MOSCOW, July 26. /TASS/. The Russian Black Sea Fleet’s Project 636.3 Varshavyanka-class diesel-electric submarine Veliky Novgorod has arrived at the Sevastopol Shipyard for repairs, a source in Crimea’s defense circles told TASS on Friday.

"The Sevastopol shipbuilders will carry out planned dockside repairs of the Veliky Novgorod," the source said.

On July 18, the Sevastopol Shipyard (part of the Zvyozdochka Ship Repair Center within Russia’s United Shipbuilding Corporation) completed the dockside overhaul of the submarine Novorossiysk.

As reported earlier, the Black Sea Fleet’s other submarines of this project, the Rostov-on-Don and the Kolpino, will arrive at the Sevastopol Shipyard for dockside servicing after the Novorossiysk and the Veliky Novgorod.

Before April, the Veliky Novgorod and the Kolpino operated for a year and a half as part of Russia’s Mediterranean permanent taskforce. Their crews were rotated every three months. The subs entered the Mediterranean Sea after their inter-fleet passage from the Baltic Sea.

The Veliky Novgorod and the Kolpino are the fifth and the sixth submarines in the Project 636.3 series built at the Admiralty Shipyard (part of the United Shipbuilding Corporation) for the Black Sea Fleet. The submarines Rostov-on-Don, Veliky Novgorod and Kolpino numerously delivered cruise missile strikes against terrorist targets in Syria when they operated as part of the Russian Navy’s Mediterranean taskforce.

Project 636.3 submarines are referred to the third generation of diesel-electric subs. They develop a speed of up to 20 knots, can dive to a depth of about 300 meters and their sea endurance is 45 days. The sub has a crew of 52 men and displaces about 4,000 tonnes.

Varshavyanka-class subs are armed with Kalibr cruise missiles. Project 636 submarines are considered to be the most noiseless among Russian conventional subs. They have been dubbed the ‘Black Hole’ for their unique quietness. They are also furnished with modern radar and communications systems, sonars and 533mm torpedoes.