Italian R-class submarine

For other ship classes of the same name, see British R class submarine and United States R class submarine.

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.

Romolo-class submarine (Romolo)
Class overview
Name	Romolo
Builders	Tosi, CRDA
Operators	Regia Marina
Built	1942–1943
In service	1943
Planned	12
Completed	2
Cancelled	10
Lost	2
General characteristics
Type	Transport submarines
Displacement	2,155 t (2,121 long tons) (surfaced) 2,560 t (2,520 long tons) (submerged)
Length	86.5 m (283 ft 10 in)
Beam	7.86 m (25 ft 9 in)
Draft	5.34 m (17 ft 6 in)
Installed power	2,600 bhp (1,900 kW) (diesels) 900 hp (670 kW) (electric motors)
Propulsion	Diesel-electric 2 × diesel engines 2 × electric motors
Speed	13 knots (24 km/h; 15 mph) (surfaced) 6 knots (11 km/h; 6.9 mph) (submerged)
Range	12,000 nmi (22,000 km; 14,000 mi) at 9 knots (17 km/h; 10 mph) (surfaced) 100 nmi (190 km; 120 mi) at 3.5 knots (6.5 km/h; 4.0 mph) (submerged)
Test depth	80 m (260 ft)
Capacity	600 t (591 long tons) of cargo
Complement	63
Armament	2 × 450 mm (17.7 in) torpedo tubes (some boats) 3 × single 20 mm (0.8 in) AA guns

Design and description

The R-class submarines displaced 2,155 metric tons (2,121 long tons) surfaced and 2,560 metric tons (2,520 long tons) submerged. The submarines were 86.5 meters (283 ft 10 in) long, had a beam of 7.86 meters (25 ft 9 in) and a draft of 5.34 meters (17 ft 6 in). They had a cargo capacity of 600 tonnes (591 long tons). ^[1]

For surface running, the boats were powered by two 1,300-brake-horsepower (969 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 450-horsepower (336 kW) electric motor. They could reach 13 knots (24 km/h; 15 mph) on the surface and 6 knots (11 km/h; 6.9 mph) underwater. On the surface, the R class had a range of 12,000 nautical miles (22,000 km; 14,000 mi) at 9 knots (17 km/h; 10 mph); submerged, they had a range of 110 nmi (200 km; 130 mi) at 3.5 knots (6.5 km/h; 4.0 mph).^[2]

The boats were only armed for self-defense with three 20-millimeter (0.79 in) light anti-aircraft guns. Some boats may have been equipped with a pair of internal 45 cm (17.7 in) torpedo tubes in the bow and stern.^[1]

Boats

Twelve boats were ordered, but only two were completed, by Tosi:

• Remo, named after Remus, launched 28 March 1943 – Sunk by the British submarine HMS United 15 July 1943 in the Gulf of Taranto
• Romolo, named after Romulus, launched 21 March 1943 – Sunk by Allied aircraft near Augusta 18 July 1943.

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.

See also

• Merchant submarine
• German submarine Deutschland, an unarmed transport submarine built by Germany in World War I.

Notes

1. Chesneau, p. 307
2. Bagnasco, p. 166

Bibliography

• Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
• Chesneau, Roger, ed. (1980). Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7.
• Rohwer, Jürgen (2005). Chronology of the War at Sea 1939–1945: The Naval History of World War Two (Third Revised ed.). Annapolis, Maryland: Naval Institute Press. ISBN 1-59114-119-2.
• Frampton, Viktor (2005). "Question 9/98: Italian North African Convoys of WW II". Warship International. XLII (4): 424–425. ISSN 0043-0374.

External links

• Sommergibili Marina Militare website