Buyan-M (Project 21631 (Sviyazhsk))

The Buyan-M class (Project 21631) is a series of small multi-purpose missile corvettes designed for operations in coastal zones and inland waterways. These vessels are notably equipped with the Kalibr cruise missile system, providing significant strike capabilities despite their compact size.

Developed by the Zelenodolsk Design Bureau as an evolution of the Project 21630 gunboats, the Project 21631 class was designed to bypass international treaty limitations by placing strategic strike capabilities on small, shallow-draft river-sea vessels. The lead ship of the class, Grad Sviyazhsk, officially entered service with the Russian Navy's Caspian Flotilla in 2014. The class gained global attention in October 2015 when Caspian Flotilla units launched long-range land-attack missiles against targets in Syria, and they have since been actively deployed in the Black Sea during the conflict in Ukraine. Today, over ten Buyan-M vessels are active across Russia's Baltic, Black Sea, and Caspian fleets, cementing their legacy as highly cost-effective platforms for regional power projection.