Adua-class submarine

RSMG Adua
Class overview
Name	Adua class
Builders	OTO, Muggiano CRDA, Monfalcone Tosi, Taranto
Operators	Regia Marina, Brazilian Navy
Preceded by	Perla class
Succeeded by	Acciaio class
In commission	1937–1947
Completed	17
Lost	16
General characteristics
Type	Submarine
Displacement	680 long tons (691 t) surfaced 844 long tons (858 t) 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	1,200 bhp (890 kW) (diesels) 800 hp (600 kW) (electric motors)
Propulsion	Diesel-electric 2 × diesel engines 2 × electric motors
Speed	14 knots (26 km/h; 16 mph) surfaced 7.5 knots (13.9 km/h; 8.6 mph) submerged
Range	3,180 nmi (5,890 km; 3,660 mi) at 10.5 knots (19.4 km/h; 12.1 mph) surfaced 74 nmi (137 km; 85 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth	80 m (260 ft)
Complement	45
Armament	6 × 533 mm (21 in) torpedo tubes (4 bow, 2 stern) 1 × single 100 mm (4 in) / 47 caliber deck gun 1 or 2 x single 13.2 mm (0.52 in) anti-aircraft guns

The Adua-class submarine was the fourth sub-class of the 600 Series of coastal submarines built for the Regia Marina (Royal Italian Navy) during the 1930s. There were 17 submarines in this class, almost all named after places in Ethiopia which had been an Occupied by Italy since 1936, but only one, Alagi, survived World War II. Three submarines of this class (Gondar, Ascianghi, and Neghelli) were sold to Brazil before the war and replaced with submarines of the same names.