OVERVIEW: The PL-677 Lada [B 585 Sankt Peterburg] is a diesel-electric attack submarine (SSK) operated by the Russian Navy. It represents the fourth generation of Russian diesel-electric submarine design, intended to provide a quieter and more capable platform than its predecessors. The Sankt Peterburg is the lead unit of the Lada class (Project 677).

DETAILS:
The Project 677 Lada-class was conceived as a successor to the Kilo-class submarines, aiming to improve stealth, endurance, and combat capabilities. Development was protracted, with the lead boat, Sankt Peterburg, laid down in 1997 but not commissioned until 2010 after a lengthy and troubled trials period. The design emphasizes modularity and the incorporation of advanced technologies, including improved sound dampening, an automated combat management system, and potentially, an air-independent propulsion (AIP) system for extended submerged endurance, although the initial boats were not equipped with AIP. The Lada class was intended to be a mainstay of the Russian Navy's non-nuclear submarine force, although construction has been slow due to funding constraints and technical challenges.

The PL-677 Lada is designed to conduct anti-submarine warfare (ASW), anti-surface warfare (ASuW), and intelligence, surveillance, and reconnaissance (ISR) missions. Its quiet operation makes it particularly well-suited for operations in littoral waters and for covert surveillance. The submarine is capable of engaging surface combatants and submarines with torpedoes, while the availability of the SA-N-10 Gimlet (9K310 Igla-1) mast launcher provides a limited self-defense capability against aerial threats. The Signal Ejector is likely used for communication and decoy purposes.

The submarine's sensor suite is comprehensive and designed for effective detection and tracking of targets in a challenging underwater environment. The installation of the Quad Loop DF and Acoustic Intercept (MG-53) provide direction finding capabilities and allow for the detection and analysis of enemy electronic and acoustic emissions. The Squid Head [MRP-25] surface search radar allows for surface contact detection and navigation. The Mouse Roar [MG-519 Arfa] sonar system provides active and passive detection capabilities, complemented by the hull-mounted Lira sonar. The Snoop Tray 2 [MRK-50 Kaskad] likely serves as an integrated navigation and combat management system interface. The inclusion of both optical and LLTV periscopes improves situational awareness and target identification in varying visibility conditions. The towed array Lira significantly enhances the submarine's passive sonar detection range, particularly against quieter targets at longer distances.

SPECIFICATION: Length: 66.8 m || Beam: 7.1 m || Draft: 6.7 m || Disp: 1765 t

SENSORS: Quad Loop DF || Squid Head [MRP-25] || Mouse Roar [MG-519 Arfa] || Snoop Tray 2 [MRK-50 Kaskad] || Acoustic Intercept [MG-53] || Lira [Hull] || Lira [Towed Array] || Generic Submarine Periscope, Optical || Generic Submarine Periscope, LLTV

ARMAMENT: 533mm TT || SA-N-10 Gimlet [9K310 Igla-1] Mast Launcher || Signal Ejector