The Pisani-class submarines were built for the Italian: [[Regia Marina]] (Royal Italian Navy) during the late 1920s. They played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
Designed in parallel with the s, the Pisani class was larger to accommodate more fuel and give them more range. They displaced 866LT surfaced and 1040LT submerged. The submarines were 68.2m (223.8feet) long, had a beam of 6.090NaN0 and a draft of 4.93m (16.17feet). They had an operational diving depth of 90m (300feet). Their crew numbered 48 officers and enlisted men.[1]
For surface running, the boats were powered by two 15000NaN0 diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 550hp electric motor. Like the Mamelis, their stability was poor and they had to be modified with bulges after completion. This reduced their speeds from 17.25kn on the surface and underwater to and respectively. On the surface, the Pisani class had a range of 5000nmi at ;[1] submerged, they had a range of 70nmi at .[2]
The boats were armed with six 53.3cm (21inches) torpedo tubes, four in the bow and two in the stern for which they carried a total of nine torpedoes. They were also armed with a single 102mm deck gun forward of the conning tower for combat on the surface. Their anti-aircraft armament consisted of two 13.2adj=onNaNadj=on machine guns.[1]
| Ship | Builder | Laid down[3] | Launched | Completed | Fate |
|---|---|---|---|---|---|
| Cantiere Navale Triestino, Trieste | 27 January 1926 | 24 March 1927 | 15 September 1929 | Decommissioned 16 April 1942, converted into an oil barge | |
| 3 December 1925 | 26 December 1927 | 10 July 1929 | Scrapped, 1943 | ||
| 1 February 1926 | 14 November 1928 | 31 October 1929 | Decommissioned 16 April 1942, converted into a battery-charging hulk | ||
| 18 November 1925 | 24 November 1927 | 16 June 1929 | Decommissioned, 23 March 1947 |
During the Spanish Civil War, Vettore Pisani made at least one patrol off the Catalan coast in August 1937 during which she made one unsuccessful attack.[4]