The head submarine of project 677 "Saint-Petersburg" were sent on upgrading

The Head diesel-electric submarine of project 677 (code "Lada") "Saint-Petersburg" went for routine maintenance and upgrades. This reports the press service of the defense Ministry.
According to information, the SSK "St. Petersburg", which is in trial operation in the Northern fleet, left the base on the Kola Peninsula and headed to Kronstadt, where will be on modernization and maintenance. The defense Ministry stressed that the entire submarine inter-fleet transfer from the Barents sea to the Baltic will hold on the surface. On its exit was accompanied by the rescue tug ship "Pamir".

The report did not specify the timing of the works on the submarine, as well as what will be the upgrade.
Head boat "St. Petersburg" series of non-nuclear ships of project 677 was laid on the stocks "Admiralty shipyards" in December 1997, launched October 28, 2004. In April 2010, the boat was accepted into the Russian Navy in trial operation, which continues until now.
Diesel-electric submarines of project 677 refers to the fourth generation of NNS. It is designed to combat submarines and surface ships of the enemy, destruction of its coastal sites, minefields, transport units and cargo of special forces.
The Displacement of the submarine is 1765 tons, length — 67 m, width — 7 meters, submerged speed — 21 knots, diving depth — 300 m, autonomy — 45 days. The submarine is equipped with six torpedo tubes caliber 533 mm.