Russian submarine K - 84 Ekaterinburg K - 84 " Ekaterinburg " ( ) is a Project 667BDRM " Delfin " class ( NATO reporting name : Delta IV ) nuclear - powered ballistic missile submarine . The submarine was laid down on 17 February 1982 at the Russian Northern Machine - Building Enterprise ( Sevmash ) . She was commissioned into the Soviet Navy on 30 December 1985 . After the collapse of the Soviet Union , the submarine continued to serve in the Russian Navy . Initially known only by her hull number , in February 1999 she was renamed after the city of Yekaterinburg . Construction . Construction of the nuclear submarine " Ekaterinburg " ( K - 84 ) began at the Northern Machinebuilding Enterprise ( Sevmash ) in Severodvinsk on 17 February 1982 , before being commissioned into the Soviet Navy on 30 December 1985 . She was the second of the seven - boat Project 667BDRM " Delfin " class , which was developed at the Rubin Design Bureau in September 1975 . A ballistic missile submarine , she was designed primarily to carry up to 16 R - 29RM " Shtil " ( NATO designation : SS - N - 23 Skiff ) SLBM for use against military and industrial facilities in the case of a nuclear war . Each " Shtil " missile carries ten 100 kt multiple independently targeted reentry vehicle s , and has a circular error probable of . She is also equipped with RPK - 7 " Veter " ( NATO designation : SS - N - 16 Stallion ) anti - ship missiles for use against large surface vessels , and self - defense torpedoes . Operational history . After commissioning , " Ekaterinburg " was deployed to the base at Olenya Bay , and during the second half of 1986 underwent acoustic trials . In August 1989 , " Ekaterinburg " conducted a failed launch of all its missile under Operation Behemoth . Four months later , in December 1989 , she was the first submarine to attempt to launch all her missiles while underwater ; the first launch was successful , though the second was not . In 1993 , she was transferred to the base at Sayda - Guba . On 3 December 1996 , " Ekaterinburg " entered the Zvezdochka shipyard in Severodvinsk for an overhaul , though work did not begin until March 1998 . She re - entered service in 2003 , based in Yagelnaya Bay . She test - fired R - 29RMU Sineva missiles in December 2003 and June 2004 , and during Northern Fleet exercises in August 2005 fired missiles at the Kamchatka range . Also in 2005 , " Ekaterinburg " was awarded the Navy Commander ' s Prize for her missile launches . In 2006 , she successfully fired missiles at the Chizha Range from the North Pole . On 20 May 2011 , the boat fired the first R - 29RMU2 Liner SLBM , aimed at the Kura Test Range . Fire incident and near nuclear catastrophe . On 29 December 2011 around 1220 UTC , " Ekaterinburg " caught fire while in drydock in Murmansk , and after several hours of firefighting efforts , she was partially sunk in an effort to control the fire . Initial statements from Russian authorities indicate there were no injuries or radiation leakage , and that the vessel was not carrying any weapons as she was drydocked for repairs . The fire apparently began when sparks from welding being done on the boat ' s hull ignited wooden scaffolding around the ship , then spread to the flammable rubber coating covering the hull . Russian President Dmitry Medvedev ordered the repair of the submarine and a thorough investigation of the incident on 30 December 2011 . The boat ' s hydro acoustic system was disabled in the fire . Some sources speculate that the submarines pressure hull suffered possible structural damage due to the intense heat , the temperature inside the torpedo room allegedly rose to 60 - 70 °C . A commission will study the damage to the submarine and determine whether it is economical to repair it . A Zvezdochka shipyard spokesperson said that the repairs will take more than a year . On January 12 , 2012 ITAR - TASS reported that the repair of the submarine will take three to four years . The repair will be combined with a scheduled refit that was to start in 2013 . As it will be some months before the submarine can be transferred to the shipyard due to winter sea ice , the repairs will begin in May – June , 2012 , so the submarine is not expected to return to service before 2015 . On February 14 , 2012 , " Vlast " reported that the submarine had been carrying 16 R - 29RM Shtil ( NATO designation SS - N - 23 Skiff ) SLBMs , armed with four nuclear warheads in each missile , at the time of the fire , though officials had said at the time of the fire that no nuclear weapons were on board , as they had been unloaded before the fire broke out . According to " Vlast " , the presence of nuclear weapons on the burning vessel would have meant that " Russia , for a day , was on the brink of the biggest catastrophe since the time of Chernobyl . " Viktor Litovkin , editor - in - chief of Nezavisimoye Voyennoye Obozreniye , seriously doubted that a nuclear submarine could undergo maintenance with missiles and torpedoes on board because an off - duty submarine cannot have any weapons on board due to the Russian - American Prague agreement on nuclear arms . Litovkin explains that “ when such a submarine is in dock , all missile pits are opened so that the Americans could check from surveillance satellites that there are no missiles in them . . . Moscow and Washington notify each other when nuclear missile carriers are going off duty for maintenance and Russia does the same surveillance of American subs . " During 1985 to 1989 , US submarines did not have to remove their ballastic missiles ( with nuclear warheads ) to enter what was known as a floating drydock . This would seem agree with the possibility of the Russian sub having its nuclear weapons on board at the time . The reference to some US / Russian agreement may not have covered floating drydocks or Subs lifted out of the water on these for short duration repairs .