Russia tests new submarine designed for ultra long-range nuclear torpedo

Russia’s Northern Machine-Building Enterprise sent the nuclear-powered submarine Khabarovsk to sea for factory trials on August 17, the vessel’s first time underway since construction began in 2014, according to Russian defense-monitoring channels.

The submarine, built under Project 09851 at the Sevmash shipyard in Severodvinsk, is designed to carry the Poseidon (NATO name: KANYON) nuclear-powered underwater drone system. Russia’s Rubin Central Design Bureau for Marine Engineering designed the vessel under a contract signed with the Russian Ministry of Defense on June 19, 2012. Construction formally began July 27, 2014.

Khabarovsk was floated out of its construction hall on November 1, 2025, ahead of Monday’s sea trials. The submarine’s contract had originally called for delivery to the Russian Navy in 2020, though reports have not disclosed the reason for the six-year delay.

The vessel is believed to carry six 2P39 launch tubes for the 2M39 Poseidon underwater vehicles. Russian media have described each Poseidon as roughly 66 feet (20 meters) long, about six feet (1.8 meters) in diameter and weighing around 110 tons. Analysts have assessed its range at approximately 6,200 miles (10,000 kilometers), though claims of a 100-knot top speed have not been independently confirmed.

President Vladimir Putin said Russia conducted its first test involving an activated nuclear power unit on the Poseidon on October 28, 2025, launching the weapon from a submarine.

“For the first time, we managed not only to launch it with a launch engine from a carrier submarine, but also to launch the nuclear power unit on which this device passed a certain amount of time,” Putin said.

“There is nothing like this,” Putin said of the weapon, one of six strategic systems he first revealed publicly in 2018.

That October test has not been independently verified. Some Western observers noted the presence of six unidentified vessels off Novaya Zemlya in the Kara Sea on the day Putin said the test occurred, though no confirming movement of Russian support ships or NATO surveillance assets was widely reported at the time.

Photographs of Khabarovsk’s float-out show a stern section, propulsion system and rudders nearly identical to those on Russia’s modified Borei-A class ballistic missile submarines, according to Russian defense channels.

Illustration by The Defence Blog

Khabarovsk will join Russia’s Pacific Fleet once trials conclude. Russia previously delivered its first Poseidon carrier, the submarine Belgorod, to the Navy on July 8, 2022. Belgorod, built under Project 09852, was converted from an unfinished Project 949A cruise missile submarine and carries four 2P39 launch tubes rather than six. Russia has said it plans to field a total of five Poseidon-armed submarines.

Rubin’s design bureau reported plans in 2016 to begin design work on a follow-on vessel, Project 09853, believed to be a modified or serial version of the Khabarovsk design. No public reporting has confirmed that construction of a Project 09853 submarine has begun.

Russia is building a dedicated submarine base for the Project 09851 and 09852 vessels, along with their Project 20183 support ship, at Kraсheninnikov Bay on the Kamchatka Peninsula.