Work on deep modernization of air-missile system to intercept long-range based on the Tu-128 and gridlock with the design of the aircraft carrier for the new complex Tu-138, the OKB insistently demanded that the search for new creative ways in the development of long-range heavy fighter-interceptors. Almost simultaneously with the beginning of the design of long-range missile with variable sweep wing aircraft "145", the bureau started designing aviation complex long-range interception, based had to lie heavy fighter-interceptor with variable sweep wing, won the designation of aircraft design bureau "148"