Italian submarine Enrico Tazzoli (1935)

The Calvi class was an improved and enlarged version of the preceding Balilla-class submarine cruisers. They displaced 1,549 metric tons (1,525 long tons) surfaced and 2,061 metric tons (2,028 long tons) submerged. The submarines were 84.3 meters (276 ft 7 in) long, had a beam of 7.7 meters (25 ft 3 in) and a draft of 5.2 meters (17 ft 1 in).[1] They had an operational diving depth of 90 meters (300 ft).[2] Their crew numbered 77 officers and enlisted men.[1]

For surface running, the boats were powered by two 2,200-brake-horsepower (1,641 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 900-horsepower (671 kW) electric motor. They could reach 16.8 knots (31.1 km/h; 19.3 mph) on the surface and 7.4 knots (13.7 km/h; 8.5 mph) underwater. On the surface, the Calvi class had a range of 11,400 nautical miles (21,100 km; 13,100 mi) at 8 knots (15 km/h; 9.2 mph); submerged, they had a range of 120 nmi (220 km; 140 mi) at 3 knots (5.6 km/h; 3.5 mph).[2]

The boats were armed with eight 53.3-centimeter (21 in) torpedo tubes, four each in the bow and in the stern for which they carried a total of 16 torpedoes. They were also armed with a pair of 120-millimeter (4.7 in) deck guns, one each fore and aft of the conning tower, for combat on the surface. Their anti-aircraft armament consisted of two twin-gun mounts for 13.2-millimeter (0.52 in) machine guns.[1]

Enrico Tazzoli, named after Enrico Tazzoli, was laid down by Odero-Terni-Orlando at their Muggiano, La Spezia shipyard in 1932, launched on 14 October 1935 and completed the following year.[1] During the Spanish Civil War, she unsuccessfully attacked a Republican destroyer off Cartagena with four torpedoes on 27 December. During her patrol off Cartagena on 13–27 January 1937, the submarine missed a ship with two torpedoes.[3]

Italy's entry into World War II in June 1940 found Tazzoli in operations in the western Mediterranean. In October she was assigned to BETASOM, the Regia Marina's task force in the Atlantic campaign. In December Tazzoli operated off the British Isles in company with five other Italian boats, but saw little success.

Operations during the autumn and winter of 1940 showed the Italian vessels were ill-suited to conditions in the North Atlantic, so the spring 1941 saw a change in strategy by Admiral Donitz, the German U-boat Commander (BdU). The BETASOM boats were assigned to long-distance patrols into the mid and south Atlantic, in a bid to spread the commerce war further afield. During this period Tazzoli was commanded by Carlo Fecia di Cossato, one of Italy's foremost naval officers. Tazzolis next patrols, to the Azores in the spring and to West Africa in the summer were more successful, claiming three victims in each case.

In December 1941 Tazzoli was involved in the rescue of the crews from the German commerce raider Atlantis and the supply ship Python, both sunk by British cruisers in the South Atlantic. With her sister ships Calvi and Finzi she brought home over 200 survivors, a journey of several thousand miles and regarded as an epic of maritime rescue.[4]

In February 1942 Tazzoli made her most successful raiding patrol, to the Caribbean as part of Operation Neuland. Over a two-month period she sank six Allied merchant ships.[5] In summer she returned to the Caribbean, but in nearly three months found only two victims. At the end of the year Tazzoli operated off the coast of Brazil, claiming four more victims.

In March 1943 Tazzoli was handed over for conversion to a submarine transport, for blockade-running to the Far East, and her commander received a new posting.[6]

Tazzoli conducted ten war patrols over a 30-month period, and made one voyage as a blockade-runner.

Tazzoli is credited with sinking 18 ships, for a total of 96,650 GRT, making her the highest-scoring Italian submarine after Leonardo da Vinci.

Ships sunk by Enrico Tazzoli[6]

Patrol	Date	Ship	Flag	Tonnage (GRT)	Notes
3rd	12 October 1940	Orao	Yugoslavia	5,135	Freighter shelled then torpedoed while radioing; 2 killed
4th	27 December 1940	Ardanbahn	United Kingdom	4,980	No survivors from freighter of unescorted Convoy OB 263
5th	15 April 1941	Aurillac	United Kingdom	4,248	Freighter, 1 killed
5th	7 May 1941	Fernlane	Norway	4,310	Freighter with ammunition cargo, no casualties
5th	10 May 1941	Alfred Olsen	Norway	8,817	Tanker, no casualties
6th	19 August 1941	Sildra	Norway	7,313	Tanker, no casualties
8th	6 March 1942	Astrea	Netherlands	1,406	Freighter, no casualties
8th	6 March 1942	Tønsbergfjord	Norway	3,156	Freighter; 1 killed
8th	8 March 1942	Montevideo	Uruguay	5,785	Freighter; 14 killed
8th	10 March 1942	Cygnet	Greece	3,628	Freighter; no casualties
8th	13 March 1942	Daytonian	United Kingdom	6,434	Freighter; 1 killed
8th	15 March 1942	Athelqueen	United Kingdom	8,780	Tanker; 3 killed
9th	2 August 1942	Kastor	Greece	5,497	Freighter; 4 killed
9th	6 August 1942	Havsten	Norway	6,161	Tanker; 2 killed
10th	12 December 1942	Empire Hawk	United Kingdom	5,032	Freighter, no casualties
10th	12 December 1942	Ombillin	Netherlands	5,658	Freighter, no casualties
10th	21 December 1942	Queen City	United Kingdom	4,814	Freighter, 6 killed
10th	25 December 1942	Doña Aurora	United States	5,011	Freighter, 7 killed
Total:				96,165

Italian submarines of World War II

• Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
• Blair, Clay (1996). Hitler's U-Boat War, The Hunters 1939–1942. Random House. ISBN 0-394-58839-8.
• 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.
• Brice, Martin (1981). Axis Blockade Runners of World War II. Naval Institute Press. ISBN 0-87021-908-1.
• 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.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• 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.

• Enrico Tazzoli (1935) Marina Militare website