Osetr-class submarine

	Russian submarine Sig
Class overview
Name	Osetr class
Builders	Libau Arsenal, Latvia
Operators	Imperial Russian Navy
In commission	1905–1913
Completed	6
Retired	6
General characteristics
Type	Submarine
Displacement	153 tons surfaced; 187 tons submerged;
Length	22 m (72 ft 2 in)
Beam	3.6 m (11 ft 10 in)
Draught	3.7 m (12 ft 2 in)
Propulsion	2 shafts: petrol / electric; 2 × 120 hp (89 kW) / 2 x 65 hp (48 kW);
Speed	8.5 knots (15.7 km/h; 9.8 mph) surfaced ; 4.5 knots (8.3 km/h; 5.2 mph) submerged;
Complement	12 (including 2 officers)
Armament	3 × 18-inch torpedo tubes (2 bow, 1 stern)

The Osetr class were a group of submarines built for the Imperial Russian Navy during the Russo–Japanese War. The boats were ordered in the 1904 emergency programme. The boats were designed by American engineer Simon Lake and had wheels fitted for moving around on the sea bed as well as wet/dry chambers for divers. Osetr was the former Protector sold by Lake to the Russians and re-assembled in Russia. The diving depth was around 30 metres (98 ft).

Ships

All ships were built by the Lake company at the Libau Arsenal (Latvia) and were launched in 1904

Ship	Namesake	Service / Fate
Bychok - Бычок	Goby	Decommissioned 1913
Kefal - Кефаль	Mullet	Decommissioned 1913
Osetr - Осётр (ex Protector)	Sturgeon	Decommissioned 1913
Paltus - Палтус	Halibut	Decommissioned 1913
Plotva - Плотва	Roach	Decommissioned 1913
Sig - Сиг	Coregonus	Decommissioned 1913

References

Conway's All the World's Fighting Ships 1906–1921