Sea Trials Of Skipjack. First sea trials of the nuclear submarine Skipjack. With its radical fish-type hull, and the mighty power of atomic engines, the Skipjack boasts sensational underwater speed and maneuverability, making it an even more revolutionary craft than the Nautilus. Sub plows through water, partly surfaced. Interiors of submarine crew at work with equipment, periscope. Sub goes almost completely under, surfaces.