Russia Launches Giant Special-Missions Submarine

Belgorod's launch (Russian state media)

By The Maritime Executive 04-26-2019 12:50:02

Russia's Sevmash Shipyard has finally launched the Belgorod, the world's longest submarine. She was laid down as an Oscar II-class vessel in 1992, but construction proceeded in fits and starts as Russia went through multiple economic and political transformations, and her launch ceremony was delayed for decades. 

Belgorod's mission has changed with the times. The Oscar II class was built to carry the heavy P-700 Granit anti-ship cruise missile, and the design has an unusually wide and spacious hull form to accommodate twin batteries of this weapon. But over the past seven years, Belgorod has been lengthened by 100 feet and repurposed for different tasks.

First, she is designed to support special covert missions like installing seafloor sensors. She is believed to have the capability to support the top secret, deep-diving Losharik, a manned mini-sub that can access subsea cables and other seafloor infrastructure down to 1,000 meters.

Second, unlike other Oscar IIs, Belgorod has a large bulge at her stern with several hatches, and her starboard-side rudder skeg appears to have arrangements for towing. The alterations lead some analysts to suggest that she may be equipped with a spool and deployment system for covert cable-laying.

Third, she is also the submarine deployment platform for the Poseidon, a long-range drone torpedo for delivering strategic nuclear warheads to littoral targets like seaports. Western analyts believe that the Belgorod will be able to carry four to six of the 80-foot-long Poseidons, which have a range of about 6,000 miles, a top speed of about 55 knots and an estimated nuclear payload capacity of 10 to 100 megatons. (By comparison, Russia's superheavy Sarmat ICBM can carry warheads totaling up to eight megatons.) An underwater bomb detonation of this size would create a large tsunami, flooding inland areas and spreading radioactive fallout over a wide radius.