Italian submarine Velella (1936)

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 780 LT surfaced and 1000 LT submerged. The submarines were 63.15 m long, had a beam of 6.93 m and a draft of 4.46 m. They had an operational diving depth of 90 m. Their crew numbered 46 officers and enlisted men.

For surface running, the boats were powered by two 750 bhp diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 400 hp electric motor. They could reach 14 kn on the surface and 8 kn underwater. On the surface, the Argo class had a range of 10176 nmi at 8 kn; submerged, they had a range of 100 nmi at 3 kn.

The boats were armed with six internal 53.3 cm torpedo tubes, four in the bow and two in the stern for which they carried a total of 10 torpedoes. They were also armed with a single 100 mm deck gun, forward of the conning tower, for combat on the surface. The light anti-aircraft armament consisted of four single 13.2 mm machine guns.

Service
Velella was built by Cantieri Riuniti dell'Adriatico in its Monfalcone shipyard. The submarine had initially been ordered in 1931, but was acquired by the Italians when Portugal cancelled the order. She was launched in 1936, and saw action in the Second World War.