With an eye toward protecting sensitive assets that lie on the ocean floor ... can easily maneuver around the sea floor. The submarine will cost roughly $5.1 billion. A standard Virginia-class ...

The newest frontier for potential combat is the ocean floor, and the U.S. and its ... that means building its most expensive spy submarine ever, a $5.1 billion high-tech vessel that would patrol ...

In August 1936, somewhere off the coast, the American military tested aerial bombardment on R-8, a Navy submarine that had ... R-8 sitting upright on the ocean floor. “The sonar data leaves ...