SE73512 USN SUBMARINE GUPPY 1B CLASS (ITALIAN NAVY SS LEONARDO DA VINCI)

GUPPY (Greater Underwater Propulsion Power Program) is the name of the modernization program undertaken by the US Navy after 1945, aimed at significantly improving the combat capabilities of Gato, Balao and Tench class submarines. The main emphasis was placed on improving underwater speed, durability and maneuverability in the water. The work was enormously based on the conclusions and design solutions obtained from the captured German U-boats type XXI. The program was implemented in several stages, one of which was GUPPY II. Ship conversions under this part of the program took place in 1947-1951. As a result, artillery weapons were removed from the decks, the kiosk and the hull were redesigned, significantly improving their hydrodynamic properties, and SV radars were also mounted on some ships under the GUPPY II. The driveline was also modernized, using low-speed engines instead of high-speed engines. These changes significantly increased the maximum underwater speed of the ships (from about 9 to 16 knots) and the swimming range. 24 submarines were modernized to this standard.