Modernizing Russian submarine forces is a priority for Vladimir Putin. The Russian president announced in 2025 the construction of nine submarines and another six by 2030. This week, the Russian Navy has begun testing the Khabarovsk, a vessel with the capacity to sink cities and unleash a nuclear tsunami thanks to the fact that it carries the Poseidon, its new underwater drone/torpedo.
The Khabarovsk is the new top-secret Russian submarine of Project 09851. It was launched in November 2025 and has now begun its tests in the open sea, according to Military Watch Magazine. The vessel entered the water on August 17, beginning its first voyage since construction began in 2014.
This first Khabarovsk-class ship is expected to join the Russian Pacific Fleet after completing tests. Afterwards, at least four submarines of this class could enter service, in parallel with the rapid expansion of the fleet of Borei-class ballistic missile submarines.
The Khabarovsk combines characteristics of the previous classes, Borei and Belgorod, according to H. I. Sutton, an expert in secret submarines and underwater warfare, in Naval News. Thus, the submersible integrates the stern section of the Borei and the bow section of the Belgorod. But the definitive thing is that, like the latter, the Khabarovsk has been specifically designed to carry the Poseidon nuclear submarine torpedo/drone.
Poseidon, more than a torpedo, an underwater drone
This gigantic intercontinental torpedo is the key. Russia is investing heavily in a new generation of "super weapons" designed to evade and potentially nullify conventional defenses, Sutton says. Among them, the Poseidon (2M39, NATO code name: Kanyon) stands out.
It is an autonomous submarine weapon, nuclear-powered and with nuclear weapons of effective intercontinental range. It is a strategic weapon designed to threaten coastal cities and strategic objectives. According to Moscow, it can also be used to attack tactical targets, including aircraft carrier battle groups.
The Poseidon's stated range is approximately 10,000 kilometers. This system was one of six strategic weapons publicly unveiled by President Putin in 2018, as part of Russia's effort to develop nuclear capabilities capable of bypassing emerging missile defense systems.
At the end of October 2025, Russia announced the tests of the Poseidon. According to Russian officials, the tests were carried out on October 28. They claim that this unmanned underwater vehicle is capable of carrying both conventional and nuclear payloads, and that nuclear propulsion gives it almost unlimited range.
The Poseidon is not exactly a torpedo, but rather a type of underwater drone. It is a nuclear-powered underwater vehicle that can carry a nuclear warhead. Specialized nuclear submarines are needed to transport it. Khabarovsk is the second that Russia has for this purpose (the first was Belgorod).
Khabarovsk, "a bearer of Poseidons"
Some characteristics of the new submarine are known and others are speculated based on the photographs published after its launch. The Khabarovsk is large: about 135 meters in estimated length and a beam of about 13.5. It is among the largest submarines in the world, but is somewhat shorter than those of the Borei and Belgorod classes. In the stern it is believed to be equipped with an OK-650V nuclear reactor, which gives it a high level of stealth thanks to its reduced acoustic signature, explains the Militarnyi publication.
The bow arrangement of the Khabarovsk, where the Poseidon tubes and conventional torpedo tubes are housed, is very similar to that of the Belgorod. The torpedoes are transported in two flooded hangars, one on each side. These are loaded and fired through large hatches in the bow, which give the appearance of giant torpedo tubes. Between them, another room houses the conventional heavy torpedoes.
The Khabarovsk is reminiscent of the Soviet cruise missile submarines of the Cold War (Papa and Charlie classes). Like these, it may feature a double-bubble pressure hull to maximize internal space despite the reduced space between the Poseidons, Sutton speculates.
