Kaiman-class submarine

Class overview
Name:	Kaiman class
Builders:	W:m Crichton & C:o Okhta shipyard, Saint Petersburg
Operators:	Imperial Russian Navy
Built:	1906–1911
In commission:	1911–1918
Planned:	4
Completed:	4
Lost:	4
General characteristics
Displacement:	409 long tons (416 t) surfaced 482 long tons (490 t) submerged
Length:	134 ft 6 in (41.0 m)
Beam:	12 ft 2 in (3.7 m)
Draft:	16 ft 1 in (4.9 m)
Installed power:	2 × gasoline engines (400 bhp (300 kW)) 2 × electric motors (200 hp (150 kW))
Propulsion:	2 × propeller shafts
Speed:	8.4 knots (15.6 km/h; 9.7 mph) (surfaced) 7.5 knots (13.9 km/h; 8.6 mph) (submerged)
Range:	750 nmi (1,390 km; 860 mi) at 8 knots (15 km/h; 9.2 mph) (surfaced) 24 nmi (44 km; 28 mi) at 7 knots (13 km/h; 8.1 mph) (submerged)
Test depth:	90 feet (27 m)
Complement:	34
Armament:	2 × bow and 2 × stern 18-inch (457 mm) torpedo tubes 2 × external Dzhevetsky drop-collars 1 × 47-millimeter (1.9 in) gun

The Kaiman class were a class of submarines built for the Imperial Russian Navy before World War I. They were designed by Simon Lake and built at the W:m Crichton & C:o Okhta shipyard in Saint Petersburg. The boats had numerous defects resulting in a legal battle between Lake and the Russian Government. The boats were impounded in 1910 and rebuilding work took place to remedy some of the defects. The boats finally commissioned in 1911 and served in the Baltic Fleet.

Ships

All four ships were built by Crichton Yard, Saint Petersburg, served in the Baltic Fleet and were scuttled in Reval in February 1918 to prevent capture by the Germans.

Ship	Laid Down	Launched	Completed	Fate
Kaiman - Кайман	1906	November 1907	1911	Scuttled 25 February 1918 at Reval
Alligator - Аллигатор		1908
Krokodil - Крокодил
Drakon - Дракон		27 June 1908