Photo de stock - Feb. 29, 2012 - What A Difference 25 Years Makes: Submarine style changes are exemplified in these historical undersea ships which were launched a quarter century apart at the Groton, Conn. shipyard of General Dynamics Corporation's Electric Boat Division, the nation's leading sub builder. At left is the US Cuttlefish, first sub built in Groton, shown going down the ways on November 21, 1993. The clipper-ship type bow of the Cuttlefish was conventional right through World War II and was necessary because diesel power made them only part-time submersibles. The streamlined atomic sub Skip jack is shown (right) at her launching this year. Nuclear power made the underwater ship a true submersible and led to adoption of many aerodynamic principles for submarines. (Credit Image: © Keystone Pictures USA/ZUMAPRESS.com)