Project 61M-class (Kashin)

The Project 61M, designated by NATO as the Modified Kashin class, is a series of guided-missile destroyers developed from the original Project 61 design approved in 1957. While the base class entered service in 1962, the Project 61M modification was introduced to enhance anti-ship and electronic warfare capabilities. The vessel Sderzhanny was the only unit completed to the 61M standard from its inception, while five additional Soviet vessels were modernized to the Project 61MP standard during the 1970s.

The design features gas turbine propulsion with engines situated in two distinct compartments. These units are removable via the funnels to facilitate servicing. The hull and superstructure were designed to be closed down against nuclear fallout, placing the operations room deep within the ship's interior. Project 61M and 61MP variants differ from the original configuration by the installation of SS-N-2 anti-ship missiles and AK-630 Gatling guns. The sensor suite was updated to include the MGK-335 Platina towed-array sonar and the Planshet-61 Combat Information Control System. These modifications also included a raised helipad to support Ka-25 series helicopters.

In Soviet service, these vessels were variously classified as guard ships, large anti-submarine ships, or large missile ships. Deployment spanned the Black Sea, Northern, Baltic, and Pacific Fleets. The Project 61MP vessel Smely was leased and later sold to the Polish Navy, where it served as ORP Warszawa until 2003. One modified vessel, Smetlivy, underwent a subsequent modernization designated Project 01090, receiving Kh-35 anti-ship missiles and updated sonar before being preserved as a museum ship in 2021. The Indian Navy operates a modified version known as the Rajput class, which features an aft helicopter hangar in place of the rear gun turret and SS-N-2 anti-ship missiles mounted adjacent to the bridge.