Citation :

The B-90 “Sarov”, which is part of the project 20 120, left the shipyard on Friday, a press note from the Sevmash company reports. The vessel is unique with its combination of diesel and reactor engine. The sub is likely to be applied by the Northern Fleet as spy vessel in northern waters. According to Rosbaltnord.ru the vessel is the first of its kind in Russia and construction has been conducted in strict secrecy. The crew, 52 officers and midshipmen, have already been trained at the educational centre of Russia’s Navy. The submarine, project number 20 120, will be testing the usage of a nuclear reactor as a supplementary power generator at a diesel submarine. The vessel has been designed by the Rubin engineering company in 1989. Construction was started at the Krasnoe Sormovo shipyard in Nizhnii Novgorod, and then later continued at the Sevmash plant

Citation :

Russia completes new experimental "diesel-nuclear" submarine Dec 14, 2007 (BBC Monitoring via COMTEX) -- A new experimental submarine, built in secret, has been completed in Russia, Russia's corporate-owned military news agency Interfax-AVN website (in English) reported on 14 December from Severodvinsk. The Russian-language version of the report adds that the new sub "is designed to test unique technology in the form of a nuclear reactor installed aboard a diesel submarine as its auxiliary propulsion system". The B-90 Sarov diesel submarine was floated on 14 December, Sevmashpredpriyatiye spokesman Mikhail Starozhilov told Interfax-AVN. "The pilot diesel submarine is a multipurpose test vessel, which will be used to test newly developed and modernized types of arms and military equipment, the spokesman said. This submarine has a long life span and can be modernized many times over," AVN notes. In turn, the Russian navy's information and public relations service told AVN that the new sub is designed for tests of "combat and non-combat unmanned underwater vehicles, as well as other types of sea weapons and armament, and underwater equipment designed for various purposes, their prototypes, functional models (experimental systems), released from launchers" [grammar as published], the Russian-language version of the report adds. The plan is to carry out the submarine's factory running tests and state trials in 2008, the report notes. It goes on to say that the B-90 crew is 52 officers and warrant officers, formed by order of the Northern Fleet commander, its training completed. Capt 1st Rank Sergey Kroshkin is in command. "The construction of the new submarine proceeded amid heightened secrecy, as it - as experts consider - represents a unique experiment by Russian scientists and the military," the report sums up. The design of the submarine, from the Rubin firm, dates back to 1989, AVN recalls. It was laid down the same year at the Krasnoye Sormovo shipyard in Nizhniy Novgorod, its construction continued at Sevmash in Severodvinsk. "Open sources say that the project is number 20120. According to open-source data, the new submarine is very much like Project 877 Paltus diesel submarines but its under-water displacement is greater, at 3,950 tonnes rather than 3,050. "The experimental Project 20120 is designed to test unique technology in the form of a nuclear reactor installed aboard a diesel submarine as its auxiliary propulsion system," the report notes in conclusion. Sources: Interfax-AVN military news agency website, Moscow, in English 1050 gmt 14 Dec 07; and in Russian 1530 gmt 14 Dec 07