The new submarines are able to maintain such a low profile thanks to a clever implementation of a next-generation anti-reflective acoustic coating and a new improved hydro-acoustic system.
During the new submarines’ construction and design process, the development team managed to gather a lot of valuable data which, among other things, allowed them to significantly improve the Kilo-class submarines as well.
The Lada-class submarines are designed to defend coastlines against ships and other submarines, gather intelligence, provide surveillance and reconnaissance missions, and act as a mother ship for special forces. With its new air-independent propulsion plant, a Lada submarine can remain submerged for as many as 25 days.
Before 2020, the Russian Navy expects to receive 14 of the new 4th generation submarines.
Global Security describes the Project 677 Lada submarines.
Project 677 Lada submarines have high submerged cruising range and endurance, combat efficiency and reliability, and low acoustic signature. The sonar equipment includes highly sensitive direct-listening transducers at the forward end and a towed transducer array. It would be outfitted with six torpedo tubes, and its 18 weapons would comprise a mix of torpedoes and torpedo-tube launched missiles. Measuring 67 meters in length and 7.2 meters wide, it would include an anechoic tile coating on the outer hull and a skewed 7-blade propeller. The vessel's surface speed would be 10 kt; submerged 21 kt. The submerged cruising range using economic speed is 500 nautical miles at 3 kt. The maximum diving depth is 250 m, with an endurance of 45 days with a crew of 34.
- acoustic field of the submarine has been considerably reduced (in comparison with submarines of previous generations - several times);
- radio-electronic equipment of a new generation has been installed with a state-of-the-art element base;
- an integrated system has been installed for automatic control of submarine and its combat and technical facilities;
- an inertial navigation complex has been installed which provides safety of navigation and determination of motion parameters with specified missile armament accuracy during long underwater operation;
- a variable-speed propulsion plant of a new design has been fitted;
- a storage battery with increased service life has been installed.
Russia has been negotiating with China about Lada Submarines for a couple of years.