Transcript for Search continues for missing Argentine submarine with 44 crew members onboard

reshef. Now, to what could be new science of hope for a missing submarine. It disappeared on Wednesday with 44 people on board. Emergency signals have reportedly been ke ticketed now. The U.S. Navy sends in its most sophisticated rescue systems. Reporter: Dan and Paul larks good morning. It has been four days since the naval submarine Ara San Juan first went missing. It looks as though the crew may be trying to reach out for help. This morning, there are new science of hope as authorities desperately search for 44 crew members on board a missing Argentinian submarine. Seen here, before it vanished. Emergency signals believed to have come from the submarine have been detected. Or general tine officials say seven failed satellite calls were picked up. This, as one of the U.S. Navy's most sophisticated underwater rescue systems travels to Argentina to help look for the sub. The problem here, although the Navy is sending its best rescue gear, if you don't know where the submarine is, you can't effect that rescue. Reporter: One system can save up to six people at a time. And reach depths of 850 feet. No one appears to know exactly where the submarine is. It's been missing since Wednesday. The Argentine Navy says it lost contact with the decades old sub while it was on a routine trip in a base of ushuaia to the host base. One theory is that a fire may have knocked out power, cutting off their communication system. This is not the first submarine the to go missing. August 2000, the Russian nuclear club marine kirsk failed. In 1968, the uss scorpion sank beneath the atlantic ocean with 99 crewmen. Why it went down is still unknown. With the U.S. Navy's go undersea rescue sons the way to Argentina to look for the submarine, everyone is hoping for a different and positive outcome. Stephanie, thank you. Let's bring in retired marine

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