Columnist Andrei Kots drew attention to the vulnerability of Russian diesel-electric submarines (diesel-electric submarines) of Project 677 Lada, which are being built for the Russian Navy. The expert's opinion is cited by RIA Novosti.
Kots believes that such submarines are forced to periodically rise to the surface or under the snorkel to recharge the batteries. All this inevitably unmasks the boat and increases the risk of its detection by the enemy.
Initially, the designers laid down the possibility of equipping the Lada with an air-independent power plant, which would allow it to stay underwater much longer without surfacing, but so far these plans have not been implemented. It is this flaw that Kotz calls the only "Achilles heel" of the ship, noting that the rest of the submarines have high combat qualities.
Each such submarine carries six 533-mm torpedo tubes and is capable of using not only torpedoes and mines, but also Kalibr cruise missiles, which makes it a serious threat to surface and coastal targets. EADaily also reminds that the St. Petersburg Central Design Bureau Rubin is engaged in project 677. Submarines have replaced the legendary "Varshavyanka" and belong to the fourth generation of diesel-electric submarines.
The length of the hull is 66.8 meters, width — 7.1 meters, underwater displacement — about 2650 tons. The boat develops an underwater speed of up to 21 knots, dives to a depth of 300 meters and can autonomously stay at sea for up to 45 days. The crew consists of 36 people. The history of the project began in 1987, but the St. Petersburg submarine was laid down only in 1997 and joined the fleet in 2021. The first production submarine Kronstadt was handed over to the Navy in January 2024, Velikiye Luki in December 2025. In August 2026, the sixth ship of the series, the Maloyaroslavets, was laid down at the Admiralty Shipyards.