The Project 670 Skat (NATO: Charlie I-class) SSGN was a Soviet nuclear-powered cruise missile submarine designed for anti-ship warfare, primarily targeting U.S. carrier battle groups. Entering service in the late 1960s, it was the first Soviet submarine to carry submarine-launched cruise missiles (SLCMs) in vertical launch tubes, significantly enhancing its strike capability.Armed with eight P-70 Ametist (SS-N-7 Starbright) cruise missiles, which could be launched while submerged, and a complement of 533mm torpedoes, the Charlie I was a formidable early attempt at a stealthy, rapid-response missile platform. However, its limited range, relatively noisy reactor, and outdated missile system led to its eventual replacement by the more advanced Charlie II and Oscar-class SSGNs.With a speed of 24 knots submerged and a diving depth of around 350 meters, the Charlie I was an important step in Soviet underwater strike doctrine but was phased out by the 1990s in favor of newer, more capable designs.