Calvi-class submarine

Giuseppe Finzi
Class overview
Builders	Odero-Terni-Orlando, Muggiano, La Spezia
Operators	Regia Marina
Preceded by	Pietro Micca
Succeeded by	Foca class
Built	1935
In commission	1936–1943
Completed	3
Lost	2
Scrapped	1
General characteristics
Type	Submarine cruiser
Displacement	1,549 t (1,525 long tons) (surfaced) 2,061 t (2,028 long tons) (submerged)
Length	84.3 m (276 ft 7 in)
Beam	7.7 m (25 ft 3 in)
Draft	5.2 m (17 ft 1 in)
Installed power	4,400 bhp (3,300 kW) (diesels) 1,800 hp (1,300 kW) (electric motors)
Propulsion	2 shafts; diesel-electric 2 × diesel engines 2 × electric motors
Speed	16.8 knots (31.1 km/h; 19.3 mph) (surfaced) 7.4 knots (13.7 km/h; 8.5 mph) (submerged)
Range	11,400 nmi (21,100 km; 13,100 mi) at 8 knots (15 km/h; 9.2 mph) (surfaced) 120 nmi (220 km; 140 mi) at 3 knots (5.6 km/h; 3.5 mph) (submerged)
Test depth	90 m (300 ft)
Crew	77
Armament	8 × 533 mm (21 in) torpedo tubes (4 bow, 4 stern) 2 × single 120 mm (4.7 in) deck guns 2 × twin 13.2 mm (0.52 in) machine guns

The Calvi class was a class of three submarines built by Oderno-Terni-Orlando in Genoa for the Royal Italian Navy (Italian: Regia Marina). The submarines were built in 1935, and all three served in the Mediterranean at the start of the Second World War. The boats were transferred to the BETASOM Atlantic submarine base at Bordeaux in August 1940. In December 1941 the boats were used for a rescue mission of 254 sailors from the sunken German auxiliary cruiser Atlantis. After Calvi had been sunk, Finzi and Tazzoli were selected for conversion to "transport submarines" in order to exchange rare or irreplaceable trade goods with Japan. Cargo capacity of 160 tons reduced reserve buoyancy from 20–25% to 3.5–6%; and armament was reduced to defensive machine guns.^[1]