The defence ministry is now trying to trace the location of the seven failed satellite calls received on Saturday.
Is something lost in the translation perhaps? You can't do a satellite call unless you put an antenna above the surface of the ocean right?
Is some sort of tethered emergency buoy deployed?
Some information on the U.S. Navy rescue systems deployed:
URC is deploying two independent rescue assets based on a number of factors, including the varying depth of ocean waters near South America’s southeastern coast and the differing safe operating depths of the two rescue systems.
Three U.S. Air Force C-17 Globemaster III and one U.S. Air Force C-5 Galaxy aircraft will transport the first rescue system, the Submarine Rescue Chamber (SRC) and underwater intervention Remotely Operated Vehicle (ROV) from Miramar to Comodoro Rivadavia, Argentina. The four aircraft are scheduled to depart Miramar Nov. 18 and arrive in Argentina Nov. 19.
The second rescue system, the Pressurized Rescue Module (PRM) and supporting equipment will be transported via additional flights and is scheduled to arrive in Argentina early next week.
https://news.usni.org/2017/11/18/u-s...sing-submarine