Project 21631 Buyan-M is a Russian river-sea guided-missile corvette class designed by Zelenodolsk Design Bureau and built at Zelenodolsk Plant named after A.M. Gorky. The class combines shallow-draft inland-water mobility with an 8-cell UKSK launcher for Kalibr or Oniks missiles, a 100 mm gun, and close-in air defense.
Buyan-M corvettes are built around a compact UKSK launcher that carries Kalibr-family cruise missiles.
| Launched item | Item type | Launch evidence |
|---|---|---|
 | Sea-launched cruise missile family | Naval News describes Project 21631 corvettes as carrying 2x4 UKSK cells for Kalibr or Oniks missiles, making the class a shipborne launch platform for Kalibr strikes. Sources: Buyan-M-class Corvette ‘Graivoron’ Commissioned with Russia's Black Sea Fleet - Naval News |
Russian military intervention in the Syrian Civil War: Three Buyan-M corvettes, Grad Sviyazhsk, Uglich, and Veliki Ustyug, were part of the Caspian Flotilla group that fired Kalibr missiles at targets in Syria in October 2015. Russia-Ukraine war: Buyan-M-class ships are repeatedly identified in public reporting as Kalibr-capable Russian missile corvettes relevant to the Black Sea/Azov naval war; a 2025 Ukrainian strike claim against a Buyan-M in the Sea of Azov was reported but not independently verified in the cited article.
Russian military intervention in the Syrian Civil War: Three Buyan-M corvettes, Grad Sviyazhsk, Uglich, and Veliki Ustyug, were part of the Caspian Flotilla group that fired Kalibr missiles at targets in Syria in October 2015. Russia-Ukraine war: Buyan-M-class ships are repeatedly identified in public reporting as Kalibr-capable Russian missile corvettes relevant to the Black Sea/Azov naval war; a 2025 Ukrainian strike claim against a Buyan-M in the Sea of Azov was reported but not independently verified in the cited article.
Timeline
The Washington Institute reported that three Buyan-M corvettes - Grad Sviyazhsk, Uglich, and Veliki Ustyug - were part of the Caspian Flotilla group that fired Kalibr missiles at targets in Syria.
Sources: Russia's Cruise Missiles Raise the Stakes in the Caspian
Graivoron entered the Russian Navy's Black Sea Fleet, showing the class remained an active Kalibr-bearing platform after the Syrian campaign.
Sources: Buyan-M-class Corvette ‘Graivoron’ Commissioned with Russia's Black Sea Fleet - Naval News
Zelenodolsk Shipyard launched Stavropol, the final Buyan-M hull on order for the Russian Navy.
Sources: Russia launches Final Buyan-M-class Corvette Fitted with Kalibr cruise missiles
