Italian submarine Velella (1936)

History
Kingdom of Italy
Name	Velella
Builder	Cantieri Riuniti dell'Adriatico, Monfalcone
Launched	12 December 1936
Fate	Sunk by HMS Shakespeare, 7 September 1943
General characteristics
Class and type	Argo-class submarine
Displacement	793 t (780 long tons) (surfaced); 1,016 t (1,000 long tons) (submerged);
Length	63.15 m (207 ft 2 in)
Beam	6.93 m (22 ft 9 in)
Draft	4.46 m (14 ft 8 in)
Installed power	1,500 kW) (diesels); 800 hp (600 kW) (electric motors);
Propulsion	2 shafts; diesel-electric; 2 × diesel engines; 2 × electric motors;
Speed	14 knots (26 km/h; 16 mph) (surfaced); 8 knots (15 km/h; 9.2 mph) (submerged);
Range	10,176 nmi (18,846 km; 11,710 mi) at 8.5 knots (15.7 km/h; 9.8 mph) (surfaced); 100 nmi (190 km; 120 mi) at 3 knots (5.6 km/h; 3.5 mph) (submerged);
Test depth	90 m (300 ft)
Armament	1 × single 100 mm (3.9 in) deck gun; 4 × single 13.2 mm (0.52 in) machine guns; 6 × 533 mm (21 in) torpedo tubes (4 bow, 2 stern);

Velella was one of a pair of submarines ordered by the Portuguese government, but taken over and completed for the Regia Marina (Royal Italian Navy) during the 1930s.

Design and description

The Argo-class submarines displaced 793 metric tons (780 long tons) surfaced and 1,016 metric tons (1,000 long tons) submerged. The submarines were 63.15 meters (207 ft 2 in) long, had a beam of 6.93 meters (22 ft 9 in) and a draft of 4.46 meters (14 ft 8 in).^[1] They had an operational diving depth of 90 meters (300 ft).^[2] Their crew numbered 46 officers and enlisted men.^[1]

For surface running, the boats were powered by two 750-

propeller shaft. When submerged each propeller was driven by a 400-horsepower (298 kW) electric motor. They could reach 14 knots (26 km/h; 16 mph) on the surface and 8 knots (15 km/h; 9.2 mph) underwater. On the surface, the Argo class had a range of 10,176 nautical miles (18,846 km; 11,710 mi) at 8 knots (15 km/h; 9.2 mph); submerged, they had a range of 100 nmi (190 km; 120 mi) at 3 knots (5.6 km/h; 3.5 mph).^[2]

The boats were armed with six internal 53.3-centimeter (21 in)

13.2-millimeter (0.52 in) machine guns.^[1]