John Francis Ropek this nuclear submarine, Ropek was involved in pioneering oceanographic studies under the polar ice cap of the North Pole, resulting in the report "Characteristics of Polar Ice Observed During the 1957 Arctic Cruise of the USS Nautilus" (Defense Technical Information Center 1958). As a scientist he published many technical papers, such as "US Navy Hydrographic Office synoptic and prognostic wave charts" (US Navy Hydrographic Office 1955), and "An Application of Naval Oceanographic Development to Inland Waters" (Defense Technical Information Center 1967). Later, Ropek was deputy director of the prediction division of the Naval Oceanographic Office. Late in life he lived
Sail (submarine) as an observation platform. It also provides an entrance and exit point on the submarine that has enough freeboard to prevent the submarine being swamped. Underwater the sail acts as a vertical stabilizer. In some submarines, the sail also supports diving planes, which are control surfaces used for underwater stability and steering. Sail (submarine) In naval parlance, the sail (American usage) or fin (European/Commonwealth usage) of a submarine is the tower-like structure found on the dorsal (topside) surface of submarines. Submarine sails once housed the conning tower (command and communications data center), the periscope(s), radar and communications masts (antenna), though