Izyaslav-class destroyer

The Izyaslav class (Russian: Изяслав) were a class of destroyer flotilla leaders built for the Baltic Fleet of the Imperial Russian Navy during World War I.

Karl Marx, the former Izyaslav
Class overview
Name	Izyaslav class
Builders	Bocker and Lange, Reval, Estonia
Operators	Imperial Russian Navy  Soviet Navy  Estonian Navy  Peruvian Navy
Preceded by	Orfey class
In commission	1916–1954
Planned	5
Completed	3
Cancelled	2
Lost	2
Scrapped	1
General characteristics (as built)
Type	Destroyer
Displacement	1,390 long tons (1,410 t)
Length	107 m (351 ft 1 in)
Beam	9.5 m (31 ft 2 in)
Draught	4.1 m (13 ft 5 in)
Installed power	5 Normand boilers 32,700 shp (24,400 kW)
Propulsion	2 shafts; 2 steam turbines
Speed	31 knots (57 km/h; 36 mph)
Range	1,880 nmi (3,480 km; 2,160 mi) at 21 knots (39 km/h; 24 mph) (estimated)
Complement	150
Armament	4–5 × single 4 in (102 mm) guns 3 × triple 17.7 in (450 mm) torpedo tubes 1 × 2.5 in (64 mm) AA gun 1 × 3 in (76 mm) Lender AA gun 80 mines

Design and description

The Izyaslav-class ships were designed to serve as flotilla leaders for the Novik-type destroyers.^[1] The ships normally displaced 1,390 long tons (1,410 t)^[2] and 1,570–1,590 long tons (1,600–1,620 t) at full load. They measured 107 meters (351 ft 1 in) long overall with a beam of 9.5 meters (31 ft 2 in), and a draft of 4.1 meters (13 ft 5 in). The Izyslavs were propelled by two steam turbines, each driving one propeller using steam from five Normand-Vulcan boilers. The turbines were designed to produce a total of 32,700 shaft horsepower (24,400 kW) for an intended maximum speed of 35 knots (65 km/h; 40 mph).^[3] During the ships' sea trials, they only reached 31.7–31.8 knots (58.7–58.9 km/h; 36.5–36.6 mph) despite outputs of 34,975–35,700 shp (26,081–26,621 kW). The ships carried enough fuel oil to give them an estimated range of 1,880 nautical miles (3,480 km; 2,160 mi) at 21 knots (39 km/h; 24 mph). Their crew numbered 150.^[2]

The Izyaslav-class ships were originally intended to have an armament of two single four-inch (102 mm) Pattern 1911 Obukhov guns, one each at the bow and stern, and a dozen 450-millimeter (17.7 in) torpedo tubes in six double mounts. The Naval General Staff changed this to four triple mounts once they became available and then decided to remove a torpedo mount in exchange for another four-inch gun at the stern on 20 August 1915 while the ships were still under construction. Another gun was ordered to be added on the forecastle on 25 May 1916. Izyaslav was complete with this gun armament, but her sister ships had another gun added on the stern in April 1917.^[4] All of these guns were on the centerline and interfered with each other's movements.^[5] Anti-aircraft defense was provided by a 2.5-inch (64 mm) Pattern 1916 anti-aircraft (AA) gun and a 3-inch (76 mm) Lender AA gun, both in single mounts amidships. The Izyaslavs were completed with one triple torpedo mount between the forward funnels and two mounts aft of the rear funnel. They could carry 80 M1912 naval mines. They were also fitted with a Barr and Stroud rangefinder and two 60-centimeter (24 in) searchlights.^[3]

Ships

These ships were built by Bocker and Lange in Reval, Estonia. The ships were delayed due to ordering machinery from Switzerland which was embargoed on the outbreak of World War I. New machinery was ordered from Britain.^[2]

Construction data

Ship	Launched	Fate
Avtroil - renamed Lennuk - renamed Almirante Guise	13 January 1915	Captured by the British in 1918, given to the Estonian Navy and sold by the Estonians to Peru, in 1933, scrapped, 1954
Izyaslav - renamed Karl Marx	27 June 1915	Sunk, 8 August 1941
Prymyslav - renamed Kalinin	9 August 1915	Sunk, 28 August 1941
Bryachislav	1 October 1915	Evacuated to Petrograd but scrapped incomplete, 1923
Fedor Stratilat	1915	Evacuated to Petrograd but scrapped incomplete, 1923

Avtroil, c. 1913–1919

Kalinin c. 1925-1941