Class overview
Operators	Regia Marina
Preceded by	Argonauta class
Succeeded by	Perla class
Built	1931–1934
In commission	1933–1948
Completed	12
Lost	11
Scrapped	1
General characteristics
Type	Submarine
Displacement	691 t (680long tons) (surfaced) 850 t (837 long tons) (submerged)
Length	60.18 m (197 ft 5 in)
Beam	6.45 m (21 ft 2 in)
Draft	4.7 m (15 ft 5 in)
Installed power	1,350 bhp (1,010 kW) (diesels) 800 hp (600 kW) (electric motors)
Propulsion	2 shafts;diesel-electric 2 ×diesel engines 2 ×electric motors
Speed	14knots (26 km/h; 16 mph) (surfaced) 7.5 knots (13.9 km/h; 8.6 mph) (submerged)
Range	5,000 nmi (9,300 km; 5,800 mi) at 8 knots (15 km/h; 9.2 mph) (surfaced) 72 nmi (133 km; 83 mi) at 4 knots (7.4 km/h; 4.6 mph) (submerged)
Armament	1 × single100 mm (3.9 in)deck gun 2–4 × single13.2 mm (0.52 in)machine guns 6 × 533 mm (21 in)torpedo tubes (4 bow, 2 stern)

TheSirena-class submarines were the secondsub-class of the600 Series ofcoastal submarines built for theRegia Marina (Royal Italian Navy) during the early 1930s. Of the dozen boats built of this class, only one survivedWorld War II.

TheSirena class was an improved and enlarged version of the precedingArgonauta-classsubmarines. Theydisplaced 691metric tons (680long tons) surfaced and 850 metric tons (837 long tons) submerged. The submarines were 61.5 meters (201 ft 9 in) long, had abeam of 5.7 meters (18 ft 8 in) and adraft of 4.7 meters (15 ft 5 in). Their crew numbered 45 officers and enlisted men.^[1]

For surface running, the boats were powered by two 675-brake-horsepower (503 kW)diesel engines, each driving onepropeller shaft. When submerged each propeller was driven by a 400-horsepower (298 kW)electric motor. They could reach 14knots (26 km/h; 16 mph) on the surface and 7.5 knots (13.9 km/h; 8.6 mph) underwater.^[2] On the surface, theSirena class had a range of 5,000nautical miles (9,300 km; 5,800 mi) at 8 knots (15 km/h; 9.2 mph);^[1] submerged, they had a range of 72 nmi (133 km; 83 mi) at 4 knots (7.4 km/h; 4.6 mph).^[2]

The boats were armed with six 53.3-centimeter (21 in)torpedo tubes, four in the bow and two in the stern for which they carried a total of 12torpedoes. They were also armed with a single100 mm (3.9 in)deck gun forward of theconning tower for combat on the surface. Theanti-aircraft armament consisted of two or four13.2-millimeter (0.52 in)machine guns.^[1]

SOURCES^{[1][3][4][5][6][7][8][9][10][11][12][13][14]}

• Italian submarines of World War II

• Bagnasco, Erminio (1977).Submarines of World War Two. Annapolis, Maryland: Naval Institute Press.ISBN 0-87021-962-6.
• Brescia, Maurizio (2012).Mussolini's Navy: A Reference Guide to the Regina Marina 1930–45. Annapolis, Maryland: Naval Institute Press.ISBN 978-1-59114-544-8.
• Chesneau, Roger, ed. (1980).Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press.ISBN 0-85177-146-7.
• Frank, Willard C. Jr. (1989). "Question 12/88".Warship International.XXVI (1):95–97.ISSN 0043-0374.
• 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.

• Regia Marina The Italian Navy in World War II

• Italian 600 Series submarines
• Sirena-class submarines
• Submarines of the Regia Marina

• Articles with short description
• Short description matches Wikidata
• Ship infoboxes without an image
• Articles containing Italian-language text