| History | |
|---|---|
 Kingdom of Italy | |
| Name | Ametista |
| Namesake | Amethyst |
| Builder | Odero-Terni-Orlando,Muggiano |
| Laid down | 16 September 1931 |
| Launched | 24 April 1933 |
| Completed | 1 April 1934 |
| Fate | Scuttled 12 September 1943 |
| General characteristics | |
| Class & type | Sirena-classsubmarine |
| Displacement | |
| 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 | |
| Propulsion |
|
| Speed |
|
| Range |
|
| Crew | 45 |
| Armament |
|
Ametista was thelead ship ofher class of a dozensubmarines, the secondsub-class of the600 Series ofcoastal submarines built for theRegia Marina (Royal Italian Navy) during the early 1930s.
TheSirena class was an improved and enlarged version of the precedingArgonauta-classsubmarines. Theydisplaced 691metric tons (680long tons) surfaced and 850 metric tons (837 long tons) submerged. The submarines were 61.5 meters (201 ft 9 in) long, had abeam of 5.7 meters (18 ft 8 in) and adraft of 4.7 meters (15 ft 5 in). Their crew numbered 45 officers and enlisted men.[1]
For surface running, the boats were powered by two 675-brake-horsepower (503 kW)diesel engines, each driving onepropeller shaft. When submerged each propeller was driven by a 400-horsepower (298 kW)electric motor. They could reach 14knots (26 km/h; 16 mph) on the surface and 7.5 knots (13.9 km/h; 8.6 mph) underwater.[2] On the surface, theSirena class had a range of 5,000nautical miles (9,300 km; 5,800 mi) at 8 knots (15 km/h; 9.2 mph);[1] submerged, they had a range of 72 nmi (133 km; 83 mi) at 4 knots (7.4 km/h; 4.6 mph).[2]
The boats were armed with six 53.3-centimeter (21 in)torpedo tubes, four in the bow and two in the stern for which they carried a total of 12torpedoes. They were also armed with a single100 mm (3.9 in)deck gun forward of theconning tower for combat on the surface. Theiranti-aircraft armament consisted of two or four13.2-millimeter (0.52 in)machine guns.[1]
Ametista waslaid down byOdero-Terni-Orlando (OTO) at theirMuggiano,La Spezia shipyard in 1931,launched on 24 April 1933 and completed the following year.[1]
