From 1976 this TU-144 was frequently used for test flights to test operation, payload and kerosene consumption over long distances, with the result that distances of over 6,000 kilometers were practicable. In 1977 she completed the first flights on the route between the Soviet capital Moscow and the provincial capital Khabarovsk in the Far East. The flights in both directions remained on average under three and a half hours for the 6,300-kilometer route.
