The R-class or Romolo-class submarine was a group of submarines built for the Royal Italian Navy (Regia Marina Italiana) during World War II. They were designed as blockade running transport submarines for transporting high-value cargo from Europe to Japan and vice versa. Axis-occupied Europe lacked strategic materials such as tungsten, tin and some commodities such as rubber.
The R-class submarines displaced 2155t surfaced and 2560t submerged. The submarines were 86.5m (283.8feet) long, had a beam of 7.86m (25.79feet) and a draft of 5.34m (17.52feet). They had a cargo capacity of 600t.[1]
For surface running, the boats were powered by two 13000NaN0 diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 450hp electric motor. They could reach 13kn on the surface and underwater. On the surface, the R class had a range of 12000nmi at ; submerged, they had a range of 110nmi at .[2]
The boats were only armed for self-defense with three 20sp=usNaNsp=us light anti-aircraft guns. Some boats may have been equipped with a pair of internal 45cm (18inches) torpedo tubes in the bow and stern.[1]
Twelve boats were ordered, but only two were completed, by Tosi:
The remaining 10 hulls were scuttled incomplete and scrapped after the war.
The sail of submarine R12 is now exhibited as a monument on the seafront of Gaeta.
. Chronology of the War at Sea 1939–1945: The Naval History of World War Two. Naval Institute Press. Annapolis, Maryland. 2005. Third Revised. 1-59114-119-2. Jürgen Rohwer.