According to a photograph published on social media on Monday, August 17, 2026, the Project 09851 special-purpose nuclear-powered submarine BS-??? Khabarovsk, classified as an SSAN/SSDN (nuclear-powered auxiliary/drone-carrying submarine), departed Russia’s OAO PO Sevmash shipyard (Northern Machine-Building Production Association) in Severodvinsk the previous day for sea trials for the first time. The submarine is intended to carry 2M39 Poseidon combat unmanned underwater vehicles.
Photos: Massimo Frantarelli via X
According to available information, the submarine headed into the White Sea to conduct its first sea trials. In 2023, plans called for the vessel to enter service with the Pacific Fleet in 2026 as part of a new Submarine Division being formed in Kamchatka in 2024–2025. However, given that it is the lead ship of a new design, albeit one based on the Project 955 Borei nuclear-powered ballistic missile submarine, it appears likely to require around six months of acceptance trials. If these are completed successfully, the submarine is unlikely to be handed over to the customer before 2027.
Work on the submarine began on July 27, 2014, while its appearance was first publicly revealed during a televised presentation in November 2015. It was later disclosed that the vessel had been ordered in 2012, with delivery originally planned for 2020. The program was subsequently delayed by the COVID-19 pandemic, the war in Ukraine, and the need to introduce design modifications. The hull was launched on November 1, 2025, and has since undergone outfitting.
The primary role of BS-??? Khabarovsk will be to carry six autonomous nuclear-powered unmanned underwater vehicles/oversized torpedoes armed with thermonuclear warheads, designated 2M39 Poseidon, previously known as Status-6 and referred to by NATO as Kanyon. They are to be launched from dedicated 2P39 tubular launchers located in the bow. On October 21, 2025, the first test of a Poseidon prototype was reported.
Khabarovsk will join the 184-meter Project 09852 special-purpose nuclear-powered submarine BS-329 Belgorod, which entered service on July 8, 2022 and is also capable of carrying six Poseidons. Another submarine, BS-??? Orenburg, based on the modified Project 09853 design, is reportedly under construction, while two additional units have been ordered.
According to available information and analyses, the hull of the Project 09851 Khabarovsk has been shortened compared with the Project 955 Borei from 170 m to approximately 135 m, while submerged displacement has been reduced from 24,000 to around 10,000 tonnes. Beam remains unchanged at 13 m. Propulsion is reportedly provided by a single OK-650V pressurized-water reactor rated at 190 MW, giving the submarine an underwater speed of approximately 30–32 knots.
The most significant change is the absence of the missile compartment housing 16 launch tubes for R-30 Bulava/RSM-56 ballistic missiles, which accounts for the reduction in the vessel’s length and displacement. Based on materials released by the Russian Ministry of Defence, naval analyst and specialist H I Sutton of Covert Shores has produced a reconstruction of the submarine’s appearance, available HERE.
The submarine is intended for operations in the Arctic, with an operational diving depth of approximately 500 m. Its internal hull arrangement is reportedly designed to accommodate large robotic systems and unmanned underwater vehicles, including Poseidons. Endurance is estimated at 90–120 days, while the crew is expected to number around 100 officers and sailors.
In addition to the aforementioned Poseidon, Khabarovsk is also expected to carry a miniaturized nuclear-powered submarine mounted beneath the keel, in the same manner as Belgorod. The Russian Navy currently operates only a limited number of such vessels, including the two Project 1851.1 Paltus-class submarines AS-21 and AS-35, as well as Klavesin-2R-RM unmanned underwater vehicles. Khabarovsk is also expected to carry a DSRV-class rescue submersible on its upper hull and standard self-defense armament, such as conventional 533 mm or 650 mm torpedoes.
It appears that the Project 09851 Khabarovsk-class SSAN/SSDN (nuclear-powered auxiliary/drone-carrying submarine) set sail from Severodvinsk yesterday for the first time, heading for the White Sea to undergo sea trials.
+ The frigate “Admiral Gorshkov” in the background.
📸Later https://t.co/2O6mVWEVWe pic.twitter.com/qkEsFNtwCL— Massimo Frantarelli (@MrFrantarelli) August 17, 2026
See also:
- Russia christens Project 885M Yasen-M nuclear-powered submarine K-563 Ulyanovsk
- Russia: Strategic Submarine K-555 Knyaz Pozharsky Enters Service
- Russia Resumes Tests of the Nuclear-Powered 9M730 Burevestnik Missile
- Russia Carries Out Grom Strategic Nuclear Deterrence Drills
- Russia: Launch of the missile armament transport ship Akademik Makeyev
- Modernized Nuclear-Powered Missile Cruiser Admiral Nakhimov Begins Trials