What You Need to Know: Russia’s fourth Project 636.3 - also known as the Kilo-class - Varshavyanka-class diesel-electric submarine, Ufa, is en route to join the Pacific Fleet, traveling via the Southern Sea Route and replenishing supplies in India.

-Launched in November 2022, Ufa is part of a series of six modified Kilo-class submarines contracted in 2016. Nicknamed “Black Holes” by the U.S. Navy for their stealth, these submarines are equipped with advanced acoustic, radar, and sonar systems.

-Capable of anti-ship and anti-submarine warfare, each boat is armed with Kalibr-PL cruise missiles and can travel 7,500 miles. The final submarine of the series is expected by late 2025.

Kilo-Class Submarines Headed Towards China: Russian Project 636.3 Submarine Heading to the Pacific

The Russian Navy's fourth modified Project 636.3 Varshavyanka-class diesel-electric submarine - or what many experts call the Kilo-Class -  will soon join the Pacific Fleet. The Ufa, which was built at the Admiralty Shipyards of the United Shipbuilding Corporation in St. Petersburg, is currently en route to the Pacific Ocean "by way of the Southern Sea Route," state media outlet Tass reported on Tuesday.

"The submarine, accompanied by the rescue tug Alatau, is making a call to the Indian port of Cochin in the Arabian Sea. During the port stay, the Russian vessels will replenish fuel, water and food supplies," the Russian news outlet added, citing a statement from the Russian Navy.

The fourth of six planned Project 636.3 Varshavyanka-class boats, Ufa was launched in November 2022 and completed its sea trials last year.

Kilo-Class: Six for the Pacific Fleet

The Kremlin signed a contract for building a series of Project 636.3 six diesel-electric submarines for the Pacific Fleet in September 2016. The lead submarine of the class, Petropavlovsk-Kamchatsky, was delivered to the Russian Navy on November 25, 2019, while the second Volkhov was subsequently handed over to the Fleet on October 24, 2020. A third submarine Magadan was delivered to the Russian Navy in November 2021, and joined the Pacific Fleet after transiting the Northern Sea Route in late 2022.

The fifth boat of the class Mozhaisk was launched last November and recently deployed in the Baltic Sea, and the sixth sub Yakutsk was launched on October 11, 2024. The final boat is on track to be delivered to the Russian Navy by the end of next year.

Russia's Infamous Black Holes

The modified Project 636.3 Varshavyanka-class submarines (NATO reporting name: Improved Kilo-II) have been referred to as the third generation of large diesel-electric underwater cruisers. The boats, which have been nicknamed "Black Holes" by the U.S. Navy, were designed to operate in shallower, coastal waters and are tasked with anti-ship and anti-submarine warfare.

The submarines are equipped with acoustic stealth and a target detection range, as well as the latest inertial navigator, advanced automated information and control system, more powerful high-speed torpedo, and improved missile armament. Each of the Project 636.3 submarines is 74 meters long while the boats displace more than 3,900 tons, and due to their strong hull, the submarines have an operational depth of 240 meters and can dive to a maximum depth of 300 meters.

With the engine plant placed away from the hull, which eliminates some noise, the diesel-electric submarines have been described as being among the world's quietest underwater cruisers, making them extremely dangerous. Each is also furnished with modern radar and communications systems and advanced sonars.

The boats can travel at speeds of up to twenty knots, while they have sea endurance of forty-five days and an operational range of up to 7,500 miles.

As reported by Brent Eastwood for The National Interest, these are true attack submarines in every sense of the word.

"Their purpose is to eliminate enemy subs and destroy surface ships. Their cruise missiles also give them land-attack capabilities. And since they are so quiet, they can also patrol close to shore and collect reconnaissance and intelligence data," wrote Eastwood. "The new Kilo subs are improved in other ways. They have enhanced internal navigation, a modern fire control system, and better torpedoes."

The Project 636.3 Varshavyanka-class boats are armed with Kalibr-PL cruise missiles that are launched from six 21-inch torpedo tubes while submerged.

Each Kilo-Class boat carries a crew of fifty-two submariners.

Author Experience and Expertise: Peter Suciu

Peter Suciu is a Michigan-based writer. He has contributed to more than four dozen magazines, newspapers, and websites with over 3,200 published pieces over a twenty-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a Contributing Writer for Forbes and Clearance Jobs. You can follow him on Twitter: @PeterSuciu. You can email the author: [email protected].

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