171125-N-TW634-032 ATLANTIC OCEAN (Nov. 25, 2017) Sailors assigned to Undersea Rescue Command (URC) discuss submarine rescue procedures aboard the Norwegian construction support vessel Skandi Patagonia. Undersea Rescue Command, the U.S. Navy's only submarine rescue unit, is mobilized to support the Argentine government's search and rescue efforts for the Argentine Navy diesel-electric submarine A.R.A San Juan (S 42). (U.S. Navy photo by Mass Communication Specialist 2nd Class Derek Harkins/Released)