The larger Oscar II submarines were built at the Sevmash yard in Severodvinsk. Credit: Sergey Konovalov / Shutterstock.
Oscar II Kursk submarine sank in the Barents Sea in August 2000. Credit: Andrei Luzik.
The submarines are equipped with SS-N-19 Granit cruise missiles.

SSGN Oscar II class cruise-missile submarines (Project 949A/Antey class) are designed primarily to attack NATO aircraft carrier battle groups. To cope with its resource problems, the Russian Navy, in the early 1990s, made an effort at preserving its core submarine force capabilities.

The Russian Navy continued to invest in new construction. In the late 1990s, it completed several new submarines of the third generation Oscar II. 11 of the larger Oscar II submarines were built between 1985 and 1999 at the Sevmash yard in Severodvinsk. Three have been decommissioned and one, the Kursk, sank. Two Oscar II submarines are active with the Northern Fleet and five with the Pacific Fleet.

The Pacific Fleet is set to upgrade four Oscar II submarines with 3M-54 Kalibr family of cruise missiles by 2021 as part of a multi-year programme. The submarines can also be fitted with other cruise missiles, including 3M-54 anti-ship, 3M-14 land-attack missiles, and PT91 anti-submarine warfare (ASW) torpedoes.

The upgraded submarines will be designated Project 949AM.

Oscar II submarine design and features

Oscar II submarines have a length of 155m, depth of 600m and a displacement of 24,000t. Each submarine has the capacity to accommodate a total of 107 crew members.

Designed to deliver missile blows on groups of ships and coastal installations, the submarine constitutes an updated version of Project 949 with one additional compartment to improve the inner arrangement of the armament and equipment.

The Oscar II is a double-hulled design and is divided into ten major compartments. The reinforced rounded cover of the sail is intended to break through the ice of the Artic ice cap. The two periscopes, radio-sextant and radar masts are located within the retractable devices area.

The HF and UHF radio-masts, radio direction-finder masts and satellite communication and navigation masts are located on the airshaft to feed compressors. The submarine is fitted with a floating antenna buoy to receive radio messages, target designation data and satellite navigation signals at a great depth and under the ice.

The bow horizontal hydroplanes are retracted into the hull. The main mechanisms have modular design and two-cascade shock-absorbing system.

As with other Russian submarines, the Oscar features a double hull, comprising an inner pressure hull and an outer hydrodynamic hull. The 3.5m separation between the inner and outer hulls on the Oscar provides significant reserve buoyancy and improved survivability against conventional torpedoes. These large submarines are said to be slow to dive and manoeuvre, though they are credited with a submerged speed of about 30 knots, sufficient to keep pace with their targets.

The improved Oscar II is about 10m longer than the Oscar I, possibly making room for a quieter propulsion system, and features upgraded electronic systems. The Oscar II is also characterised by a substantially enlarged fin, which should improve underwater manoeuvrability.

Oscar II weapons systems

The submarine is equipped with 24 SS-N-19 Granit (NATO codename “Shipwreck”) cruise missiles with a range of 550km. The missile has a length of 10.5m and weighs 6.9t with a warhead weighing 1000kg. Its speed is Mach 1.5.

“As with other Russian submarines, the Oscar features a double hull, comprising an inner pressure hull and an outer hydrodynamic hull.”

Under the START treaty, nuclear warheads for these missiles have been replaced with high-explosive warheads. The missiles, which are launched while the submarine is submerged, are fired from tubes fixed at an angle of approximately 40°.

The tubes, arranged in two rows of twelve, are each covered by six hatches on each side of the sail, with each hatch covering a pair of tubes. The launchers are placed between the inner pressure hull and the outer hydrodynamic hull.

The torpedo tubes fire both torpedoes and shorter-range anti-ship missiles, and a combination of some two dozen weapons are carried, including the SS-N-16 missile. The SS-N-16 has a range of 50km and is powered by a liquid fuel turbojet engine. It can carry either an explosive warhead or a Type 40 torpedo.

In the 1980s, the Rubin Design Bureau was responsible for developing a number of third-generation nuclear-powered submarines with cruise missiles, including Projects 949 (“Granit”, “Oscar I”) and 949A (“Antey”, “Oscar II”). The Bureau took the lead in using naval cruise missiles, designing the first cruise missile nuclear submarine – Project 659 (“Echo I”), then Project 675 (“Echo II”) and related modifications.

The Kursk disaster

In August 2000, the Oscar II nuclear-powered cruise missile submarine, Kursk (K 141), sank in the Barents Sea, with the loss of all 118 crew. Commissioned in 1994, the Kursk was part of the Russian Northern Fleet. From Norwegian seismological records, it appeared that the submarine was destroyed by two explosions.