Russian submarine Tver

K-456 Tver, formerly known as K-456 Vilyuchinsk (ex Kasatka), is a Russian Oscar-class submarine of the Russian Navy. It was commissioned in 1991 as part of the Russian Northern Fleet and was transferred to the Russian Pacific Fleet in September 1993. The submarine is currently based at the Rybachiy Nuclear Submarine Base, in Vilyuchinsk, near Petropavlovsk-Kamchatsky. Until 28 January 2011 it was called Vilyuchinsk, when the name was changed to Tver.^[2]

Tver in 2013
History
Russia
Name	K-456 Tver
Namesake	Tver
Commissioned	1991
Homeport	Rybachiy
General characteristics
Class & type	Oscar II-class submarine
Displacement	13,400 t, 16,400 t
Length	154 m (505 ft 3 in)
Beam	18.20 m (59 ft 9 in)
Draft	9 m (29 ft 6 in)
Propulsion	2 nuclear reactors OK-650b (HEU <= 45%[1]), 2 steam turbines, 2/7-bladed props
Speed	32 knots (59 km/h; 37 mph) submerged, 16 knots (30 km/h; 18 mph) surfaced
Test depth	300 to 1,000 m (980 to 3,280 ft) (by various estimates)
Complement	44 officers, 68 enlisted
Armament	24 × SS-N-19/P-700 Granit, 4 × 533 mm and 2 × 650 mm bow torpedo tubes

As of 2022, it is unclear if the submarine was at sea after its last exit in 2016.^[3]