The Russian Navy's Project 677 (Lada) is a submarine class designed by the Russian Rubin Design Bureau. The class is sometimes referred to as the Saint Petersburg (or Sankt Peterburg) class, after their lead ship. A program to develop a "fourth generation" diesel-electric submarine, it produced a highly improved version of the Project 636 Kilo class with much quieter, new combat systems, and air-independent propulsion.
St. Petersburg began initial sea trials on 29 November 2005.
The Lada-class diesel submarine launched in October 2004 is the best in the class featuring virtual silence, powerful missiles and torpedoes, and sophisticated sonar equipment. The Admiralty Shipyard is building another three Lada-class submarines, and plans to launch between four and six of them by 2015.
Several less capable variants — like the Project 1650 class (named for the Amur river) — have been designed for export.