Submarines of projects 705, 705K "Lira" (according to NATO classification - "Alfa") - a series of Soviet nuclear submarines. Small high-speed single-shaft boats with a titanium hull had no analogues in speed and maneuverability and were designed to destroy enemy submarines. Difficulties in maintaining these submarines and a reduction in funding due to the beginning of Perestroika led to the end of the career of these ships. The project was developed in SKB-143. The idea of ​ ​ the project was proposed by the head of the prospective planning sector A. B. Petrov. Chief Designer M.G. Rusanov, since 1977 - V.V. Romin.