost with the KRI Nanggala-402, a 44 year old vessel on Wednesday during a torpedo drill with the head of the Indonesian submarine fleet aboard.<br />'' <br />''Rescue aircraft and ships have scoured the sea north of Bali with more navy ships leaving the Indonesian base of Banyuwangi early on Friday to head to the Bali Sea.<br />'' <br />''Indian Navy yesterday dispatched its Deep Submergence Rescue Vessel, DSRV to assist Indonesian Navy in search and rescue efforts.<br />'' <br />''India is among the few countries in the world capable of undertaking Search and Rescue of a disabled submarine through a DSRV. Indian Navy's DSRV system can locate a submarine upto the depth of 1000 metres utilising its state of the art Side Scan Sonar and Remotely Operated Vehicle.<br />'' <br />''<span style="color: #222222;">The German-built vessel, KRI Nanggala is one of five submarines operated by Indonesia. It was made in the late 1970s, and underwent a two-year refit in South Korea that was completed in 2012.</span><br />