In 1987, Sukhoi started converting the first prototype (designated ) from a T-10S airframe at its experimental plant in Moscow. Although it had canards, the first prototype, like several subsequent aircraft, lacked the many physical alterations of the new design. It made its first flight after conversion on 28 June 1988, piloted by Oleg Tsoi, followed by the second prototype in January 1989. Following the conversions of the two Su-27M prototypes, the actual production of the aircraft was transferred to the country's Far East where it was carried out by KnAAPO. The third aircraft (), which was the first new-built Su-27M and first to be constructed by KnAAPO, made its first flight in April 1992. By then, the Soviet Union had disintegrated, and the ensuing economic crisis in Russia throughout the 1990s meant that the original plan to mass-produce the aircraft between 1996 and 2005 was abandoned, with the aircraft to serve as experimental test-beds to validate the canards, the flight-control system and thrust-vectoring technology. In total, two prototypes, nine flying pre-production and three production aircraft were constructed by 1995; the production aircraft were delivered in 1996 to the Russian Air Force for weapons testing.