Acciaio-class submarine
The Acciaio-class submarine was the fifth subclass of the 600 Series of coastal submarines built by the Regia Marina. They were completed during the early 1940s and saw service in World War II.
Design and description
The Acciaios were a development of the and designs, with some improvements, such as a lower conning tower to improve stability and reduce the silhouette. Of the 13 vessels in the class, six were built by CRDA at Monfalcone, four by OTO at Muggiano, and three by Cantieri navali [Tosi di Taranto|Cantieri Tosi] in Taranto, the three main Italian shipyards for submarines. They were single-hulled with side tanks, and built to a Bernardis design, though the Tosi vessels had more powerful engines, giving a surface speed of.The word Acciaio means "steel", and all vessels in this class were named for metals and minerals.